The syllabus requires that you can independently complete the biological experiments listed in the biological knowledge table, including understanding the purpose, principle, methods and operation steps of the experiments, mastering relevant operation skills, and comprehensively applying the methods and skills involved in these experiments; Have the ability to verify simple biological facts, and be able to explain, analyze and deal with experimental phenomena and results; Have the ability to explore some biological problems, including using scientific research methods such as observation, experiment and investigation, hypothesis derivation, modeling and system analysis.
Knowledge carding
First, the basic content of biological experiment
(a) the purpose of the experiment (the problem to be solved);
(2) experimental principles (biological knowledge or principles applied to experiments);
(3) experimental methods (commonly used comparative experimental methods);
(four) the indicators to be detected in the experiment (the standard to measure the experimental results);
(5) experimental hypothesis (possible conclusions in the experiment);
(six) experimental equipment (experimental materials, reagents and supplies used in the experiment);
(7) Set up a reasonable control group (common control methods include blank control, self-control, mutual control and conditional control, etc.). );
(eight) experimental operation steps (specific operations in the implementation of the experimental process);
(9) Prediction, recording and analysis of experimental results (result prediction: when the experimental results are not clear, it is generally expected from three aspects, that is, there is no significant difference between the experimental group and the control group, but there is a significant difference between them).
Second, the experimental operation steps [
(1) Generally, it can be divided into three stages.
1, the first stage, experimental preparation. Usually divided into three steps:
(1) Step 1: Group numbering of instrument materials;
(2) Step 2: Preparation of some drugs and pretreatment of materials;
(3) Step 3: Compare the experimental objects in each group (add corresponding materials and reagents, etc. );
2, the second stage, the control of experimental conditions (different conditions in different experiments, such as temperature, O2, light, water, etc. ) [come.
3. In the third stage, observe and record the experimental results. Some physiological experiments need to be repeated.
(b) The experimental operation steps should follow four basic principles.
1, scientific principles-principles and procedures that conform to experiments;
2. Repeatability principle-enable others to complete the experiment according to this step and get the same result through repetition;
3, the principle of simplicity-can use the simplest steps and materials to complete the experiment (economic and easy to get);
4. Univariate principle-eliminate interference and control variables (emphasize the uniqueness of variables)
basic skill
1. Design an experimental scheme to verify that the liquid in the leaf bag of Cordyceps sinensis contains protease but not amylase. It is required to write: experimental principle, experimental method, measurement index (standard for measuring experimental results), applicable materials, drugs and instruments, experimental process and result analysis.
(1) experimental purpose: to verify that the liquid in the leaf sac of cordyceps sinensis contains protease, but not amylase.
(2) Experimental materials: lean meat and potato.
(3) Experimental method: Comparative experimental method.
(4) Principle: The catalysis of enzyme is specific, that is, protease can only promote the decomposition of protein (such as lean meat), but not starch (such as potatoes); Amylase can only promote the decomposition of starch (such as potato pieces), but not protein (such as lean meat pieces).
(5) Measurement index: Volume change of lean meat and potato.
(6) Process (step):
A, preparing 2 pieces of cooked lean meat and 2 pieces of 1cm3 cooked potatoes; 20mL of liquid in the leaf sac of Cordyceps sinensis; 20ml H2O； ; Take 4 pipes with the same number (1, 2, 3, 4);
B, put 1 piece of cooked lean meat into test tubes 1 and 2 respectively, and put 1 piece of cooked potatoes into test tubes 3 and 4 respectively; Inject 10 ml Cordyceps leaf sac liquid into 1 and No.3 test tubes respectively, and inject10ml H2O; Respectively entering test tubes 2 and 4;
C, put the four test tubes at a suitable temperature for a period of time, and observe the volume changes of cooked lean meat and cooked potatoes in each test tube [Hint: only two test tubes can be used, and each test tube is added with 1 cooked lean meat and cooked potatoes (labeled separately), the liquid in Cordyceps leaf sac is added with 1 test tube, and H2O is added with No.2 test tube.
(7) Results and analysis: Only the meat in the test tube 1 became smaller (or disappeared), which proved that the liquid in the Cordyceps leaf bag only contained protease but not amylase.
2. The main ingredient of egg white is protein. In alkaline solution, protein reacts with CuSO4 to produce a purplish red substance, which is the biuret test in protein. According to the characteristics of this reaction, please use the following materials to design an experiment to prove that human salivary amylase is protein.
(1) experimental purpose: to prove that human salivary amylase is protein.
(2) Experimental principle: protein is the main component of human salivary amylase and egg white. In alkaline solution, protein reacts with copper sulfate to produce purplish red substance.
(3) Experimental method: Comparative experimental method.
(4) Index of experimental measurement (standard for measuring experimental results): The biuret test in protein produces purplish red substances.
(5) Materials, drugs and instruments:
① Materials: Egg white and human salivary amylase.
② Drug: biuret reagent (solution A: 0.1g/ml NaOH; ; Solution B: 0.0 1g/mL CuSO4).
③ Instruments: test tube, measuring cylinder and dropper.
(6) Control group setting: Take egg white as the control group.
(7) Operation steps: a, take two identical test tubes and number them; B, adding 2mL of diluted egg white into the test tube 1 and 2mL of fresh human saliva into the test tube 2; C, add 2mLA solution to each of the two test tubes and shake well, then add 3 drops of solution B to each test tube and shake well; Observe and compare the colors of the solutions in the two test tubes.
(8) Results: Both test tubes were purplish red, which proved that human salivary enzyme was protein.
College entrance examination simulation
3. The following is an experiment to explore whether hormone A can cause courtship behavior of castrated adult male mice and its result prediction. Please answer:
(1) A group of castrated adult male mice without courtship behavior were randomly divided into group A and group B. Group A was injected with hormone A solution as the experimental group. Group B was injected with the same amount of normal saline as the control group. The purpose of setting up a control group is to eliminate the interference of normal saline.
(2) Predicting experimental results: If group A shows courtship behavior, but group B does not, it shows that this hormone can cause courtship behavior in ovariectomized mice. If there is no courtship behavior in group A and group B, it means that the hormone cannot cause courtship behavior in ovariectomized mice.