On a vibrant earth, plants are found everywhere. Whether it is an endless plain, a hot desert, a deep and lightless seabed, or an unusually cold polar region, there are traces of plants everywhere. So, what exactly is a plant? Who are the members of the plant family? How are they classified? What are the basic structures of plants? What is the growth process of plants? How can plants protect themselves in times of danger? ...... Plants, like humans and animals, have their own rules of life and unique lifestyles. Now, let's visit the huge plant family and learn about the infinite mysteries of plants!
▋First acquaintance with plants - the natural "coat" of the earth
In life, plants can be seen everywhere at any time: willow branches in spring, flowers bloom in summer, fruits in autumn, cold plums and snow in winter... Plants are spread all over the surface of the earth, as if the natural "coat" of the earth, bringing vitality to nature. Now, let's get closer to the plants and reveal what they really are.
The name of the plant
In order to facilitate distinction and memory, people gave each plant a scientific name. In addition to their scientific names, many plants have their own common names. The common name of the plant is generally interesting, some are related to their shape, such as bluebell, because its flower type is like a bell; some are related to the use, such as stretching grass, because it has the effect of stretching muscles and activating blood.
The number of plants
We currently know more than 500,000 species of plants, including algae, bryophytes, ferns, gymnosperms and angiosperms. They vary in size, form, and lifestyle, and together form a complex plant kingdom.
Composition of plants
A higher plant usually consists of roots, stems, leaves, flowers, fruits, and seeds. They each have different functions, such as: roots, stems, leaves are responsible for transporting water, inorganic salts and nutrients, are the vegetative organs of plants; flowers, fruits, and seeds are mainly responsible for inheritance and are reproductive organs. Each part of the plant performs its own duties and works in coordination to ensure the survival and reproduction of the plant.
Uses of plants
Only plants and a very small number of bacteria on Earth can make their own nutrients, and they are the basis for feeding all life on Earth, known as producers. Plants not only provide humans with the oxygen, food and energy necessary for survival, but also provide human beings with cotton, linen, rubber and many other raw materials for production.
Without plants, all life on Earth would cease to exist.
The most primitive plant
Algae are the oldest and most primitive group of plants on Earth. They appeared billions of years ago, and after a long time, until hundreds of millions of years ago, they were still the only green plants on Earth. Today, algae plants are not the hegemons of the plant kingdom, but they are still thriving and spread all over the world.
Ferns are on the rise
More than 400 million years ago, some green algae evolved into the primitive vascular plant, the naked fern. However , they became extinct at the end of the Devonian period , replaced by a variety of ferns that evolved from them. From the Carboniferous period onwards, ferns became the protagonists of terrestrial vegetation at that time. Many tall tree-like ferns flourish, such as scaled wood, reed wood, seal wood and so on.
Gymnosperms are prevalent
More than 200 million years ago, terrestrial vegetation was replaced by gymnosperms. The most primitive gymnosperms also evolved from gymnosperms. The Mesozoic Era was the period when gymnosperms flourished, so the Mesozoic Era is also known as the Gymnosperm Age.
gymnosperm
Angiosperm era
About 65 million years ago, angiosperms developed rapidly, replacing the dominant position of gymnosperms. Angiosperms are green flowering plants. Until now, angiosperms have remained the most diverse, widely distributed, and most adaptable dominant taxon on Earth. At present, there are more than 200,000 species of angiosperms known to mankind. Most of the food, vegetables, oil crops and fruit trees we grow are angiosperms.
▋ Classification of plants - "orderly growth and youth"
From the oldest algae plants, to tenacious ferns, to angiosperms all over the world, the plant family can be said to have undergone billions of years of development, and the "family power" has grown day by day. This huge family is like our human family, old and young, and the members are very close to each other.
Schematic diagram of the plant family
Basic taxonomy of plants
There are so many plants on Earth that they make up a huge family of plants. In order to better understand these plants, botanists have developed taxonomic methods for phylums, orders, families, genera, and species. At present, the plant kingdom can be mainly divided into five phylums: algae, bryophytes, ferns, gymnosperms and angiosperms.
Phylum Algae
Algae are the oldest plants on Earth, with more than 30,000 species. They have a simple structure, no differentiation of roots, stems, and leaves, but contain chlorophyll, which can make the required nutrients through photosynthesis. Algae plants mainly live in water, and some live on land, which can be divided into cryptoalgae phylum, dinoflagellate phylum, golden algae phylum, xanthellae phylum, diatomaceous phylum, brown algae phylum, red algae phylum, naked algae phylum, green algae phylum and rotifer phylum and other categories.
Bryophyta
There are about 23,000 species of bryophytes, with no real roots, and are often densely packed together, furry, like a green blanket. Most bryophytes grow in shady and wet environments, such as forest soil surfaces, tree branches, swampy areas, water streams and shady corners, mainly including mosses and mosses.
Fern phylum
Ferns are a lower class of vascular plants, with no flowers and leaves growing from underground stems and slowly unfolding as they grow. Ferns mostly grow in wet places, about 12,000 species, mainly divided into four classes: naked ferns, stone pines, arthropods, and true ferns. Among them, the naked fern sporophytes have no differentiation of roots, stems and leaves.
Ferns are tenacious
Gymnosperm phylum
Gymnosperms get their name from the fact that their seeds are mostly exposed to the outside, they are perennial woody plants, mostly tall trees with uniaxial branches, a few are shrubs, and vines are the rarest. Gymnosperms generally grow tall, with about 800 species, mainly divided into five classes: Mai Ma Teng, Yew, Cycads, Ginkgo biloba and Conifer.
Angiosperm phylum
Angiosperms are also called flowering plants, which have flowers in addition to roots, stems, and leaves. Flowers are important organs that distinguish them from other plants and reproduce offspring. Angiosperms are the largest and most advanced phylum in the plant kingdom, and are divided into dicotyledons and monocotyledonous plants according to their seed structure. Dicotyledonous plants have two embryonic leaves, while monocotyledonous plants have one embryonic neutron leaf.
Lower and higher plants
Currently, plants in nature are at different levels of evolution. In general, the earlier the taxa appears, the lower the evolutionary level; the later the taxa appears, the higher the evolutionary level. Plants are thus divided into lower and higher plants. Lower plants do not have roots, stems, and leaves to differentiate, the vast majority of reproductive organs are single-cell structures, and zygotes formed after fertilization do not develop into embryos. Only algae in the plant kingdom belong to the lower plants. Higher plants generally have the differentiation of roots, stems and leaves, reproductive organs are mostly cellular structures, and fertilized eggs develop into embryos, including bryophytes, ferns, gymnosperms and angiosperms. Among them, bryophytes are the lowest-level higher plants, and angiosperms are the most evolved taxa among higher plants.
