1. Notes on Two Required Knowledge Points of Biology in Senior Two (I)
1. Succession: The process in which one community is replaced by another over time. Rock stage → lichen stage → moss stage → herb stage → shrub stage → forest stage.
(1) Primary succession: refers to the succession that occurs on the ground that has never been covered by plants or where there was vegetation but it was completely eliminated.
(2) Secondary succession: refers to the succession in which the primary vegetation no longer exists, but the primary soil conditions are basically preserved, even the seeds or other propagators of plants are preserved.
2. Measurement methods of population density: sampling method (animals and plants with weak athletic ability) and marking recapture method (animals with strong athletic ability).
3. Population: the general name of all individuals of the same species in a certain area.
Community: the collection of all biological populations gathered in an area at the same time.
Ecosystem: all living and inorganic environments in a certain area. Ecosystem on Earth: Biosphere
4. Population change curve;
(1) "j" growth curve conditions: adequate food and space conditions, suitable climate, no one can hurt.
(2) "S" growth curve condition: limited resources and space.
5.k value (environmental carrying capacity): the number of population that can be maintained in a certain space without destroying environmental conditions. Choose fishery resources at K/2, and kill pests before K/2 (reduce environmental carrying capacity).
6. Abundance: the number of species in the community.
2. Notes on the Compulsory Knowledge of Biology in Senior Two
Stability of ecosystem 1. Concept: the ability of an ecosystem to maintain or restore its relatively stable structure and function.
2. The reason why the ecosystem can remain relatively stable is because it has the ability of self-regulation. Self-regulation ability of ecosystem. The foundation is negative feedback. The more kinds, the more complex the nutritional structure and the greater the self-regulation ability;
3. The stability of ecosystem is relative. When large-scale interference or external pressure exceeds the self-renewal and self-adjustment ability of ecosystem, it may lead to the destruction of ecosystem stability and even the collapse of the system.
4. Stability of biological system: including resistance stability and resilience stability.
The simpler the composition and structure of the ecosystem, the lower the stability of resistance, and vice versa. Grassland ecosystem has strong resilience and stability, and can be restored after grassland destruction. Forest restoration is very difficult. An ecosystem with strong resistance and stability has weak resilience. Note: Ecosystem has the ability of self-regulation. But there are certain restrictions. Maintain its stability and make people and nature develop harmoniously.
5. Measures to improve the stability of the ecosystem: Proper planting of shelterbelts on the grassland can effectively prevent the erosion of sandstorms and improve the stability of the grassland ecosystem. For example, avoiding excessive deforestation and controlling pollutant emissions are effective measures to protect ecosystem stability.
On the one hand, it is necessary to control the degree of interference with the ecosystem, and the utilization of the ecosystem should be moderate, and it should not exceed the self-regulation ability of the ecosystem;
On the other hand, for the ecosystem with high utilization intensity, corresponding material and energy input should be implemented to ensure the coordination of the internal structure and function of the ecosystem.
3. Senior two biology compulsory two knowledge notes three
1, helicase: It acts on hydrogen bonds and is an enzyme that unlocks hydrogen bonds and provides energy by hydrolyzing ATP. They often rely on the existence of single chains and can identify the single chain structure of replication fork. There are many similar helicases in bacteria, all of which have ATPase activity. Most of them move in the direction of 5 ′→ 3 ′, but there are also cases of 3 ′→ 5 ′ movement. For example, in φχ 174, the N ′ protein moves in the direction of 3 ′→ 5 ′ in the process of synthesizing replication form with positive chain as template. Play a role in DNA replication. 2.DNA polymerase: It plays a role in DNA replication. It takes single-stranded DNA as a template, and forms a DNA chain complementary to the template chain through phosphodiester bond, and the formed chain and the mother chain form DNA molecules.
