Summary of a compulsory knowledge point of biology in senior high school
1, the structural level of life system is: cell? Organization? Organs? System? Personal? Population? Community? Ecosystem cells are the basic units of organism structure and function; The most basic life system on the earth is the cell.
2. Operating steps of optical microscope: aiming at light? Objective observation at low magnification? Move the center of the field of view (where to move)
? Observe with a high-power objective: ① Only the fine-tuning focus screw can be adjusted; ② Adjust the large aperture and concave mirror.
3. The fundamental difference between prokaryotic cells and eukaryotic cells is that they have a nucleus bounded by a nuclear-free membrane.
(1) Prokaryote: nuclear-free membrane, chromosome-free, such as Escherichia coli and other bacteria, cyanobacteria.
Eukaryotic cells: There are nuclear membranes and chromosomes, such as yeast and various animals.
Note: the virus has no cell structure, but it has DNA or RNA.
4. Cyanobacteria are prokaryotes and autotrophs.
5. The unity of eukaryotic cells and prokaryotic cells is that they both have cell membrane and cytoplasm.
6. The founders of cell theory are Schleiden and Wang Shi. The establishment of cell theory reveals the unity of cells and biological structure. The establishment of cell theory is a process of exploration, inheritance, revision and development in scientific inquiry, which is full of intriguing twists and turns.
7. The types of chemical elements that make up cells (biological world) and inorganic nature are basically the same, but their contents are different.
8. Elements that make up cells
① Macroelements: carbon, hydrogen, oxygen, nitrogen, phosphorus, sulfur, potassium, calcium and magnesium.
② Trace elements: iron, manganese, boron, zinc, molybdenum and copper.
③ Main elements: carbon, hydrogen, oxygen, nitrogen, phosphorus and sulfur.
④ basic element: c
⑤ In the dry weight of cells, C is the most abundant element, and O is the most abundant element in fresh weight.
9. Living things (such as cactus in the desert) are fresh and heavy, with water as the most compound and protein as the most compound in dry matter.
10 and (1) reducing sugars (glucose, fructose, maltose) can react with Feyning reagent to form brick red precipitate; Fat can be dyed orange by Sudan Red No.3 (or red by Sudan Red No.4); Starch (polysaccharide) turns blue when it meets iodine; Protein reacts with biuret reagent to produce purple.
(2) Sugarcane can not be used as the identification material of reducing sugar.
(3) Philin reagent must be used now (unlike biuret reagent, biuret reagent is added with solution A first, and then with solution B).
1 1, the basic unit of protein is amino acid, and the general structural formula of amino acid is NH2? c？ COOH, the difference of amino acids lies in the difference of R groups.
12, two amino acids are dehydrated and condensed to form dipeptide, and a chemical bond (? NH？ CO？ ) is called peptide bond.
13. In dehydration condensation, the number of water molecules removed = the number of peptide bonds formed = the number of amino acids? Number of peptide chains.
14, protein Diversity Reasons: The types, quantities and arrangement order of amino acids that make up protein are ever-changing, and the folding ways of polypeptide chains are also different.
15, each amino acid molecule contains at least one amino group (? NH2) and carboxyl (? COOH), and both have amino groups and carboxyl groups connected to the same carbon atom, which is also connected to a hydrogen atom and a side chain gene.
16, the carrier of genetic information is nucleic acid, which plays an extremely important role in biological genetic variation and protein synthesis. Nucleic acid includes two categories: one is deoxyribonucleic acid, abbreviated as DNA, and the other is ribonucleic acid, abbreviated as RNA, which is the basic unit nucleotide of nucleic acid.
17, protein function:
(1) structural proteins, such as muscle, feather, hair and spider silk.
② catalysis, such as most enzymes.
③ Transport carriers, such as hemoglobin.
④ transmitting information, such as insulin.
⑤ Immune function, such as antibody.
18, the amino acid binding mode is dehydration condensation: the carboxyl group of an amino acid molecule (? COOH) amino group with another amino acid molecule? NH2), while removing a water molecule, as shown in the figure:
Hmm. How interesting
NH2？ c？ c？ Oh +H? n？ c？ COOHH2O+NH2？ c？ c？ n？ c？ Wow!
R 1HR2R 1OHR2
19、DNA、RNA
Full name: deoxyribonucleic acid, ribonucleic acid
Distribution: Nucleus, mitochondria, chloroplasts and cytoplasm.