▋ The form and life cycle of plants - life is so diverse
When it comes to plants, not only are they diverse, but each plant itself has a different form and life cycle. Some plants are tall and straight, some plants are short and clustered, some can live for hundreds of years or even thousands of years, and some have only a few weeks in their lives.
herbaceous plant
The stems of herbaceous plants are soft, juicy and elastic, and are rarely broken when blown down by the wind, which we call herbaceous stems or grassy stems. Plants with this stem are called herbaceous plants, such as various wild grasses commonly found along the roadside, various crops and vegetables planted in the field, and so on.
Life cycle of herbs
There is a class of herbaceous plants from seed germination, growth, flowering, fruiting to wilting and death, generally only 1 to 2 years, they are called annual or biennial herbs, such as roadside weeds, morning glory in the courtyard and so on. There is also a class of herbaceous plants from seed germination to grow and flower, fruit, life can last for many years, called perennial herbs, such as bright red dazzling fire crane flowers, beautiful and delicate tulips, flowers blooming in all seasons begonias, evergreen evergreens and so on.
Wood plants
We call plants with strong stems and lignification insides woody plants. Some woody plants have many branches growing not far from the ground, so that the main trunk and branches are not clear, and they grow relatively short, as if they are bushes, which we call shrubs, such as rhododendrons, hibiscuses, etc. And like kapok, sycamore, etc., there is a clear trunk, and the trunk is branched at a fairly high place from the ground, usually the plant is also relatively tall, this kind of woody plant we call it a tree.
Apples are woody plants whose fruits are delicious and delicious
Life cycle of woody plants
Woody plants are mostly perennials, and their stem cells become hard due to lignification, and they grow and widen year by year. Their lifespan is usually several decades, or even thousands of years. During their life cycle, neither the above-ground nor the underground part will all die.
Fujiki Plant
Vine plants, also known as vine plants, their stems or branches are easy to elongate and can not stand upright, must rely on tendrils or vine stems wrapped, clinging to other objects or even creeping on the ground to grow normally. The stems of vines are also divided into herbaceous and woody, the herbaceous is called herbaceous vine, such as morning glory, and the woody is called woody vine, such as wisteria.
Annual plants
Plants that complete the whole process of life in a year are annual plants. Their life cycle begins with seed germination, followed by the formation of seedlings, after growth and development, flowering, powder, and then produce fruits, seeds, and finally plants wither and die.
Life cycle of soybeans
Biennial
Some plants, which sprout and grow in the first year, do not flower, and after the hibernation period, they grow, flower, and bear fruit again in the spring of the following year. A life cycle like this spans two years, and plants that bloom in the second year and die after fruiting are biennials. Mullein, burdock and thistle are common biennials.
Perennials
Perennials are plants that have a growth period of more than two years, including perennial herbaceous plants and woody plants. They germinate from seed germination to seedling growth, and then after several years of growth, they can mature and blossom. Since then, they have to go through the growth stage of flowering and fruiting every year. Common trees and shrubs are perennials.
▋ The root of the plant - nutrient transporter
Just as our human growth requires nutrients from various foods, the growth of animals and plants cannot be without nutrients. For plants, many of their nutrients come from the soil, so the roots of plants become the most important "nutrient transporters" in the growth of plants.
The internal structure of the root
The external morphology of the root
From the external morphology, there are two types of roots: straight roots and whisker roots. Straight roots generally have thick taproots, and there are some relatively small side roots around the main roots, such as the roots of pine trees; the roots of the whiskers have no main roots and side roots, and are composed of many roots of similar size, which are like unkempt whiskers, such as the roots of wheat.
Whisker root morphology
Root tip
The root of the plant goes from the tip to the section of the root hair, called the root tip. The root tip is the area where root life activity is most active. The root tip is generally composed of four parts: the root crown, the meristem area, the elongation area, and the root hair area. The thin fur near the root tip is called the root hair; the cap-like structure of the outer layer of the root tip is called the root crown; and the meristem inside the root crown is called the growth point.
In terms of internal structure, the roots are composed of the epidermis, the cortex and the column. On the periphery of the root is a very thin layer of cells called the epidermis. The epidermis has a root hair on the outside. There are many parenchymal cells in the epidermis, called the cortex, and the innermost layer of cells in the cortex is called the endothelium. The inner edge of the endothelium is the central part of the root, called the column.
Taproot
When the seed germinates, it first breaks through the seed coat and grows outward, and the part that grows vertically downward is the taproot. For example, the fava bean we are familiar with, when it sprouts, breaks through the seed coat and protrudes outward into a white strip of roots, and then continues to grow downward to form the main root.
Lateral roots
After the primary root grows to a certain length, it produces a number of branches, which are collectively referred to as lateral roots. In the growth process of soybean sprouts and mung bean sprouts, we sometimes see that when the primary root grows longer, it will grow some branches to the side at the inlet end of the main root, and these branches are the side roots. Lateral roots may branch again during growth, forming new lateral roots.
Primary and lateral roots
Fixed and indefinite roots
The root that develops from the radicle and has a certain fixed position is called the fixed root. The root consists of both the primary root and the lateral root. The roots that grow from the stems or leaves of plants during their growth are called adventitious roots. For example, a weeping willow branch is cut and inserted in the wet soil, and soon some roots will grow on the willow branch inserted into the mud, which is the indefinite root.
The function of the root
Roots are the vegetative organs of plants, mostly growing in the soil, forming the underground part of the plant. The roots of plants are responsible for fixing the plant body, absorbing water and inorganic salts, transporting and storing nutrients. For example, the pillar roots of corn have the effect of strengthening plant resistance to external forces and consolidating the erection of plants; and the roots of sweet potatoes, radishes, etc. that we eat have the function of storing nutrients.
Metamorphic roots
Some plants are metamorphosed by their roots due to environmental influences or special needs. At this time, not only their appearance and structure are different from the roots of ordinary plants, but even their role is different from that of ordinary roots. We call the roots of these plants metamorphosis roots. Metamorphic roots are mainly made up of pillar roots, parasitic roots, climbing roots and qi roots.
Pillar root
▋ The stem of the plant - a different "bone"
The reason why humans are able to stand, walk and perform various activities is mainly supported by bones. Without bones, people would collapse on the ground like a pool of mud. Similarly, the plant can be displayed in a colorful form, and the credit of its "skeleton", the stem, cannot be ignored.
