Biology knowledge in the second volume of the eighth grade 1
Know yourself and improve your health.
The first part evaluates a person's health.
1. Health refers to a good state of physical, psychological and social adaptation.
2. Keep a happy mood: Happiness is the core of teenagers' mental health.
Section 2 Choose a healthy lifestyle
1. Ways to adjust emotions: divert attention; Choose the right way to vent your troubles; self-consolation
2. To explore the effect of alcohol or tobacco extract on the heart rate of Daphnia. 25%) can promote the heart rate of Daphnia, and high concentration of alcohol can inhibit the heart rate of Daphnia.
3. Harm of alcoholism to human health: Alcohol will damage people's heart and blood vessels, and alcoholism will make the brain excessively excited or paralyzed, leading to neurasthenia and mental decline. Long-term alcoholism can lead to alcoholism, excessive drinking and life-threatening.
4. Harm of smoking to human health: When tobacco burns, harmful substances such as nicotine and tar in the smoke enter the human body, causing damage to the human nervous system, reducing people's memory and attention, and also inducing various respiratory diseases, such as chronic bronchitis and lung cancer.
Harm of drugs: it will damage people's nervous system, reduce human immune function, cause cardiopulmonary injury, respiratory paralysis, and even death.
3. In order to prevent mad cow disease from being introduced into China, the China government announced that it would ban the import of beef and dairy products from European countries such as Britain and Holland. From the perspective of preventing infectious diseases, the measures taken by China belong to
A. control the source of infection B. cut off the route of transmission C. protect the susceptible D. plan immunization
4. Someone has a lower limb injury, and dark red blood is slowly flowing from the wound. What is the hemostasis method?
A. Put a band-aid on the wound. B. Stop the bleeding with a tourniquet at the far end.
C, stop bleeding with a tourniquet near the heart d, disinfect the wound, and then wrap it with a sterile emery cloth.
5. Which of the following reactions can prove that artificial respiration is effective?
A. The patient's chest swells slightly with each blow, and the gas can be discharged from the mouth.
B. release the patient's nostril and the gas will be discharged. C. the patient suddenly moves. The patient has a slight pulse.
6. In many developed countries in the world and some developing countries in China, the main diseases that affect human health are
A. Hepatitis B, chronic and non-communicable diseases, genetic diseases and infectious diseases
7. The main cause of alcoholism (drunkenness) is that excessive alcohol paralysis inhibits people.
A. digestive system B. respiratory system C. nervous system D. circulatory system
8. Nowadays, families have a strong sense of anxiety and health care. They are often equipped with small medicine boxes. In addition to the specific drugs of some family members, there are also some commonly used drugs, such as cold granules, fever such as aspirin, stomach cold inflammation such as berberine, and trauma such as mercuric chloride. Commonly used drugs, such as Cheng Yunning, are used for carsickness, and nitroglycerin is commonly used for heart disease patients.
9. The diseases of modern civilization mainly include malignant tumors and cardiovascular and cerebrovascular diseases. Although it is not an infectious disease, it has now become a major disease affecting human health.
1 1. When someone suddenly fainted, which of the following methods is most suitable for emergency help ()
A, take some necessary treatment measures first, and then call "120" to wait for the ambulance.
B, dial "120" first, and take some necessary treatment measures before the ambulance arrives.
C, take some necessary treatment measures first, and then call "1 10" to wait for the ambulance.
D, dial "1 10" first, and take some necessary treatment measures before the ambulance arrives.
12 to explore the effect of tobacco extract on the heart rate of Daphnia;
(1) The research topic is: What effect does tobacco liquid have on the heart rate of Daphnia?
(2) The experimental method is inquiry.
(3) The principle of design is: the principle of control experiment.
(4) If tobacco extract is added to the water containing Daphnia, the heart rate of Daphnia will increase, indicating that tobacco extract has an impact on the life activities of Daphnia. If the tobacco extract is added to the water containing Daphnia, the heart rate of Daphnia will not be affected, indicating that the tobacco extract has no effect on the life activities of Daphnia.
(5) The number of water fleas used in the experiment was 10, and they were divided into two groups, one for the experimental group and the other for the control group.
(6) The method of observing the heart rate of Daphnia is to count with a timer under a microscope to determine the heart rate of Daphnia.
(7) In order to avoid the error of the experiment, we can determine it by repeated calculation with 10 second as the unit of measurement.