3.DNA ligase: Its function is to form phosphodiester bond between two DNA fragments. If two pieces of DNA cut by the same endonuclease are compared to a ladder broken into two pieces, then DNA ligase can "sew" the broken part of the ladder "handrail" (note: base pairs can be connected by hydrogen bonds instead of connecting base pairs), that is, the gap between the sticky ends of two pieces of DNA. Therefore, it can be used to connect the target gene with the vector in genetic engineering. Unlike DNA polymerase, it does not form phosphodiester bond between a single deoxynucleotide and DNA fragment, but connects two gaps on DNA double strand at the same time, so DNA ligase does not need template.
4.RNA polymerase: also known as RNA replicase and RNA synthetase, its function is to transcribe intact double-stranded DNA as a template while releasing it to form mRNA. After transcription, DNA still maintains double-stranded structure. For eukaryotes, RNA polymerase includes three types: RNA polymerase I transcribes rRNA, RNA polymerase II transcribes mRNA, and RNA polymerase III transcribes small RNA such as tRNA. It plays a role in RNA replication and transcription.
5. Reverse transcriptase: DNA polymerase directed by RNA, which catalyzes the process of synthesizing DNA with RNA as template and deoxynucleotide as raw material. It has three kinds of enzyme activities, namely RNA-directed DNA polymerase, RNase and DNA-directed DNA polymerase. In molecular biology technology, as an important tool enzyme, it is widely used to establish gene banks and obtain target genes. Play a role in genetic engineering.
Restriction endonuclease: Restriction endonuclease mainly exists in microorganisms (bacteria, molds, etc. ). Restriction enzymes can only recognize specific nucleotide sequences and can cut DNA molecules at specific tangents. It is a nuclease ("molecular scalpel") that specifically cleaves phosphodiester bonds in DNA chains. More than 100 species have been isolated from prokaryotes, and almost all prokaryotes contain this enzyme. It is an important tool enzyme for recombinant DNA technology and gene diagnosis. For example, the restriction enzymes found in E.coli can only recognize GAATTC sequence and cleave it between G and A. So far, more than 200 restriction enzymes have been found, and their tangents are different. Insect-resistant genes in Bacillus thuringiensis can be cut off by some restriction enzyme. Play a role in genetic engineering.
7. Cellulase and pectinase: In plant cell engineering, it is necessary to decompose the cell wall of plant cells with cellulase and pectinase in advance to obtain viable protoplasts, and then induce protoplast fusion of different plants.
8. Trypsin: In animal cell culture of animal cell engineering, it is necessary to use trypsin to disperse organs and tissues taken from animal embryos or young animals into single cells, and then prepare cell suspension for culture. Or when used for cell subculture, cells are digested from the bottle wall.
9. Amylase: There are mainly salivary amylase secreted by salivary glands, pancreatic amylase secreted by pancreas and intestinal amylase secreted by intestinal glands, which can catalyze the hydrolysis of starch into maltose.
10, maltase: There are mainly pancreatic maltase secreted by pancreas and intestinal maltase secreted by intestinal gland, which can catalyze the hydrolysis of maltose to glucose.
1 1. Lipase: There are mainly pancreatic lipases secreted by pancreas and intestinal lipases secreted by intestinal glands, which can catalyze the decomposition of fat into fatty acids and glycerol. The bile secreted by the liver emulsifies fat to form fat particles, which is beneficial to fat decomposition.
12, Proteases: Mainly pepsin secreted by gastric glands and trypsin secreted by pancreas, which can catalyze the hydrolysis of protein into polypeptide chains. The result is that the spatial structure of peptide bond and protein is destroyed.
13, peptidase: secreted by intestinal glands, which can catalyze the hydrolysis of polypeptide chains into amino acids.
14, transaminase: the process of catalyzing amino group conversion in protein metabolism. For example, alanine aminotransferase (GPT) in human body can transfer amino groups from glutamic acid to propiolic acid, thus forming alanine and -xx glutaric acid. Alanine aminotransferase (ALT) is the most abundant in the liver, and it is released into the blood when the liver is diseased, so it is often used as an important index to diagnose hepatitis and other diseases in clinic.
15, photosynthetic enzyme: refers to a series of enzymes related to photosynthesis, mainly existing in chloroplasts.
16, respiratory oxidase: a series of enzymes related to cell respiration, mainly existing in cytoplasm matrix and mitochondria.