The shape of the stem
The shapes of the stems are diverse, ranging from thick to thin, long and short, with great variations. The stems of most plants are cylindrical, but there are also some plants whose stems take on other shapes. For example, the stems of mint and perilla are square; the stems of thorn triangular and fragrant are triangular; the stems of motherwort and patchouli are quadrangular; the stems of cactus and crab claw orchid are flattened.
The external structure of the stem
The stem is the backbone of the aerial part of the vascular plant, the lower part is connected to the root, and the upper part generally produces leaves, flowers and fruits. The part of the stem where the leaves grow, called the node. The part between the two nodes that does not have long leaves is called the internode. Stems with leaves and buds are called branches. The marks left after the leaves on the branches are shed are called leaf marks.
Schematic diagram of the external structure of the stem
The internal structure of the stem
The internal structure of the stem varies with the degree of development and the plant species. In addition to the growth point at the top of the stem of woody plants, there is also a formation layer on the inside of the epidermis, which can constantly produce new cells. The growth point of the stem is mainly to make the stem grow tall, and the formation layer can constantly produce new cells. The growth point of the stem is mainly to make the stem grow tall, and the formation layer produces new cells outward and internally, making the stem thicker and stronger. Most herbaceous plants have only xylem and phloem in their stems, but no layers, so the stems grow to a certain extent and are no longer thickened.
Schematic diagram of the internal structure of the stem
Cylindrical stem
Categories of stems
In the colorful natural world, due to the influence of the environment, water, soil, sunlight and many other conditions, the stems of plants vary widely and in different forms. In general, there are four types of plant stems, namely upright stems, winding stems, climbing stems, and creeping stems. Among them, the upright stems of trees and the winding stems of morning glory are the most familiar to us.
The stems of cucumbers belong to the climbing stems
Herbaceous stems and woody stems
The stems of plants can be divided into two categories according to texture: herbaceous and woody. Herbaceous stems are short and soft; woody stems are relatively hard and distinguished from trees and shrubs. The stem trunk of the tree is obvious and grows very tall; the stem trunk of the shrub is not obvious, and the growth is relatively short.
Low shrubs
Metamorphic stems
In the process of long-term adaptation to the environment, the stems of many plants change their morphology and structure due to changes in their function, and eventually form metamorphosed stems. Metamorphic stems are divided into two categories: aboveground metamorphic stems and underground metamorphic stems. Aboveground metamorphic stems include stem spines, tendrils, etc.; underground metamorphic stems are shaped like roots, such as potato tubers, onion bulbs, etc.
A wide variety of underground stems
The role of the stem
Each mature higher plant has a stem, and the stem is the backbone of the plant body. It supports the branches and leaves so that they are fully stretched; it supports the flowers until they wither. The stem is also the transport organ of the plant body, through which the rest of the plant body can get the nutrients needed for growth.
The stems grow leaves, flower, bear fruit, and support them
Lotus root: The lotus root is the underground stem of the lotus, its nodes are particularly thin, with leaves and whisker roots on it, and the internodes are fat and edible. Due to the lack of air in the underwater silt, there are many small holes in the body of the lotus, and with these small holes, the lotus can send the air absorbed by the leaves to the various parts of the stem.
▋ Plant leaves - "green factory"
When it comes to green, I believe that the first thing that comes to mind is plants. The green of the plants not only makes nature full of vitality, but also becomes synonymous with our goal of healthy life. So, where does this "green" come from? This starts with the "green factory" of the plant, the leaves.
Composition of leaves
The shape of the leaves
The leaves of the plant come in many shapes, including heart-shaped, fan-shaped, and arrow-shaped. Ginkgo biloba leaves are like a little fan; maple leaves are like our palms; morning glory leaves are like green hearts; pine leaves are like embroidery needles; willow leaves are slender and long, like eyebrows.
The color of the leaves
The leaves of most plants are green because the leaves of plants contain more chlorophyll. However, there are some plant exceptions, such as begonia leaves are red, this is because the leaves of these plants contain more anthocyanins, and if the content of anthocyanins exceeds the content of chlorophyll, the leaves appear red.
The color of the leaves is determined by the amount of pigment in the leaves
Although the leaves of plants are very different, a complete leaf is usually composed of three parts: leaf, petiole and leaf. The leaves are the main part of the leaves and are the main places where plants perform photosynthesis and transpiration. The petiole is the part that connects the leaves and stems, in which catheters and sieve tubes communicate with the stems and leaves to transport water and nutrients. The leaves are small leaves that grow at the base of the petiole and at the junction of the stem, and their main role is to protect young shoots.
The internal structure of the leaves
The leaves are divided into three parts: epidermis, mesophyllum and veins. The epidermis is divided into the upper epidermis and the epidermis, and between the upper and inferior epidermis is the mesophyll, and the mesophyll cells contain a large number of chloroplasts. Chloroplasts are the "in-house factories" where plants photosynthesize and make nutrients. There are many veins distributed between the leaf flesh, and the leaf veins have catheters and sieves to transport water and organic nutrients.
Single and compound leaves
Depending on the number of leaves on the petiole, the leaves can be divided into single and compound leaves. A single leaf that grows only one leaf on a petiole is a single leaf, such as the leaves of apples, pumpkins, and corn; the leaves of two or more completely independent small leaves on a petiole are compound leaves, such as the leaves of fallen peanuts, clover, acacia and aster.
The leaves of the fallen peanuts are typical compound leaves
Leaf order
The leaves on the stem of a plant are not only fixed in a few pieces, nor do they grow in a disorderly manner. They can grow new leaves indefinitely, but the order in which the leaves grow on the stem is called the leaf order. The leaf order can be roughly divided into three types: alternate, paraphyletic and rotational.
A poinsettia
Metamorphosed leaves
In order to adapt to different environments and perform special functions, the leaves of some plants have mutated in form and structure, and the leaves of such plants are called metamorphic leaves. The bracts of Asteraceae, the scales of lilies, etc. are all metamorphosed leaves. Among them, the catcher leaf that can prey on small insects is a very special metamorphic leaf.
Water holes: There are some small holes called water holes at the edges of the leaves, which can directly drain excess water from the plant. Water pores do not have guard cells and therefore do not close easily. In the early morning of summer, we can often see many small water droplets on the leaves of some plants, which are discharged from the water holes.
▋Flowers of plants - the "spokesperson" of beauty
In life, we often say that children are "flowers of the motherland", using flowers to describe beautiful youth; we often praise a girl who looks like a "flower" and describes her beauty... Flowers have simply become the "spokesperson" for all good things. However, the beauty of flowers is not only here, let's get to know the beautiful flowers!
