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Characteristics of gymnosperms Gymnosperms are a large group of plants with evolutionary status between ferns and angiosperms, most of which produce seeds and have vascular bundles while retaining the neck

author:Brother Rabbit Encyclopedia

Characteristics of gymnosperms

Gymnosperms are a large group of plants with an evolutionary status between ferns and angiosperms, most of which can produce seeds, have vascular bundles, but retain the cervical ovipos, which is a class of higher plants.

The main characteristics of gymnosperms are as follows

1. The sporophyte is very developed The sporophyte plant is very tall, basically a perennial woody plant, with a developed true root, and the root system is very developed; The branches are divided into long and short branches, with forming layers and secondary tissues, xylem and phloem, and middle column; The leaves are needle-like, scaly, strip-like, rarely broad-leaved; The leaves of the sporophyte are often arranged spirally on long branches and clustered on short branches; Also, gymnosperms have many light-colored stomatal bands and are arranged in multiple strips.

2. Although gametophytes are degraded, they retain the cervical oovipositor Most gymnosperms retain the cervical ovipos, although this cervical oocyte is already simpler than ferns, and the gametophyte has degenerated to the point that it can only remain on the sporophyte, gymnosperms and ferns are very different.

3. Ovules are exposed Unlike the epithelial coating evolved from large spore leaves, the ovules of gymnosperms are exposed.

4. Pollination pollen directly reaches the ovule The bead hole of the gymnosperm ovule can secrete mucus, stick the transmitted pollen, after the mucus dries, the pollen enters the ovule first pauses in the pollen storage room, and then germinates the pollen tube, with the help of the pollen tube into the blastocyst and egg combined fertilization. Angiosperms need pollen to germinate pollen tubes at the pistil's stigma, and the pollen tubes penetrate deep into the pollen column and pass through the beads to enter the blastocyst, along which the pollen can enter the blastocyst and combine with the egg to form a fertilized egg.

5. Polyembryonic phenomenon The vast majority of gymnosperms have multiple embryonic phenomena: multiple eggs in multiple cervical oviolea on a female gametophyte fertilize to form multiple fertilized eggs is called simple polyembryonic phenomenon; When a fertilized egg develops, it splits to produce multiple fertilized eggs, which is called the phenomenon of splitting multiple embryos.

6. Able to produce seeds The ovules of gymnosperms develop into seeds, and the beads are developed into seed coats, and the seeds are complete sporophytes with nutrients such as endosperm. The seeds help plants survive harsh environments and germinate into Gundam plants when the time is right.

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Characteristics of gymnosperms Gymnosperms are a large group of plants with evolutionary status between ferns and angiosperms, most of which produce seeds and have vascular bundles while retaining the neck
Characteristics of gymnosperms Gymnosperms are a large group of plants with evolutionary status between ferns and angiosperms, most of which produce seeds and have vascular bundles while retaining the neck
Characteristics of gymnosperms Gymnosperms are a large group of plants with evolutionary status between ferns and angiosperms, most of which produce seeds and have vascular bundles while retaining the neck
Characteristics of gymnosperms Gymnosperms are a large group of plants with evolutionary status between ferns and angiosperms, most of which produce seeds and have vascular bundles while retaining the neck
Characteristics of gymnosperms Gymnosperms are a large group of plants with evolutionary status between ferns and angiosperms, most of which produce seeds and have vascular bundles while retaining the neck
Characteristics of gymnosperms Gymnosperms are a large group of plants with evolutionary status between ferns and angiosperms, most of which produce seeds and have vascular bundles while retaining the neck
Characteristics of gymnosperms Gymnosperms are a large group of plants with evolutionary status between ferns and angiosperms, most of which produce seeds and have vascular bundles while retaining the neck
Characteristics of gymnosperms Gymnosperms are a large group of plants with evolutionary status between ferns and angiosperms, most of which produce seeds and have vascular bundles while retaining the neck
Characteristics of gymnosperms Gymnosperms are a large group of plants with evolutionary status between ferns and angiosperms, most of which produce seeds and have vascular bundles while retaining the neck
Characteristics of gymnosperms Gymnosperms are a large group of plants with evolutionary status between ferns and angiosperms, most of which produce seeds and have vascular bundles while retaining the neck
Characteristics of gymnosperms Gymnosperms are a large group of plants with evolutionary status between ferns and angiosperms, most of which produce seeds and have vascular bundles while retaining the neck
Characteristics of gymnosperms Gymnosperms are a large group of plants with evolutionary status between ferns and angiosperms, most of which produce seeds and have vascular bundles while retaining the neck
Characteristics of gymnosperms Gymnosperms are a large group of plants with evolutionary status between ferns and angiosperms, most of which produce seeds and have vascular bundles while retaining the neck
Characteristics of gymnosperms Gymnosperms are a large group of plants with evolutionary status between ferns and angiosperms, most of which produce seeds and have vascular bundles while retaining the neck
Characteristics of gymnosperms Gymnosperms are a large group of plants with evolutionary status between ferns and angiosperms, most of which produce seeds and have vascular bundles while retaining the neck
Characteristics of gymnosperms Gymnosperms are a large group of plants with evolutionary status between ferns and angiosperms, most of which produce seeds and have vascular bundles while retaining the neck
Characteristics of gymnosperms Gymnosperms are a large group of plants with evolutionary status between ferns and angiosperms, most of which produce seeds and have vascular bundles while retaining the neck

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