Dyes: methyl green, piron
Number of chains: double chain, single chain
Base: ATCG, AUCG
Pentose: deoxyribose, ribose
Composition unit: deoxynucleotide, ribonucleotide
Representative organisms: prokaryotes, eukaryotes, phages, HIV, SARS virus.
20. Main energy substance: sugar.
A good energy storage substance in cells: fat
Glycogen: Energy Storage of Human and Animal Cells
Direct energy substance: ATP
2 1, sugar:
① Monosaccharide: glucose, fructose, ribose and deoxyribose.
2 disaccharides: maltose, sucrose and lactose.
③ Polysaccharides: starch and cellulose (plant cells) and glycogen (animal cells).
4 fat: energy storage; Heat preservation; Buffer area; Reduce pressure
22. Lipids: phospholipids (an important component of biofilm)
Cholesterol, sterol (sex hormone: promoting the development of human and animal reproductive organs and the formation of germ cells)
Vitamin D: (promoting the absorption of calcium and phosphorus in human and animal intestines)
23. Polysaccharide, protein, nucleic acid, etc. Are biological macromolecules.
The constituent units are monosaccharide, amino acid and nucleotide in turn.
Biological macromolecules take carbon chain as the basic skeleton, so carbon is the core element of life.
Free water (95.5%): a good solvent; Participate in biochemical reactions; Provide a liquid environment; transport
24. Water exists in the form of nutrients and metabolic wastes.
Combined water (4.5%)
25. Most inorganic salts exist in ionic form. When Ca2+ in mammalian blood is too low, convulsions will occur. Patients with acute enteritis should be supplemented with glucose saline when dehydrated; Workers who sweat a lot at work under high temperature should drink more light salt water.
26. Cell membranes are mainly composed of lipids, protein and a small amount of sugars. Among lipids, phospholipids are the most abundant, and the more complex the cell membrane, the more kinds and quantities of protein. The basic scaffold of cell membrane is phospholipid bilayer; Cell membrane has certain fluidity and selective permeability. Isolate cells from the external environment.
27. The function of cell membrane is to control substances entering and leaving cells and exchange information between cells.
28. The cell wall of plant cells is composed of cellulose and pectin, which has the function of support and protection.
29. The preparation of cell membrane uses mature mammalian red blood cells because there is no nuclear membrane and organelle membrane.
30. Chloroplast: the organelle of photosynthesis; Double coating
Mitochondria: the main place for aerobic respiration; Double coating
Ribosome: the organelle that produces protein; Membraneless
Centrosome: related to animal cell mitosis; Membraneless
Vacuole: It regulates osmotic pressure in plant cells and contains cell fluid.
Endoplasmic reticulum: protein processing
Golgi apparatus: protein is processed and secreted.
Secretory proteins such as 3 1, digestive enzymes and antibodies need four kinds of organelles: ribosome, endoplasmic reticulum, Golgi apparatus and mitochondria.
32. Cell membrane, nuclear membrane, organelle membrane and biofilm system of cells are closely related and coordinated in structure and function.
Maintain a relatively stable intracellular environment, biofilm system function, many important chemical reaction sites to separate various organelles, and improve the efficiency of life activities.
Nuclear membrane: a double-layer membrane with nuclear pores for mRNA to pass through structural nucleoli.
33. The nucleus consists of DNA and protein, which are the same substance as chromosomes. Chromatin in different periods is easily dyed dark by alkaline dyes.
Function: It is the genetic information base and the control center of cell metabolism and heredity.
34. The liquid environment in plant cells mainly refers to the cell fluid in vacuoles.
Protoplast refers to cell membrane, vacuole membrane and cytoplasm between the two membranes.
The protoplasm layer of plant cells is equivalent to a semi-permeable membrane; In plasma-wall separation, plasma refers to the protoplasm layer and the wall is the cell wall.
35. Cell membranes and other biofilms are selectively permeable membranes.
Free diffusion: high concentration? Low concentration, such as H2O, O2, CO2, glycerol, ethanol, benzene.
Auxiliary diffusion: protein auxiliary carrier, high concentration? Low concentrations, such as glucose, enter red blood cells.
36. Transmembrane transport mode actively transports substances: energy is needed; Carrier protein assistance; Low concentration? High concentrations, such as inorganic salts, ions, endocytosis and exocytosis: macromolecules such as carrier proteins.