The structure of the canola flower
The shape of the flower
The shapes of the flowers are varied. The blooming tulips are like small colored wine glasses, the blooming flower candles are like a delicate candlestick, the shape of the spring flowers is like a goblet used for drinking wine, the morning glory flowers are like small trumpets, and the bluebell flowers look like a string of chic bells...
The color of the flowers
The color of the flower is determined by the pigment in the petals. There are many kinds of pigments in the petals, the most important of which are flavonoids, carotenoids and anthocyanins. At present, more than 80 kinds of carotenoids have been found, and there are more than 500 kinds of flavonoids. Different kinds of carotenoids and flavonoids can make flowers appear different colors. Anthocyanins can also make flowers appear different colors in different acid-base environments.
Colorful flowers
The structure of the flowers
Most plants consist of four parts: calyx, petals, stamens, and pistils. At the top of the flower stalk are layers of beautiful petals. The outer circle of lobes on the outside of the petals is the calyx, which is usually green and consists of several sepals. The inside of the petals are stamens and pistils. The stamens consist of stigmas, peduncles and ovary, while the stamens consist of anthers and filaments.
corolla
The corolla is located on the inside of the calyx and consists of several petals arranged in one or more rounds. Usually the corolla has a bright and beautiful color, but there are also many plants whose corolla is white. Due to the different shapes and sizes of the corolla or petals, the petals are separated or combined with each other, so that the corolla forms a variety of different forms.
Different flowers have different corolla shapes
Classification of flowers
Flowers with only stamens or pistils are called unisexual flowers. Stamens and pistils grow within the same flower, called hermaphroditic flowers. Flowers that have neither stamens nor pistils are called asexual flowers, also called neutral flowers. Flowers with similar shapes and sizes, flowers with more than one symmetrical surface, are called symmetrical flowers, and vice versa are called asymmetric flowers. Flowers with calyxes and corolla are called heavy cover flowers; flowers with only calyxes or only corolla are called monocoma flowers; flowers that have neither calyxes nor corolla are called no quilt flowers.
inflorescence
The way the flowers of a plant are arranged on the branches according to a certain pattern is called an inflorescence. Flower branches are also called flower shafts, of which the main axis is germinated by the top bud, and the side axis is branched out by the axillary bud or branched out by the autonomous axis. According to the order of flower opening, the length of the main side axis and the branching condition, the inflorescence is usually divided into two categories: infinite inflorescence and finite inflorescence. Among them, the infinite inflorescence can be divided into a total inflorescence, an umbrella inflorescence, a spike-like inflorescence and a head-shaped inflorescence.
The aroma of flowers
Many flowers have an aroma because their petals are able to secrete aromatic oils with aroma. Because different flowers secrete different aromatic oils, the aromas they emit are also different. The aroma of osmanthus has a hint of sweetness, and the aroma of orchid is light and fresh. Compared to the color of the flowers, the aroma of the flowers is more attractive to insects, because the insects can smell from a long distance.
The aroma of the flowers attracts small insects
▋ Pollen - the "elf man" who fell from the sky
In summer, the garden is full of flowers and fragrance. A gust of wind blows, one "little elf" after another flying, when they find the "favorite" flower, they will not hesitate to fall into it, new life began to sprout... Who are these "elves"? What role do they do to nurture new life? Let the pollen unravel all the puzzles!
Anthers and pollen of curly dan
The shape and color of pollen
There is a lot of pollen growing on the stamens of the flowers, which is a reproductive structure unique to gymnosperms and angiosperms. The shape of pollen is prickly, granular, nodular, mesh, line mass, pore and so on. For example, the pollen of rice and corn is spherical; the pollen grains of cycad and ginkgo biloba are like small boats. The most common colors of pollen are golden yellow and orange yellow, which is due to the fact that the outer wall of pollen contains more carotenoids and flavonoids. In addition, pollen is also available in green, blue and red.
The pollen of peach blossoms and lotuses is yellow
The size of the pollen
Most pollen grains are less than 80 microns in diameter. The diameter of rice pollen grains is 42 to 43 microns, and the diameter of peach pollen grains is 50 to 57 microns, which can only be seen clearly under the microscope. The smallest known pollen is the pollen of the forget-me-not grass, and the largest pollen is the pollen of zucchini.
Bees spread pollen while collecting honey
The function of pollen
Without the spread of pollen, plants would not have seeds and even fruits would not have developed. Pollen plays an important role in the succession of plants. In addition, fresh pollen is rich in protein, amino acids, vitamins, trace elements and other nutrients, which is called a "concentrated nutrient library".
Spread of pollen
After the plant flowers, the mature pollen on the stamens anthers is transmitted to the pistil stigma through various media, a process called pollination. Pollination is an indispensable part of plant reproduction, and its methods include self-pollination and cross-pollination. Among them, cross-pollination has several methods such as wind-media pollination, water-borne pollination, insect-borne pollination, and bird-media pollination.
Wind media pollination
The method of transmitting pollen by wind is called wind pollination. Poplars, oaks, birches and most of the grasses are wind-borne plants, and their flowers are called wind-borne flowers. The pollen of the wind-borne flowers is smooth, dry and lightweight, making it easy to be blown by the wind.
Waterborne pollination
The way pollen is transmitted with the help of water is called waterborne pollination. Aquatic plants basically rely on water medium to complete pollination. There are two cases of waterborne pollination: one is water pollination, such as black algae and bitter grass and other plants, their pollen matures, floating on the surface of the water, due to the turbulence of the water surface, the male flowers will pass the pollen to the pollen to the female flower; the other is underwater pollination, such as goldfish algae. In addition, there is a kind of rain medium flower, the flower does not close when it rains, and the rainwater flows to pollinate.
Insect vector pollination
The way insects transmit pollen is called insect pollination, and the flowers that rely on insect pollination are called insect pollination flowers. Insect-borne flowers adapted to insect pollination generally have bright colors, aromatic odors, and sweet honey juices. In addition, the pollen of insect-borne flowers is large, the surface is rough and protruding, and some even stick into pieces, attached to the insect, easy to carry.
Bird pollination
Much of the pollen is spread by birds, which we call bird pollination. There are about 2,000 species of birds in the world pollinators for flowers, the most important pollinators are hummingbirds, sunbirds, flowerpeckers and so on. Typical bird-borne flowers have the following characteristics: the flower is in a more conspicuous position; the flower color is mostly the red or orange that can mostly attract birds; the flowering period is long, generally opening during the day; and the amount of nectar secreted is large.