17, ATP synthase: refers to the enzyme that catalyzes ADP and phosphoric acid and uses energy to form ATP.
18, ATP hydrolase: refers to the enzyme that catalyzes the hydrolysis of ATP to produce ADP and phosphoric acid and releases energy.
19, constitutive enzyme: refers to the enzyme that has always existed in microbial cells. Their synthesis is only controlled by genetic materials, such as enzymes that decompose glucose in Escherichia coli cells.
20. Inducible enzyme: refers to an enzyme that is synthesized only when something exists in the environment, such as an enzyme that decomposes lactose in E.coli cells.
4. Senior two biology compulsory two knowledge notes four
Principle of Photosynthesis 1, Exploration Course of Photosynthesis: Photosynthesis refers to the process that green plants use light energy to convert carbon dioxide and water into organic matter that stores energy and release oxygen.
Plants renew the air.
When plants carry out photosynthesis, they convert light energy into chemical energy and store it.
The products of photosynthesis include starch besides oxygen.
The oxygen released by photosynthesis comes from water. (isotope labeling method)
The way in which carbon in CO2 is converted into carbon in organic matter in photosynthesis is called calvin cycle.
2, the process of photosynthesis:
The total reaction formula is: CO2+H2O→(CH2O)+O2, where (CH2O) stands for saccharide.
According to whether light energy is needed, it can be divided into two stages: bright reaction and dark reaction.
5. Notes on the compulsory knowledge of biology in senior two.
1, the structure of ecosystem includes two aspects: the composition of ecosystem; Food chain and food web. 2. Ecosystem generally includes the following four components: abiotic substances and energy (including sunlight, heat energy, air, water and minerals, etc. ), producers, consumers and decomposers.
3. Producer: autotrophs (mainly refers to green plants and nitrifying bacteria with chemical synthesis).
4. Consumers: including all kinds of animals. Their survival depends directly or indirectly on the organic matter produced by green plants, so they are called consumers. Consumers belong to heterotrophs. Among animals, herbivores who feed directly on plants (also called herbivores) are called primary consumers; Carnivores that feed on herbivores are called secondary consumers; Large carnivores that feed on small carnivores are called tertiary consumers.
5. decomposer: mainly refers to microorganisms such as bacteria and fungi living in saprophytes.
6. Relationship between organisms: There is generally a predatory relationship between different organisms in the food chain; In addition to predation, there is also competition among different species in the food web.
7. The position and function of each component in the ecosystem: abiotic substances and energy are the foundation of the ecosystem, producers are the main components of the ecosystem, consumers are not the necessary components of the ecosystem, and decomposers are the important components of the ecosystem.
8. Difference between consumption level and nutrition level: the consumption level always takes primary consumers as the first level, and the nutrition level takes producers as the first level (producers are the first nutrition level, primary consumers are the second nutrition level, and secondary consumers are the third nutrition level). ); The same organism can be at different nutritional levels and different consumer levels in the food web; The same organism can only have one trophic level and one consumption level in the same food chain, and the difference between them is only one level.
6. Notes on the Compulsory Knowledge of Biology in Senior Two Six
1, the basic unit of protein is amino acid, and the general structural formula of amino acid is NH2-C-COOH. The difference of various amino acids lies in the difference of R groups. 2. Two amino acids dehydrate and condense to form dipeptide, and the chemical bond (—NH—CO—) connecting two amino acid molecules is called peptide bond.
3. During dehydration condensation, the number of water molecules removed = the number of peptide bonds formed = the number of amino acids-the number of peptide chains.
4. The diversity of protein: the variety, quantity and arrangement order of amino acids that make up protein are ever-changing, and the folding ways of polypeptide chains are different.
5. Each amino acid molecule contains at least one amino group (-—NH2) and one carboxyl group (-—COOH), and both amino groups are connected to the same carbon atom, which is also connected to a hydrogen atom and a side chain gene.
6. 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, abbreviated as DNA, and the other is ribonucleic acid, abbreviated as RNA, which is the basic unit nucleotide of nucleic acid.
7, 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.