Cell is the basic unit 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 → observing with low-power objective lens → moving the center of 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: C, H, O, N, P, S, K, Ca, Mg.
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. In the fresh weight of living things (such as cactus in the desert), the most abundant compound is water, and the most abundant compound in dry weight is protein.
★ 10 and (1) reducing sugars (glucose, fructose and 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).
rare
★ 1 1, the basic unit of protein is amino acid, and the general formula of amino acid structure is NH2-C-COOH, the region of various amino acids.
H
Don't lie in the difference of R group.
★ 12, two amino acids dehydrate and condense to form dipeptide, and the chemical bond (-NH-CO-) connecting two amino acid molecules is called peptide bond.
★ 13. During dehydration and condensation, the number of water molecules removed = the number of peptide bonds formed = the number of amino acids-the number of peptide chains.
★ 14. The diversity of protein: The types, quantities and arrangement order of amino acids that make up protein are ever-changing, and the folding ways of polypeptide chains are different.
★ 15. Each amino acid molecule contains at least one amino group (-NH2) and one carboxyl group (-COOH), and they are all 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. There are two types of nucleic acids: one is deoxyribonucleic acid, or DNA abbreviation; One 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 (-COOH) of one amino acid molecule is connected with the amino group (-NH2) of another amino acid molecule, and the water of one molecule is removed at the same time, as shown in the figure:
Oh
H2O+NH2-C-C-OH+H-N-C-COOH
R 1 H R2
19、
DNA RNA
★ Full name deoxyribonucleic acid
★ Distribution of nucleus, mitochondria and chloroplast cytoplasm.
Dyed with methyl green skin Luo Hong
Chain number double chain single chain
ATCG base AUCG
Five-carbon sugar deoxyribose
Constituent unit deoxynucleotide
Prokaryotes, eukaryotes, phage 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).
Fat: energy storage; Heat preservation; Buffer area; Reduce pressure
22. Lipid: phospholipid: an important component of biofilm.
cholesterol
Sterol: Sex hormone: promotes the development of human and animal reproductive organs and the formation of germ cells.
Vitamin D: Promote the absorption of calcium and phosphorus in human and animal intestines.
★23. Polysaccharide, protein, nucleic acid, etc. They are all biological macromolecules, and the basic components are monosaccharides, amino acids and nucleotides 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 nutrients and metabolic wastes in the form of water.
Combined water (4.5%)
★25. Most inorganic salts exist in the form of ions. 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 the cell membrane control substances in and out of the cell.
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. Mature mammalian red blood cells are used for cell membrane preparation, 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 is the site of many important chemical reactions.
Separate various organelles to improve the efficiency of life activities.
Nuclear membrane: a double-layer membrane with nuclear pores for mRNA to pass through nucleoli.
structure
33. The nucleus consists of DNA and protein, which are the same substance as chromosomes.
Two States of Chromatin Phase
It is easy to be 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 and benzene.
Auxiliary diffusion: carrier protein assisted, high concentration→ low concentration, such as glucose entering red blood cells.
★36. Transmembrane transport mode actively transports substances: energy is needed; Carrier protein assistance; Low concentration → high concentration, such as inorganic salts and 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 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.
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).
Function: Catalyze and reduce the activation energy required for chemical reaction.
Structural formula: 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、ATP
Mutual transformation with ADP: A-P~P~P A-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 between aerobic respiration and anaerobic respiration
Aerobic respiration and anaerobic respiration
Mitochondrial (main) cytoplasmic matrix
Product carbon dioxide, H2O, energy carbon dioxide, alcohol (or lactic acid), energy.
The reaction formula is c6h 12o6+6o2o6co2+6h2o.
+Energy C6H 12O6 2C3H6O3+ Energy
Energy of C6H 12O6 2C2H5OH+2CO2+
The first stage of the process: 1 molecule glucose is decomposed into 2 molecules of pyruvate and a small amount of [H], and a small amount of energy is released.
Stage 2: Pyruvic acid and water are completely decomposed into CO2.
And [H], releasing a small amount of energy, linear particles.
Bulk matrix
The third stage: [H] combines with O2 to generate water,
A lot of energy, the first stage of mitochondrial inner membrane: aerobic respiration
The second stage: pyruvate is catalyzed in different enzymes.
, broken down into alcohol and carbon dioxide or
Convert into lactic acid
A lot of energy
The main energy source of high-energy phosphate bond of ATP molecule
42, the application of cell respiration:
Bandage the wound and use breathable disinfection gauze to inhibit aerobic respiration of bacteria.
Yeast brewing: ventilation and sealing. Firstly, the fermentation bacteria are allowed to breathe aerobically and multiply in large quantities, and then the anaerobic respiration produces alcohol.
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 chlorophyll b mainly absorbs red light and blue-violet light.
Carotene pigment in chloroplast
Carotenoid lutein mainly absorbs blue-violet light.
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 of 18C, it is considered that plants are only composed of water in soil, regardless of air.
177 1 year, the priestley experiment in Britain confirmed that plant growth can refresh the air, but no light was found.
1779, Ingerhaus of the Netherlands did a lot of experiments, which proved that only under the sunlight, only green leaves can refresh the air.
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 definitely needed.
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 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.
Mitosis: somatic cell proliferation
5 1, meiosis of eukaryotic cell division mode: proliferation of germ cells (sperm, egg cells).
★ amitosis: red blood cells of frogs. Spinning and chromosomes do not change during division.
★52、
Mitosis: DNA molecular replication and protein synthesis are completed, but the number of chromosomes does not increase, and DNA doubles.
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, with a quantitative ratio.
The division period is clear and easy to observe.
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. Differences in mitosis between animal cells and plant cells
Plant cell animal cell
DNA replication is intermittent, protein synthesis (chromosome replication) chromosome replication, centriole also doubled.
In the early stage, spinning occurred at the two poles of the cell, forming a spindle, which was formed by the starlight emitted by the spindle.
At the end of the period, the cell plates formed at the equatorial plate spread around to form cell walls instead of cell plates, and the cells were depressed 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, thus maintaining 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: It 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
Highly differentiated animal nuclei are totipotent, such as cloned sheep.
59, the intracellular water content decreases and the metabolic rate slows down.
Decreased intracellular enzyme activity
Characteristics of cell aging: 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 that cells automatically end their lives, which is 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.
Can proliferate indefinitely.
★6 1, the characteristic morphological structure of cancer cells has changed significantly.
The glycoprotein on the surface of cancer cells is reduced, which is easy to spread and transfer in the body.
62. Cancer prevention and treatment: stay away from carcinogenic factors and conduct ct, nuclear magnetic resonance and oncogene detection; Surgery, chemotherapy and radiotherapy are also acceptable.