▋ The fruit of the plant - the harvest of autumn
In addition to giving us the enjoyment of beauty, the plant also provides us with delicious fruit. When autumn comes, along with the yellow leaves, there is not only a refreshing aroma, but also a fruitful fruit of plants. So, where did the fruit come from? And what is it used for? Now, let's take a look!
The production of fruits
Fruit is an organ of a plant whose flowers are pollinated and fertilized by a certain part of the pistil. It is a reproductive organ peculiar to angiosperms. The fruit developed from the lower part of the pistil in the flower, the ovary, is called the true fruit, such as peach, plum and so on. Fruits that develop from other parts such as calyxes, flower holders, or flower quilts are called false fruits, such as apples, pears, and pomegranates.
The color, shape and size of the fruit
When the fruit of the plant is not yet ripe, it is usually green, and when it is ripe, it will turn into bright colors such as red and yellow. The shape and size of the fruit are also diverse, such as: watermelon, apple, cherry, orange, etc. are spherical; kiwis, mangoes, dates, etc. are oval; bananas look like large hands. Some fruits are small, not as big as fingers; some fruits are very large, weighing tens of kilograms.
Many fruits are spherical in shape
The structure of the fruit
The fruit consists of two parts: the peel and the seed. The peel is divided into three parts from the outside to the inside: the outer peel, the middle peel and the inner peel. In the case of peaches, the layer of peach peel that we cut off is the outer peel, the thick and juicy peach flesh that we eat is the middle peel of the peach, the hard peach core is the inner peel, and the inside of the peach pit is the seed.
The structure of the peach
The taste of the fruit
Different fruits have different tastes such as sour, sweet, bitter, and spicy due to the different chemicals contained in the cells. If the fruit has more acidic content in cells, then it will be more acidic; if the fruit has more sugar content in cells, then it will be sweeter.
The type of fruit
Plant fruits are diverse, and according to the different water contained, they can be divided into two categories: fleshy fruits and dried fruits. Flesh fruits, also known as juicy fruits, commonly known as fruits, they have a lot of water content, bright color, sweet flesh, such as apples, peaches, pears, grapes, etc.; dried fruits have dry and hard shells on the outside, and the seeds are breaded inside, such as chestnuts, hazelnuts and sunflower seeds.
fruit
When the fruit is ripe, the skin flesh becomes fleshy, becomes thick and contains more water, and its epidermis is not easy to crack, such as juicy peaches, fragrant apples, sweet and sour grapes, refreshing watermelons, etc. The fruit is bright in color and sweet in taste, and common types include stone fruits, berries, citrus fruits, and urn fruits.
Peaches are a fruit we often eat
dried fruit
When the fruit is ripe, the peel is heavily dehydrated, and the fruit that becomes dry and hard is called a dried fruit. According to whether the fruit is cracked after ripening, dried fruit can be divided into split fruit and closed fruit. When ripe, dried fruits whose skins can crack are cracked, and those that do not crack are closed fruits. Dried fruits contain a variety of nutrients that are beneficial to the human body, which can be described as a treasure trove of nutrition.
A wide variety of dried fruits
Fruits and seeds
Flowering results are an important part of the plant's life cycle. The seeds are derived from ovules in the ovary, which contain the embryos that create new life, which is the beginning of plant life. The fruit wraps the seed together, which helps to protect the seed from harm.
▋ Seeds of plants - "little man" with a long way to go
Speaking of seeds, whether it is its "size" or form, it is difficult to attract everyone's attention. However, it is such a "small man" whose position in the plant kingdom cannot be ignored. Although it is not amazing, it carries the arduous mission of continuing the life of the plant family.
The shape of the seed
Seeds are endemic organs of gymnosperms and angiosperms and bear the burden of reproducing offspring. Plant seeds come in a variety of shapes: spherical, such as pea seeds; heart-shaped, such as peach seeds (i.e., peach cores); kidney-shaped seeds, such as cowpea seeds; oval seeds, such as peanut seeds; and triangular, diamond-shaped, and so on.
The color and appearance of the seeds
The color of the seeds is mostly black or brown, but there are other colors. For example, the seeds of legumes have black, red, green, white, yellow and other colors. The appearance of the seeds is varied, some are smooth, some are rough, some have hairs on the surface, and some have thorns on the surface.
The size of the seed
Different seeds also vary greatly in size, some are larger than a ball, and some are as small as dust. For example, the seeds of the leaves are large, up to 20 cm in diameter; the seeds of plants such as rapeseed and sesame seeds are small; and the seeds of tobacco, purslane and orchids are even smaller.
Most plants have small seeds, and the seeds of pomegranates are the seeds inside the pomegranate fruit
The structure of the seed
Seeds are composed of three parts: seed coat, embryo and endosperm. The seed coat is developed from beads, the main role is to protect the embryo and endosperm; the embryo is developed from the fertilized egg, and the fully developed embryo is composed of radicles, hypocotyls, germ and cotyledons, which will develop into various parts of the plant in the future; endosperm is responsible for providing nutrition for the growth and development of seeds.
The lifespan of the seeds
The lifespan of seeds is generally relatively short, for example, the seeds of the cocoa tree lose the ability to germinate after about 35 hours away from the mother. If the seed can live for more than 15 years, it is already considered a long life. But there are also some seeds that live a long time. For example, the ancient lotus seed discovered in 1952 in Liaoning Province, China, has been sleeping for more than 1,000 years, and after being cultivated by scientists, it can still flower and bear fruit.
Conditions for seed germination
Seeds are the source of life for plants. Whether it is a big tree or a small grass, it starts with a seed. However, seed germination requires certain environmental conditions, mainly sufficient moisture, suitable temperature and sufficient oxygen. Dried seeds can only grow adequately if they absorb enough water, at a suitable temperature and with sufficient oxygen.
The growth of seeds
When the seeds germinate, the embryo cells begin to divide and grow. First, the radicle breaks through the seed coat and sticks into the soil; then, the germ also begins to grow, breaking through the seed coat, and soon differentiates into young shoots and leaves. Initially, young shoots and young leaves are white, and when chlorophyll is formed, they begin to photosynthesize to make the nutrients needed for growth. At this time, the seed coat falls off and the seed grows into an independent seedling.
Spread of seeds
After the plant seeds mature, they do not all fall on the nearby ground, but use various methods to spread to a wider place and expand the field of reproduction. There are two main ways for seeds to spread: one is to spread by means of external forces, such as wind, water, animals and humans; the other is to rely on their own strength to spread.