37. Biofilms such as cell membranes are selectively permeable membranes, allowing water molecules to pass freely, some ions and small molecules can also pass, and other ions, small molecules and macromolecules cannot pass.
38. Essence: Most of the organic substances produced by living cells are protein, and a few are RNA, with high efficiency.
Characteristic specificity: each enzyme can only catalyze one chemical reaction.
The conditions of enzyme action are mild: the enzyme activity is the highest at the appropriate temperature and pH value and the optimal temperature (pH value).
When the temperature and pH value are higher or lower, the activity of the enzyme will be obviously reduced, or even inactivated (too high, too acidic, too alkaline): catalysis will reduce the activation energy required for chemical reactions.
Structural abbreviation: a? P~P~P, a stands for adenosine, p stands for phosphate group, and ~ stands for high-energy phosphate bond.
Full name: adenosine triphosphate
39. mutual transformation between ATP and ADP: a? P~P~PA？ P~P+Pi+ energy
Function: intracellular direct energy substance
40. Cell respiration: The process that organic matter undergoes a series of oxidative decomposition in cells to generate CO2 or other products, release energy and generate ATP.
4 1. Comparison of aerobic respiration and anaerobic respiration: aerobic respiration and anaerobic respiration.
SETTING: Cytoplasmic matrix, mitochondria (main) and cytoplasmic matrix.
Products: carbon dioxide, H2O, energy.
Carbon dioxide, alcohol (or lactic acid), energy
Reaction formula: C6H 12O6+6O26CO2+6H2O+ energy.
C6H 12O62C3H6O3+ energy
C6H 12O62C2H5OH+2CO2+ energy
Process: The first stage: 1 molecule glucose is decomposed into 2 molecules of pyruvate and a small amount of [H], which releases a small amount of energy and cytoplasm matrix.
The second stage: Pyruvate and water are completely decomposed into CO2 and [H], releasing a small amount of energy and mitochondrial matrix.
The third stage: [H] and O2 combine to form water, a lot of energy, mitochondrial inner membrane.
anaerobic respiration
The first stage: aerobic respiration
The second stage: Pyruvate is decomposed into ethanol and CO2 or converted into lactic acid energy under the catalysis of different enzymes.
42. Application of cell respiration: bandage the wound and use breathable disinfection gauze to inhibit aerobic respiration of bacteria.
Yeast brewing: aeration first, then sealing. Firstly, yeast is allowed to breathe aerobically and multiply in large quantities, and then alcohol is produced through anaerobic respiration.
Pots often loosen the soil: promote aerobic respiration at the roots and absorb inorganic salts.
Regular drainage of paddy fields: inhibit the production of alcohol by anaerobic respiration and prevent alcoholism and root rot.
Advocate jogging: prevent strenuous exercise and anaerobic respiration of muscle cells from producing lactic acid.
Tetanus infection wound: the wound must be cleaned in time to prevent anaerobic breathing.
43. The ultimate source of energy needed by living cells is solar energy; The total energy flowing into the ecosystem is the solar energy fixed by the producer.
44.chlorophyll a
Chlorophyll mainly absorbs red light and blue-violet light.
Chlorophyll b (thylakoid membrane) carotene in chloroplasts
Carotenoids mainly absorb blue-purple light.
xanthophyll
45, photosynthesis refers to the green plants through chloroplasts, using light energy, CO2 and H2O into energy storage organic matter, and release the process of O2.
46. In the middle of18c, it was considered that only water in soil was used to build plants, and air was not considered.
177 1 year, the Priestley experiment in Britain confirmed that plant growth can refresh the air, but no light was found.
1779, Ingelhaus, the Netherlands, did many experiments to verify that only green leaves can refresh the air under sunlight, but the composition of the released gas is unknown.
In 1785, it is obvious that O2 is released and CO2 is absorbed.
1845, Meyer, Germany discovered that light energy was converted into chemical energy.
1864, Saks confirmed that besides O2, there is starch as the product of photosynthesis.
1939 Rubin Carmen of the United States used isotope labeling to prove that O2 released by photosynthesis came from water.
47. Conditions: Light is necessary.
Location of photoreaction stage: thylakoid membrane,
Products: [H], oxygen and energy.
Process: (1) Water is decomposed into [H] and O2 under light energy;
(2)ADP+Pi+ light ATP
Conditions: light or no light is ok.
Dark reaction stage position: chloroplast matrix
Products: sugars and other organic compounds and five-carbon compounds.
