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High school electives are the first semester chemistry review materials
Chapters 1-2
Every little attention
Can bring you closer to the full score
1
Focus on nutritional balance
Review the key points
1. The basic energy of life - sugars
2. Important energy source in the body - oil
3. The basis of life - protein
4. Vitamins and trace elements
Special reminder
1. Sugars are the products of photosynthesis of green plants. A class of organic compounds composed of three elements of C, H and O, also known as carbohydrates
2. Glucose molecular formula C6H12O6 is a kind of white crystal, which has a sweet taste and can be soluble in water
3, glucose provides energy for the human body
(1) The equation for glucose to provide energy:
(2) The sugars in grain are converted into glucose in the human body and absorbed, and there are three ways in the body, namely:
a. Direct oxidation and energy supply
B, converted into glycogen is stored by the liver and muscles, when the glucose in the blood, that is, the mass fraction of blood glucose is lower than normal, glycogen is released to maintain a relatively stable blood glucose concentration
C. Converted into fat and stored in adipose tissue
4, starch is an important polysaccharide, is a relatively large molecular mass of natural polymer organic compounds, no sweetness, is a white powder, insoluble in cold water, but in hot water part of the starch dissolved in water, part suspended in water, long time or high temperature can produce gelatinization. It can be hydrolyzed
5, cellulose is generated by green plants through photosynthesis, is the basic substance that constitutes plant cells, it is a white, odorless and tasteless substance, is a polysaccharide, belongs to natural organic polymer compounds
Cellulose undergoes hydrolysis catalyzed by enzymes or concentrated sulfuric acid
Fiber can not be used as a nutritious food for humans, but it is indispensable in the human body, such as: it can stimulate intestinal peristalsis and secrete digestive juices, which helps the excretion of food and waste products
6. Oils and fats are esters produced by higher fatty acids and glycerol, the same glycerides are called monoglycerides, and different glycerides are called mixed glycerides. Natural oils and fats are mixed glycerides and are mixtures
7, the composition of oil: at room temperature is a liquid state of higher fatty acids glycerol esters called oil, solid called fat, they are collectively referred to as oil. The more unsaturated bonds contained in the hydrocarbon base of the oil molecule, the lower the melting point. The density of grease is smaller than that of water and is insoluble in water
8. The four main functions of fatty acids in the human body: supplying human heat, storing energy, synthesizing raw materials for substances needed by the human body, and essential fatty acids have a variety of physiological functions in the body
9. The molecule of amino acids contains both amino groups and carboxyl groups, which can react with acids and alkalis to generate salts, and its general formula is (refer to textbooks)
10. The constituent elements of protein are C, H, O, N, which are natural organic polymer compound compounds composed of amino acids through dehydration and condensation, with two sexes. The building blocks of protein are amino acids
11, vitamins are involved in biological growth and development and metabolism necessary for a class of small molecule organic compounds, customary according to different solubility, they are divided into fat-soluble vitamins (mainly including vitaminS, D, E, K) and water-soluble vitamins (mainly including vitamin C, vitamin B group)
12, the content of trace elements in the human body is very small, the quality is less than one ten thousandth of the body weight, such as Fe, I, Se, etc. A total of 16 kinds, while the constant elements refer to the content of more than 0.01% of the elements, such as C, H, O and a total of 11 kinds
13, the content of iron in the human body is about 4-5g, which is the most important of the essential trace elements in the human body. Iron-containing compounds in the human body are mainly divided into two categories, namely functional iron and stored iron, which participate in the transportation of O2 together, iron deficiency can be supplemented by iron-fortified soy sauce, the reason why soy sauce is used as a carrier for iron-fortified food, this is mainly because soy sauce can promote iron absorption, and has a wide range of mass consumption bases, in addition, people's daily intake of soy sauce is stable in a relatively reasonable range of values
2
Promotes physical and mental health
Review the key points
1. Reasonable choice of diet
2. Correct use of the drug
Special reminder
1, water is an important component of the human body, accounting for about two-thirds of the human body weight, its main role is a good solvent, reaction medium and reactants, regulate body temperature
2, the acidity and alkalinity of food and the chemical referred to in the solution is not the same, he refers to the acidity or alkalinity of food, is classified according to the nature of the final product of food metabolism in the body
3. Common food additives are classified as colorants, preservatives, flavoring agents and nutritional additives
Colorants mainly include: carotene, annatto, amaranth red, lemon yellow. The preservatives used in the early days were mainly salt, vinegar, sugar, etc
Now commonly used preservatives are sodium benzoate, nitrate, nitrite, sulfur dioxide
4. Synthetic drugs mainly include antipyretic analgesics, antibiotics and antacids
5, aspirin is well known as a cold medicine, has antipyretic and analgesic effect, its chemical name is acetylsalicylic acid, is the first important synthetic drug, the structural formula is (reference textbook). Aspirin is an organic acid, white crystal, insoluble in water, with salicylic acid as a raw material
6. Penicillin is an important antibiotic, that is, an anti-inflammatory drug, which has the excellent function of preventing the growth of a variety of bacteria, and a skin sensitivity test (referred to as a "skin test") should be carried out before use to prevent the occurrence of allergic reactions
7. The antacid effect is to neutralize stomach acid and relieve stomach discomfort, and its main ingredient is to neutralize chemicals that can neutralize hydrochloric acid, such as aluminum hydroxide, sodium bicarbonate, magnesium carbonate, magnesium hydroxide, calcium carbonate, etc
8, natural medicine ephedrine has the effect of cough and asthma, but taking ephedrine sometimes appears in the central excitement caused by uneasiness, insomnia, etc., it is best to take sedative hypnotic drugs at night to prevent insomnia, athletes can not take ephedrine