The process of seed germination
▋ Vegetative propagation of plants - the breeding method of "another way"
Plants have been able to survive from billions of years ago to today, mainly due to their unique way of reproduction. For most plants, seeds are the key to their reproductive offspring, but there are also some plants that "go a different way" and use roots, stems, buds, and leaves to reproduce, which is called vegetative reproduction.
Plants that multiply from roots
Some plants can be propagated with roots. In the case of sweet potatoes, for example, in the spring, the roots of the sweet potatoes are buried in the soil, and soon the roots grow new shoots. When the bud grows into a vine more than ten centimeters long, cut it off and insert it in the soil to grow roots, stems and leaves, becoming a new sweet potato.
Plants that multiply on stems
Some plants can reproduce with stems, such as the underground tuber of a potato, which reproduces in a similar way to sweet potatoes. In addition, plants such as strawberries and hanging orchids have vine-like walking stems, and the walking stems are full of buds. Initially, the mother plant supplies nutrients to new shoots through the vines. After the new shoots take root, they can absorb nutrients from the soil and gradually grow into an independent plant.
Plants that reproduce with adventitious buds and leaves
Some plants have small adventitious buds on their leaves. When the leaves of these plants fall to the ground, the adventitious bud wine paints fine roots and grows into a new plant, such as a yellow lily. Plants of the Begonia family can reproduce with their leaves.
Some plants are propagated with adventitious buds or leaves
Artificial propagation methods
In addition to the propagation method of the plant itself, people have successfully achieved artificial reproduction according to the characteristics of various parts of the plant body, including roots, stems, leaves, buds, etc., which can become the carrier of the plant's reproductive offspring. Among them, the more commonly used artificial propagation methods are splitting, grafting, cuttings, pressing strips and so on.
Divide the plants
The propagation method of rooting new individuals from the mother is called the branching method. The branches are used in clumps or shrubs or root-prone plants that are prone to germination, such as platycodon and garlic, which can be propagated in this way. When dividing the plant, be careful not to break the branches and buds. If the roots are too tight, they can be cut open with scissors. The number of plants should be determined according to the size of the mother plant and the number of roots.
graft
The grafting method refers to the reproductive method of attaching a part of a plant body to another plant body, and its tissues are healed by each other and cultivated into independent individuals. The grafted roots and stems are called rootstocks, and the grafted branches, shoots, or roots are called scion. Generally speaking, the grafting method can be divided into three types: grafting method, budding method and rootgrafting method.
cuttage
Cuttings, called cuttings, refer to the propagation method of cutting off the roots, stems, leaves and other parts of the plant, inserting them into the soil or sand at a vertical or oblique angle, or submerging in water, so that it takes root and grows into a new plant. In general, cuttings include stem cuttings, leaf cuttings, root cuttings and bud cuttings. Different plant cuttings require different conditions, understand and adapt to their conditions, in order to obtain a higher reproductive success rate.
layering
Sometimes people wrap the branches of the plant with soil or other substances, wait until the roots grow, and then cut off and divide the plant from the mother plant, this method of reproduction is called the striping method. Usually, the strip pressing method can also be divided into several types, namely bending method, stacking method, ditch pressure method and high pressure method.
▋ Survival skills of plants - "Eight immortals across the sea, each showing their magic"
In the TV series "Eight Immortals Crossing the Sea", the most classic plot is a section of eight immortals flying across the East China Sea to Penglai Immortal Island. At the suggestion of Lü Dongbin, the immortals did not take a boat, but crossed the sea with their own skills, which was really eye-opening. However, in the plant world, there are not only eight "immortals", and the survival skills of plants are far more than the tricks of "eight immortals crossing the sea".
disguise
Some plants use camouflage to protect themselves, and some plants use camouflage to attract insect pollination. For example, the raw stone flowers that grow on the rocky beach are like pebbles in shape, color, and size, so as to avoid external damage; the flowers of the leaf orchid look like a female bee, which can attract a large number of male bees, and the male bees try to mate with the flowers, but actually pollinate the flowers.
Ye Lan disguised as a female bee
Spikes
Many plants have hard thorns, such as spikes, roses, thistles, cacti, etc. These thorns protect plants from enemies. For example, sparrows in the fields do not dare to touch the spikes with thorns, and the hungry animals in the desert are afraid of the cacti with small thorns. The best thing to protect yourself with spikes is nettle. As the animal passes by the nettle, the spines stick to the animal and then inject an acidic liquid into the animal's skin, causing pain. In this way, nettles are able to avoid being swallowed by animals.
mucus
Some plants secrete a sticky fluid, such as peach trees that secrete peach gum and pine trees that secrete pine resin. Slime is also a weapon of plant self-defense. When aphids that like to steal tree sap crawl over, they are often stuck to the slime, as if they are firmly bound by a rope, and can no longer escape.
Toxic substances
In addition to spikes and mucus, some plants use toxic substances to protect themselves. For example, the sap of oleander contains toxins, and insects will die when eaten; tobacco and water parsley not only contain toxins, but also emit unpleasant odors, and some animals will not come back after their first visit.
parasitism
Some plants do not photosynthesize, but specifically take nutrients from other plant bodies, this plant is called parasitic plants, such as mulberry parasitism, silk seeds and so on. Parasitic plants themselves cannot live independently, and must be invaded by special organs, the suction device, to seize the water and nutrients of other plants to maintain life.
symbiosis
Two plants live together, interdependent, mutually beneficial in their survival, and are called symbiosis. Lichens are symbiotic plants. Fungi use hyphae to absorb water and inorganic salts, which are then supplied to algae, which use chlorophyll for photosynthesis to make organic matter and provide the fungus with nutrients necessary for survival.
Epiphytes
Some plants do not come into contact with the soil, their roots are attached to the branches of other trees, and they live on rain, dew, and limited humus (decaying dead branches and leaves or animal excrement, etc.), such as ferns and orchids. These plants are called epiphytes, and they can photosynthesize themselves and do not rob them of the nutrients and water of the plants they depend on.
▋ Plant Growth Campaign - "Family Mobilization."
Unlike humans and animals, plants cannot move at will, but the various parts of the plant body are always in constant motion: the roots grow thicker and thicker underground, the longer and longer they are; the stems are longer and thicker, longer and taller; the branches and leaves are longer and larger, longer and denser; the flowers are more beautiful and moving... It is in this movement that plants gradually grow and grow.
The secret of growth
The plant body is made up of cells, so the growth of plants is actually the growth and reproduction of cells. As plants grow, new cells are constantly produced, and new cells continue to grow. A tree that has grown for thousands of years also starts from a seed, constantly produces new cells, and then new cells continue to grow.