(8) The conclusion of the experiment is that alcohol or tobacco extract can promote the heart rate of Daphnia, and the higher the concentration, the stronger the promotion.
13. according to the definition of health by the world health organization, health refers to a good state of physical health and mental health, not just the absence of disease. Happy mood is the core of children's and teenagers' mental health.
14. Drugs are divided into prescription drugs (R) and over-the-counter drugs (OTC) according to whether the prescriptions of professional doctors or professional assistant doctors are needed. No matter what kind of drug it is, before using it, we should carefully understand the main components, indications, usage and dosage, drug specifications, precautions, production date and expiration date of the drug to ensure drug safety.
15, AIDS is an infectious disease that seriously threatens human health. This disease was first discovered in the United States at 198 1, and now it has spread all over the world.
(1) Please talk about the transmission route of AIDS from the link of epidemic disease.
(2) Suppose your classmate or friend is unfortunately infected with HIV, how will you get along with him or her? Why?
16, SARS caused by SARS virus was once prevalent in some parts of China. After the government took a series of correct measures, the disease was effectively controlled. SARS virus causes lung injury of main respiratory organs.
(1) The isolation between SARS patients and suspected SARS patients is the source of infection control in infectious disease prevention measures.
(2) to publicize the knowledge of SARS prevention and control to the masses, and to mobilize the masses to drink traditional Chinese medicine for prevention, which belongs to the protection of susceptible people in preventive measures.
(3) Treat SARS patients with the serum of recovered patients, because the serum contains antibodies against SARS virus. Patients after rehabilitation will not get sick again, which belongs to non-specific immunity.
Effect of alcohol or tobacco extract on heart rate of Daphnia
The assumptions put forward are:
If the tobacco extract is added to the water containing Daphnia, the heart rate of Daphnia will increase, indicating that the tobacco extract has an impact on the life activities of Daphnia. If the tobacco extract is added to the water containing Daphnia, the heart rate of Daphnia will not be affected, indicating that the tobacco extract has no effect on the life activities of Daphnia.
Objective: To explore the influence of alcohol on the heart rate of Daphnia, and to understand the harm of alcoholism to human health.
Materials and instruments: microscope, glass slide, straw, alcohol, measuring cylinder, timer, Daphnia, etc.
Method steps:
(1) Catch Daphnia with a small net in the pond, or buy Daphnia in the flower, bird, fish and insect market.
(2) Suck a Daphnia with a straw and put it on the glass slide, gently cover the glass slide, observe the heartbeat of Daphnia under the microscope and record the speed (times/minute).
(3) Drop different volumes of alcohol (5%, 10%, 15%, 20%) on the glass slide.
Think about it, how to prepare alcohol solutions with different volume fractions?
(4) Observe the influence of alcohol on the rhythm of Daphnia.
Note: Daphnia has a fast heart rate, so be careful when counting.
The eighth grade, the second volume of biological knowledge II
Infectious diseases and immunity
Section 1 Infectious Diseases and Their Prevention
1, pathogen: bacteria, viruses, parasites and other organisms that cause infectious diseases.
2. The basic link of the epidemic of infectious diseases: susceptible people pass through the source of infection.
3. Preventive measures for infectious diseases: control the source of infection, cut off the route of transmission, and protect susceptible people.
Section 2 Immunization and Planned Immunization
1. Three lines of defense of human body:
(1) Line 1: Skin mucosa
(2) The second way: bactericidal substances (lysozyme, which destroys the cell wall of bacteria) and phagocytes in body fluids.
(3) The third way: immune organs (tonsils, lymph nodes, spleen, thymus) and immune cells (lymphocytes).
(4) Nonspecific immunity (one or two lines of defense) Specific immunity (three lines of defense)
2. Antibodies: When pathogens invade the human body and stimulate lymphocytes, lymphocytes will produce a special protein for pathogens.
3. Antigen: a substance (such as a pathogen) that causes the human body to produce antibodies.
4. Immunity: It is a physiological function of the human body, and the human body relies on this function to identify its own and non-self components, thus destroying and repelling the antigenic substances of the human body, or the damaged cells and tumor cells produced by the human body itself, so as to maintain human health.
Vaccine: a biological product usually made of inactivated or attenuated pathogens, which can produce corresponding antibodies after being inoculated into human body.