Process: (1)CO2 fixation: 1 molecule C5 and CO2 generate 2 molecules C3.
(2) Reduction of C3: Under the action of [H] and ATP, part of C3 is reduced to carbohydrate, and part of C3 forms C5.
Connection: There are differences and close connections between the bright reaction stage and the dark reaction stage, which are an indispensable whole. Photoreaction provides [H] and ATP for dark reaction.
48. The concentration of CO2 in the air, the amount of water in the soil, the length and intensity of light, the composition of light and the temperature are all external factors that affect the intensity of photosynthesis: appropriately extending light and increasing the concentration of CO2 can increase the yield.
49. Autotrophic organisms: Inorganic substances such as CO2 and H2O can synthesize organic substances such as glucose, such as green plants and nitrifying bacteria (chemical synthesis).
Heterotrophs: Inorganic substances such as carbon dioxide and H2O cannot synthesize organic substances such as glucose. We can only use the ready-made organic matter in the environment to maintain our life activities, such as many animals.
50. The relationship between cell surface area and volume restricts cell growth, and cell proliferation is the basis of organism growth, development and reproductive inheritance.
5 1, meiosis of eukaryotic cell division mode: proliferation of germ cells (sperm, egg cells).
52. During mitosis: DNA molecular replication and protein synthesis were completed, but the number of chromosomes did not increase, but DNA doubled. Mitosis: somatic cell proliferation
Mitosis: red blood cells of frogs. Spinning and chromosomes do not change during division.
Early stage: the nucleoli of nuclear membrane gradually disappeared, spindle and chromosome appeared, and the chromosome arrangement was disordered.
Mitotic metaphase: Chromosome centromeres are arranged on the equatorial plate, and the chromosome morphology is relatively stable, and the number is clearer and easier to observe than that in metaphase.
Late stage: centromere division, sister chromatid separation, chromosome number doubled.
At the end stage: the nuclear membrane and nucleolus reappear, and the spindle and chromosome gradually disappear.
53. The difference of mitosis between animal cells and plant cells: plant cells and animal cells.
Interphase: DNA replication, protein synthesis (chromosome replication)
Chromosome replication, centriole also doubled.
Early stage: Spinning occurs at the two poles of the cell to form a spindle, and the central body emits star rays to form a spindle.
At the end, the cell plates formed at the equatorial plate spread around to form cell walls.
No cell plate was formed, and the cells were sunken inward from the center and divided into two daughter cells.
54. Characteristics and significance of mitosis: The chromosomes of the mother cell are copied (essentially after DNA replication) and accurately and evenly distributed in the two daughter cells, which maintains the stability of genetic traits between parents and offspring, which is of great significance to biological inheritance.
55, mitosis, chromosome and DNA number changes.
56. Cell differentiation: A process in which the stability of offspring in morphology, structure and physiological functions is different due to the proliferation of one or a type of cells during individual development. It is a permanent change and the foundation of organism development, which makes the cells in multicellular organisms tend to be specialized and is conducive to improving the efficiency of various physiological functions.
57. Examples of cell differentiation: Red blood cells and muscle cells have exactly the same genetic information (the same fertilized egg is formed by mitosis); The failure of morphology and function is due to the different ways in which genetic information is executed in different cells.
58. Cell totipotency means that differentiated cells still have the potential to develop into complete individuals.
Highly differentiated plant cells have totipotency, such as plant tissue culture because cells (nuclei) have this kind of biology.
Genetic information needed for growth and development The nuclei of highly differentiated animals are totipotent, such as cloned sheep.
59, the intracellular water content decreases and the metabolic rate slows down.
Intracellular enzyme activity decreased, and cell aging showed intracellular pigment accumulation.
Intracellular respiration rate decreased and nuclear volume increased.
The permeability of cell membrane decreases, and the transport function of substances decreases.
60. Apoptosis refers to the process in which cells automatically end the life determined by genes. It is a normal natural physiological process, such as the disappearance of tadpole tail. It plays a key role in the normal development of multicellular organisms, maintaining the stability of the internal environment and resisting the interference of external factors, and can proliferate indefinitely.
6 1, the characteristic morphological structure of cancer cells has changed obviously, and the glycoprotein on the surface of cancer cells has decreased, which is easy to spread and transfer in vivo.
62. Cancer prevention and treatment: stay away from carcinogenic factors and conduct ct, nuclear magnetic resonance and oncogene detection; Surgical resection, chemotherapy and radiotherapy can also be performed.