Growth-promoting substances
The substance that promotes the acceleration of plant growth is called auxin. Auxin forms at the tip of the growing stem and then moves downwards. When the light on the left and right sides are the same, auxin is evenly distributed in the stem of the plant. However, when one side has stronger light, auxin accumulates on the side with weaker light, causing that side to grow rapidly.
The growth movement of the roots
Cells at the root front growth point will continue to divide, while cells in the elongation zone located above the growth point will continue to elongate. The growth of roots is accomplished by the division of the cells at the point of growth, and the elongation of new cells produced by division. Different plants and different soil conditions will affect the growth form of the roots. For example, some plants have hypertrophic tapers and lateral roots, and some plants have only tiny whisker roots.
Growth movement of the stem
Once the stems of herbaceous plants have grown to a certain extent, they stop growing. The stems of woody plants can continue to grow tall and thick. The stems of woody plants, in addition to having growth points at the apex, also have a forming layer on the inside of the epidermis. The forming layer can constantly produce new cells and grow, so that the stem can continue to thicken.
Growth movement of leaves
Leaf growth is first longitudinal growth, followed by horizontal expansion. Cell division and volume increase of the apical meristem of young leaves promotes an increase in leaf length. Subsequently, cell division differentiation and volume increase of the marginal meristem of the young leaf can expand the surface area and thickness of the leaf. In general, the leaf tip and base mature first, and the growth stops early; the leaf margin cell division lasts for a long time, constantly producing new cells and expanding the leaf surface area. When the leaves are fully unfolded, they no longer expand their growth, but maintain normal physiological functions for a considerable period of time. The largest leafy plant in the world is the large root Nella grass, and the smallest leaf plant is the cypress.
Flower growth movement
The growth movement of flowers is mainly reflected in the blossoming and closing of flowers. The expansion coefficient of the outer skin cells in the petal is different, when the external temperature rises, the expansion inside the petal increases, resulting in the inner epidermal cells (the inside of the petal) growing fast, so the petals bend outward, and the flowers bloom. By the same token, when the outside temperature drops, the flowers close.
Growth movement of tendrils or vines
The tendrils of the morning glory are wrapped around the object and are also a growth movement. During the growth process, the tendrils of morning glory will surround them once they touch objects such as sticks, slowly bending and stretching. The front end of the tendrils grows continuously, and the lower tendrils spiral around the sticks. There are many plants where vines or tendrils can move, such as cucumbers, loofahs, etc.
The tropic movement of plants
Under the unidirectional stimulation of external factors such as light, gravity, water and chemicals, the directional growth movement produced by plants is called directed growth movement. According to the different directional movements of external stimuli, it can be divided into phototropism, geotropism, waterward and tropic. Among them, the ability of plants to bend with the direction of light is called phototropism. The plant is placed horizontally, and due to gravity, the root bends downward to grow, which is called geoscience.
▋ Photosynthesis - have a "date" with the sun
The growth of any organism must take in a certain amount of nutrients. Humans and animals absorb nutrients from food through the digestive system, and for plants without a digestive system, they must rely on a unique way to achieve nutrient intake. This unique way is inseparable from the help of the sun, which has a beautiful name - photosynthesis.
Discovery of photosynthesis
In 1771, the British scientist Priestley discovered that the lit candle was placed in an airtight glass cover along with green plants, and the candle was not easy to extinguish. Therefore, he pointed out that plants can renew the air. In 1880, the German scientist Engelmann conducted experiments on photosynthesis with sponges, and finally concluded that oxygen is released by chloroplasts, which are the places where green plants photosynthesize.
What is photosynthesis
Photosynthesis refers to the process by which plants use sunlight to convert inorganic substances such as carbon dioxide and water into organic matter and release oxygen. Photosynthesis includes two stages: photoreaction and carbon reaction. The photoreaction and carbon reaction should cooperate with each other to complete the photosynthesis of plants.
Light reaction
After the plant absorbs light energy, the light-excited chlorophyll molecules release high-energy electrons, and the light energy is converted into electrical energy; water, as the electron donor of chlorophyll, decomposes under the action of light, releases hydrogen ions and oxygen, and eventually turns light energy into active chemical energy, producing high-energy substances in biological metabolism. This process is the light response. Light reactions are caused by light and need to be carried out under the action of light.
Carbon reaction
Carbon reaction is the process of converting carbon dioxide into carbohydrates in photosynthesis. It uses the two high-energy compounds generated by the light reaction as energy and reducing power respectively, fixes the absorbed carbon dioxide, and converts it into organic matter such as glucose. Since this process does not require light, it is also called dark reaction.
External factors that affect photosynthesis
Light is the driving force of photosynthesis, and its intensity directly restricts the intensity of photosynthesis. Carbon dioxide is one of the raw materials for photosynthesis, which is mainly absorbed from the air by the leaves. Under conditions where light is limited, increasing the concentration of carbon dioxide can increase the intensity of photosynthesis. Under the conditions of high concentration of strong light and carbon dioxide, the effect of temperature on the intensity of photosynthesis is more obvious.
chlorophyll
Chlorophyll is the main pigment contained in the body of green plants and plays an extremely important role in the process of photosynthesis of green plants. The first part of plant photosynthesis must be the chlorophyll in the plant body receiving light energy, and then inorganic substances such as carbon dioxide and water can be converted into organic matter.
Plants capture sunlight through chlorophyll
The meaning of photosynthesis
The photosynthesis of plants has important significance. It converts solar energy into chemical energy, converts inorganic matter into organic matter, absorbs carbon dioxide, and releases oxygen. Because of the photosynthesis of plants, the oxygen and carbon dioxide in the atmosphere can be relatively balanced, and the organisms on the earth can survive and develop.
▋ Respiration - "Oxygen War"
In life, people like to place a variety of potted plants indoors, on the one hand, to decorate the room, on the other hand, they value that plants can produce oxygen and purify the air. However, plants do not always selflessly give oxygen, at some point, they will even engage in an "oxygen war" with humans...
Respiration affects the progress of plant life activities
What is respiration
Like humans and animals, plants breathe. We take the process by which organisms absorb oxygen, decompose organic matter into carbon dioxide and water, and release energy, called respiration. Respiration continuously decomposes the substances in the plant's body and provides energy for the plant body to carry out various life activities.
The process of respiration
Like photosynthesis, respiration can be divided into two phases. The first stage occurs in the cytoplasm, where glucose is initially broken down into small molecules by enzymes, releasing a portion of the energy; the second stage occurs in mitochondria, where small molecules are further broken down into smaller molecules and release carbon dioxide, water, and energy.