6. Planned immunization, meaning:
Since the first case of AIDS was discovered in 198 1 USA, more than 200 countries and regions around the world have been seriously threatened by AIDS. At present, the number of HIV-infected people in China has reached 1 10,000. AIDS has become one of the infectious diseases that pose the greatest threat to human health in 2 1 century. Please answer the following questions according to the existing biological knowledge:
(1) AIDS is caused by human immunodeficiency virus (HIV), so HIV is the pathogen of this infectious disease.
(2) The following do not belong to the route of AIDS transmission.
A. blood B. semen C. milk D. handshake
(4) At present, many researchers are developing AIDS vaccines, aiming at making people immune to AIDS, which belongs to nonspecific immunity. The second line of defense to protect the human body refers to bactericidal substances and phagocytes.
(5) In your opinion, how to treat AIDS patients and infected people in daily life?
Care and help them, we should not discriminate against them, but we should pay attention to avoid touching the skin in the process of communication to avoid infection.
In addition to sexual transmission, AIDS will also pass
A. Water transmission B. Handshake transmission C. Blood transfusion transmission D. Air transmission
Example 3. Egg protein was injected into rabbit blood, and rabbit blood was made into serum one week later. If protein is added to the serum, precipitation will occur. Egg protein is equivalent to
A. Antibody B. Antigen C. Pathogen D. External stimulation
During SARS, Zhang's family often used a lot of Chinese herbal medicines to prevent it. As a result, family members have experienced symptoms such as fatigue, joint pain, body aches and diarrhea. What do you think is the most likely reason?
A. type ⅲ allergic reaction caused by Chinese herbal medicine B. immunoglobulin is produced in the body.
C. Improve human immunity and trigger immune response D. Drug poisoning
Example 5. It is () that is both the source of infection and the route of transmission of infectious diseases.
A type B healthy cat and dog use a type C cup used by hepatitis B patients at home, and a type D mosquito carries plasmodium.
Example 6. French scientist Pasteur made a famous experiment with sheep when he was studying anthrax in livestock. The method is shown in the table.
The first time the data packet is processed, the second time the data packet is processed.
The eighth grade, the second volume, biological knowledge 3
organic evolution
The first section, the origin of life on earth.
1. Most scholars believe that the process from inorganic substances in the primitive atmosphere to organic substances and then to primitive life is carried out on the primitive earth, and the cradle of primitive life is the primitive ocean.
2. Primitive earth conditions: high temperature, high pressure, ultraviolet rays, thunder and lightning, primitive ocean and lack of oxygen.
3. protein, nucleic acid is an important substance in life
The course of biological evolution in the second quarter
1. comparison method: according to certain standards, compare interrelated things to determine their similarities and differences.
2. Fossils: the remains, relics or traces of life of organisms buried in the stratum for various reasons and formed after tens of thousands of years of complex changes. For example: archaeopteryx fossils (ancient reptiles → ancient birds)
3. The general trend of biological evolution: simple to complex, low to advanced, aquatic to terrestrial.
4. Fossils are very important evidence for studying biological evolution, and comparative method is the most important method.
5. Fish-amphibians-reptiles-birds-mammals
Algae-bryophytes-ferns-gymnosperms-angiosperms
The reason of biological evolution in the third quarter
1. Simulate the formation process of protective color: the protective color of animals is the result of natural selection.
2. Natural selection: after living competition, the fittest survive and the unsuitable are eliminated.
3. Process: excessive reproduction, survival competition, genetic variation, survival of the fittest.
4. Significance: Organisms constantly evolve through heredity, variation and natural selection.
The problem of ecological origin is still a subject that scientists continue to explore. From 65438 to 0953, American scholar S.L. Miller conducted a simulation experiment, which opened up a new way to study the origin of life through experiments.
The picture on the right shows the device used by American scientist Miller to simulate primitive earth conditions. After vacuumizing the device, the gas is pumped into the glass instrument from A, and then the water at B is boiled, so that the mixed gas flows in the glass tube driven by steam. Then use electrodes to simulate spark discharge in A, and after cooling in B, the molded product is deposited in C ... Please answer the following questions according to the above instructions and pictures:
(1) The function of spark discharge is to simulate lightning.
(2) Miller's question is: Is it possible for the primitive earth to produce life?
(3) He assumed that life might have been born on the primitive earth;
(4) The evidence he collected is that under the experimental conditions, small inorganic molecules generated small organic molecules such as amino acids that did not exist before.