Aerobic breathing
Humans and animals need oxygen for breathing, and in the same way, most plants need oxygen to participate in the breathing process. The breathing process in which oxygen is involved is called aerobic respiration, and it is the main way plants breathe. The end products of aerobic respiration are carbon dioxide, water, and more energy.
Anaerobic breathing
Unlike humans and animals, plants can also undergo short-term anaerobic respiration in an oxygen-deprived environment, such as when submerged by water. Anaerobic respiration cannot completely oxidize organic matter into water and carbon dioxide, but can only decompose into alcohol and carbon dioxide, releasing less energy.
Anaerobic respiration is a way of life that makes plants more intelligent than animals
Comparison of respiration and photosynthesis
Respiration and photosynthesis are both closely related and have certain differences. There are mainly the following points: First, photosynthesis is limited to plants and occurs only in the green cells of plants, while respiration occurs in every cell of animals and plants. Secondly, photosynthesis must be carried out under conditions of sunlight, and respiration and light are not light. Third, photosynthesis uses water and carbon dioxide as raw materials to release oxygen, while respiration uses organic matter and oxygen to release water, carbon dioxide and energy. Fourth, photosynthesis converts the sun's radiant energy into chemical energy and stores it in plant bodies, while respiration converts chemical energy in organisms into thermal energy. Fifth, the result of photosynthesis is to increase organic matter, and respiration is to reduce organic matter.
Relationship between respiration and photosynthesis
When plants photosynthesis, they absorb carbon dioxide and expel oxygen, at this time the carbon in carbon dioxide is stored in starch, and the carbon emitted during breathing is the carbon in starch. When plants breathe, starch breaks down into carbon dioxide and water and releases stored energy. Photosynthesis and respiration can be seen as two interdependent processes that form a cycle that ensures relative stability in the atmospheric oxygen and carbon dioxide levels.
Significance of respiration
The most important physiological significance of respiration is to provide indispensable energy for the plant body to carry out various physiological activities; to provide raw materials for the synthesis of other organic matter in the plant, such as the intermediate products formed by starch in the process of respiration, which can be converted into proteins and fats; to provide power for the metabolism of the plant body; and to enhance the immunity of plants.
▋ Transpiration - plants "sweat"
When watering flowers, do you wonder why a small plant needs much more water than its body? Can it be "drunk"? The study found that only a small part of this water was absorbed by the plant, while most of it evaporated from the plant like "sweat". Of course, this process is not called "sweating", but has a nice name, called "transpiration".
Transpiration of plants
What is transpiration
Water from the soil enters the root from the root hairs and is then transported through the catheters of the roots, stems and leaves to the mesophyll cells containing chlorophyll. In addition to a small part of these waters participating in various life activities in the plant, most of them become water vapor, and are mainly emitted into the atmosphere through stomata, this process is called the transpiration of plants.
The stomata are steaming
The surface of the plant leaves is distributed with a large number of stomatals, although these stomatals are small, all stomata occupy less than 1% of the leaf area, but the water lost through the stomatals is very large, accounting for more than 90% of the entire transpiration. Therefore, the main way of transpiration is stomata transpiration.
Transpiration with plants
Transpiration has important implications for plants: first, it can lower the temperature of the plant body to avoid burning the leaves due to sunlight exposure; second, it can promote the absorption of water by the roots and the transport of water and inorganic salts in the plant.
Transpiration and climate
The transpiration of plants regulates the climate. Above the woodland where a large number of plants grow, the air humidity is 15% to 25% higher than other places, and the precipitation will be correspondingly much higher.
▋ Plants and water and soil - no one can do without anyone
Water and food are essential for human survival; for plants, in addition to sunlight, water and soil are absolutely indispensable. Without water and soil, there can be no plants; in turn, water and soil have a certain dependence on plants. So, what kind of close relationship do they have?
Plant bodies and water
Water is an important component of the plant body, and the water content of the plant body is related to the characteristics of plant species, growth environment and organs. Different plants have different water content, for example, aquatic plants such as duckweed have a water content of more than 90%, while the water content of lichen growing in an arid environment is only about 6%.
Plants grow with water
The growth of plants varies greatly in areas with different amounts of precipitation. Plants that grow in arid areas have longer roots and smaller leaves, while plants that grow in moist areas have shallower roots and spread outwards, with many branches and leaves, and relatively large leaves.
Soil species with plants
The soil is a mixture of clay, sand and humus. According to the pH, the soil can be divided into acidic soil, alkaline soil and neutral soil. Red pine, wattle, water moss, etc. are suitable for acidic soils; spinach, lentils, cabbage, etc. are suitable for alkaline soils.
Soil-plant interactions
The soil contains many trace elements and inorganic salts that provide the nutrients needed for plant growth. The dead branches and leaves of plants, as well as animal excrement and corpses, decompose to form humus, which can improve the quality of the soil.
▋ Plants and Seasons – Nature's Clock
In the history of human development, the way people record time, from the earliest determination of the approximate time by the position of the sun, to the appearance of sundials and hourglasses, to the invention of modern high-tech clocks, the recording of time has become more and more accurate. However, in nature, there is a different kind of "clock", which is not controlled by humans and accurately shows the changes of the seasons. It is a plant.
The relationship between plants and seasons
Plants take on different faces in different seasons. In temperate regions with four distinct seasons, each season has a representative plant, and we can know which season it is based on the characteristics of plant growth. In the tropics, the seasonal characteristics of plants are not obvious.
The four seasons of the year
In the spring, the plants begin to grow and sprout, and as the temperature rises further, the colorful flowers open and the trees gradually turn green; in the summer, the plants grow more vigorously and the trees become more lush; in the autumn, some leaves begin to turn yellow or red; in the winter, many trees become bare, and only the evergreen trees remain green. Most plants repeat their entire lives according to this pattern.
Plants change from season to season
Seasons with sowing
Some plants are suitable for spring planting, April and May is their growth period, summer began to germinate, flower, autumn fruit, such as hydrangeas, morning glory and so on. Some plants are suitable for planting in autumn and winter, they grow particularly slowly in the winter, and begin to grow vigorously in the spring of the following year, and bloom in the summer, such as pansies, caryophyllus, etc.
Seasons and flowering periods
Each season has a different kind of flower blooming, and the time when each flower blooms to the time it falls is called the flowering period. In the same region, the flowering period of the plant is certain. But if the same plant grows in different regions, the flowering period will vary greatly.
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Source: Youth Science Horizons: Plants