(5) He came to the conclusion that under the primitive earth conditions, small inorganic molecules can breed small organic molecules.
(6) The gas input to the device is mainly methane, ammonia, hydrogen, water vapor, etc.
The eighth grade, the second volume, biological knowledge 4
Inheritance and variation of organisms
Heredity: refers to the similarity between parents and children.
Variation: refers to the difference between offspring and parents.
The first section gene control biological characteristics
1 Biological characteristics: biological morphological and structural characteristics, physiological characteristics and behavior patterns.
2 Relative traits: different manifestations of the same trait of the same organism.
3. Genes control biological characteristics. For example: transgenic super mice and mice.
Organisms inherit genes rather than traits.
Section 2 Gene Transmission from Parents to Children
1. gene: DNA fragment on chromosome that controls biological characteristics.
2.DNA: It is the main genetic material of double helix structure.
3. Chromosome: A substance in the nucleus that can be dyed dark by alkaline dyes.
4. Genes are transmitted through sperm or egg cells. Sperm and egg cells are the "bridge" of gene transmission between parents and children.
5. The morphology and number of chromosomes in each biological cell are determined.
6. Chromosomes exist in pairs in cells of organisms, and genes also exist in pairs, which are located on paired chromosomes respectively.
7. In cell division that forms sperm or egg cells, the number of chromosomes is reduced by half, and only one chromosome exists.
Dominance and Recessiveness of Genes in Section 3
1. Relative traits include dominant traits and recessive traits. The first generation hybrids are dominant.
2. recessive trait genome becomes: dd dominant trait genome is called Dd or DD.
China's marriage law stipulates that marriage is prohibited between lineal blood relatives and collateral blood relatives within three generations.
4. If a family once had genetic diseases or carried pathogenic genes, its descendants are more likely to carry pathogenic genes. If the related offspring remarry and have children, the chances of suffering from this disease will increase.
Aa A a
Ah ah ah ah
AA Aa Aa aa
For example, a class of students conducted a sampling survey on the genetic situation of double eyelids and single eyelids in the population. The statistical results are as follows: Please answer the following questions: (1) From the results of the first group of surveys, it can be inferred that the genes controlling the characteristics of double eyelids are recessive genes.
(2) If the genes controlling dominant traits are represented by A, and the genes controlling recessive traits are represented by A, in the families surveyed in the third group, the gene combination of the mother is aa, and the gene combination of the father is Aa, AA.
(3) If the mother of a family in the second group has double eyelid surgery, the possibility of giving birth to a double-fold eyelid child is 0.
The reason is that this change is influenced by environmental factors, and the genetic material has not changed and will not be passed on to future generations.
(4) Parents have double eyelids and daughters have single eyelids. This phenomenon is called mutation. If the couple has another child, the child's eyelids are double eyelids or single eyelids, and the possibility of single eyelids is 25%.
The fourth quarter of human sex inheritance
1. Each normal human somatic cell has 23 pairs of chromosomes. (Male: 44 Chang +XY Female: 44 Chang+PEP Edition, Volume II, Biology Knowledge Points Summary)
2. Among them, 22 pairs are identical to men and women, which are called autosomes, and 1 pairs are different from men and women, which are called sex chromosomes. The male is XY, and the female is a summary of eighth-grade biology knowledge points in PEP.
3. Equal opportunities for boys and girls, 1: 1.
Example 1. The picture shows the changes of chromosome number during human reproductive development. According to the picture, the answer is:
(1)a and B represent somatic cells of parents respectively, and their chromosome numbers are both 46.
(2)A represents the process in which parents produce germ cells respectively. Germ cells C and D are sperm and egg cells respectively, and their chromosomes are all 23, which is half of that of A and B. ..
(3) Process B is a fertilization process. The formed E cells are called fertilized eggs, and 23 pairs of F cells are daughter's somatic cells with 46 chromosomes. Each pair of chromosomes in somatic cells comes from the father and one from the mother.
Section 5 Biological Variation
1. The variation of biological characters is common. Variation is firstly determined by the difference of genetic material basis, and secondly related to the environment. So there are genetic variation and non-genetic variation.
2. Examples of human applying the principle of genetic variation to cultivate new varieties: artificial selection, cross breeding and space breeding (gene mutation).
Example 1. The correct way to cultivate IVF is
A. In vivo fertilization → embryo transfer → in vitro development B. In vivo fertilization → in vitro development → embryo transfer → maternal development
C in vitro fertilization → in vitro development D in vitro fertilization → in vitro development → embryo transfer → maternal development.
Children look like their parents, because
A. Parents passed on all the genes to their children.
C. Parents passed on some genes to their children respectively. Parents live with their children.
4. There are 30 pairs of chromosomes in bovine somatic cells, so the chromosome numbers of bovine germ cells and fertilized eggs are respectively
A.30, 30 pairs of B.30, 30 pairs of C.30, 30 pairs of D.30, 30 pairs.
5. It is known that double eyelid and single eyelid are a pair of relative traits, in which double eyelid is dominant, denoted by D, single eyelid is recessive, denoted by D .. If a couple has single eyelid, then the probability that their offspring have DD genotype is
a. 100℅b.50℅c.25℅·0℅
6. China scholar Tong Dizhou and others extracted DNA from the visceral cells of salamanders and injected it into the fertilized eggs of goldfish. Therefore, about 65,438+0 ℅ little goldfish have balancers similar to tailed amphibians behind their mouths. This experiment proves that DNA
A. the molecular structure is relatively stable. It can replicate itself. C. it can control traits. It can produce genetic variation.
7. The gene of albinism is recessive gene (H) Xiaoming's parents are normal and Xiaoming is an albino, so the genetic composition of Xiaoming's parents is respectively
A.Hh and hh B.hh and hh C.Hh and Hh D.HH and hh.
8. Among the following variants, those that cannot be inherited are
A. human skin: black, yellow and white B. yellow, white and red corn kernels
C. wheat growing in the shade has thin stems and spikelets.
9. The purpose of prohibiting consanguineous marriage is to
A. prevent the occurrence of genetic diseases B. prevent the spread of genetic diseases
C. reduce the probability of genetic diseases D. reduce the scope of genetic diseases.
10. As shown in the figure, the mice cultivated by transgenic technology are much larger than ordinary mice. Please answer: (6 points).
⑴ In the research of transgenic mice, the character studied is the individual size of mice, and the gene controlling this character is rat growth hormone gene.
In the process of biological reproduction from generation to generation, genes are inherited, not traits.
⑶ The relationship between traits and genes is a gene-determined trait.
The eighth grade, the second volume, biological knowledge 5
Biological reproduction and development
Section 1 Plant Propagation
1. Sexual reproduction: a reproductive mode in which bisexual germ cells combine to form a fertilized egg, and the fertilized egg develops into a new individual.
2. Asexual reproduction: Without the combination of hermaphroditic germ cells, new individuals are directly produced by the mother. Such as cutting, grafting, layering and tissue culture.
3. The key of grafting: the scion is closely combined with the cambium of the rootstock to ensure survival.
4. Inquiry: Treatment of cutting materials
Question: How do materials suitable for cutting need to be treated to survive easily?
Hypothesis: the upper incision of the stem segment is cut horizontally and the lower incision is cut obliquely, which is easy to survive.
Tissue culture: Using the principle of asexual reproduction, it is a high-tech means for plant tissues to rapidly develop into new plants through cell proliferation and differentiation under artificial control.
Section 2 Reproduction and Development of Insects
1. metamorphosis: in the process of developing from fertilized eggs into new individuals, the morphological structure and living habits of larvae and adults are very different, which is called metamorphosis.
2. Complete metamorphosis: the development goes through four stages: egg, larva, pupa and adult. This development is called complete transformation. . For example: silkworms, bees, butterflies, moths, flies and mosquitoes.
3. Incomplete metamorphosis: the development process goes through three stages: egg, nymph and adult. A developmental process like this is called incomplete metamorphosis. Examples: locust, cicada, cricket, mole cricket, mantis.
Section III Reproduction and Development of Amphibians
1. Abnormal development: egg → tadpole → young frog → adult frog.
2. Features: Oviposition, in vitro fertilization.
Section 4 Breeding and Development of Birds
1. process: courtship, mating, nesting, spawning, hatching and brooding.
2. Features: Oviposition and fertilization
3. Structure of bird eggs: yolk is an egg cell. The blastoderm contains the nucleus. Eggshell and eggshell membrane-protection, egg white-nutrition and protection, egg yolk-nutrition. The blastoderm is where the embryo develops.
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