1. When observing a slide specimen with a microscope, Xiao Ming uses a 10× eyepiece and a 20× objective lens, and Xiao Qiang uses a
10× eyepiece and a 45× objective lens. What Xiao Qiang sees differently from Xiao Ming is ( )
A. the brightness of the field of view increases significantly B. the number of cells seen decreases
C. the image of the cells seen becomes smaller D. the field of view is significantly enlarged
2. will be divided into two groups of intact and full seeds A, B, sown at 25 ℃, respectively, group A is planted in fertile and moist soil, group B is planted in barren moist soil, these two groups of seeds, the two groups of seeds in the soil. Soil, the two groups of seeds germination is ( )
A. B first germination B. A first germination C. At the same time germination D. are not germinated
3. in the same plant in the morning, evening, late at night, respectively, to pick the same part of the same three leaves, take the same size of the same piece of the round piece of the perforator, decoloration, treated with iodine, the results are ( )
A. morning picking of the leaf blade B. The leaves picked in the evening are darker blue
C. The leaves picked late at night are darker blue D. The three leaves are the same shade of blue
4. At a certain point in time to determine an organ of the arteries and veins of the flow of blood in the blood of the three substances, the relative value of which is shown in the right figure
The organ is ( )
A. lungs B. brain C. small intestine D. Muscle
5. The following is the combination of oxygen and hemoglobin in the blood of several tissues: tissue A binding rate of 45%, tissue B binding rate of 60%, tissue C binding rate of 75%, tissue D binding rate of 85%, which the most metabolically active is ( )
A. tissue A B. tissue B C. tissue C D. tissue D
6, There are three kinds of digestive fluids A, B, C, they are not gastric fluid and pancreatic fluid, A digestive fluid to promote the C digestive fluid to digest fats, A digestive fluid and B digestive fluid can not digest proteins, while the B digestive fluid and C digestive fluid can digest starch, then, A. B. C these three kinds of digestive fluids are ( )
A. Intestinal fluids, bile, saliva B. saliva, intestinal fluids, bile
C. bile Saliva, intestinal fluid D. Bile, intestinal fluid, saliva
7. When making kimchi, a special altar should be used, and the mouth of the altar must be sealed with water, and the purpose of sealing the mouth of the altar is to ( )
A. isolate the air and inhibit the reproduction of bacteria B. prevent dust and bacteria from entering the altar to prevent contamination
C. create an anoxic environment, which is conducive to lactic fermentation D. prevent the exchange of gases, which is conducive to acetic acid Bacteria respiration
8. A, B, C, D, four people with different blood types, if the B serum check, A, B blood can be agglutinated, by cross-matching test, A can only accept the blood of the C, according to which it is deduced that the blood type of these four people are ( )
A. A, AB, B, O B. B, AB, O, A
C. A, AB, O, B D. AB, A, O, B
9. In 1989, scientists in China successfully introduced the human growth hormone gene into the egg cells of the carp, the development of the carp by such eggs grows significantly faster, the above facts show that ( ）
A. the genes in the cell have obvious obvious recessive B. the genes in the cell are in pairs
C. genes exist on the chromosomes of biological cells D. biological traits are controlled by genes
10. In an emergency, the lizard's tail can automatically break off, and the broken part can do flexion and extension movements, the lizard's behavior is the animal's ( )
A. aggressive behavior B. defensive behavior C. rhythmic behavior D. community behavior
11.
11．Biologists call for the protection of biodiversity, but experiments have proved that many wild animals carry disease-causing organisms, you think we should ( )
A．Hunt down and kill the organisms that carry the bacteria B．Determine to kill them completely and quarantine all of them
C．Implement antibiotics in the animal kingdom D．Determine to protect the non-killing and stay away from close contact
12．The following statements are incorrect about the evolution and ecology of living things.
A．Environmental factors that affect the lives of living things are called ecological factors
B．Weeds in rice fields compete with rice for sunlight, nutrients and water
C．Fertilizers should be applied to crops and vegetables with quick-acting chemical fertilizers and farmyard manure
D．Biology evolves from simple to complex, aquatic to terrestrial, and low to high level
D．Biology evolves from simple to complex, aquatic to terrestrial, and low to high level. The reason for the development of organisms from simple to complex, from aquatic to terrestrial, and from lower to higher is natural selection
13. Tomato seedlings with basically the same growth are cultivated in four pots, A, B, C, and D, with the same conditions except for the different fertilization. After a period of time, tomatoes in which pots the best results ( )
A. phosphorus fertilizer pots B. nitrogen fertilizer pots C. pots pots pots potash D. pots pots without fertilizer
14. Which of the following is a characteristic of pseudomyopia ( )
A. the anterior and posterior diameters of the eyeball become shorter in the retina behind the image
B. lens curvature is too small, refracting ability is too weak
C. eyeballs in which the eyeball is too small, refracting ability is too weak
C. the eyeballs are too small, refracting ability is too weak.
C. The anterior and posterior diameters of the eyeball are too long, and the image falls in front of the retina
D. The eye's regulating structures are overstretched, and the refractive power is too strong
15. The polio vaccine is given to children in the form of sugar pills, and the vaccine and immunity produced by the vaccine are respectively ( )
A. Antigen, specific immunity B. Antibody, specific immunity
C. Antigen, non-specific immunity D. Antibody, non-specific immunity D. Antibody, non-specific immunity
16. carp in the water constantly swallowing water, its main role is ( )
A. filtering food B. regulating the density C. balancing the body D Agree with 0 | Comments 2009-5-23 14:18 № ♀ Soul | Level 1
study process, the textbooks of the various subjects, homework and information regularly together The first thing that you need to do is to get your hands dirty. To be used, a look will know where. And some students access to a particular book, looking around, missing. Time passes in the busy and anxious search. I don't think that unorganized students will learn well.
Comment: The improvement of learning efficiency is largely determined by factors other than learning, which is because many factors such as one's physique, state of mind and condition are closely related to learning efficiency.
Summary
Study must be methodical, and the essential purpose of improving learning methods is to improve learning efficiency.
The level of learning efficiency is a reflection of a student's comprehensive learning ability. In the student age, the learning efficiency is mainly on the academic performance impact. When a person enters the society, he or she has to learn new knowledge and skills in the workplace, and at this time, a person's learning efficiency will affect his (or her) work performance, and then affect his career and future. It can be seen that the development of good study habits and high study efficiency in secondary school is very beneficial to the development of a person's life.
It can be argued that those who are highly efficient in their studies must be students with good academic performance (by implication, good academic performance does not necessarily mean high academic efficiency). Therefore, for most students, improving learning efficiency is the direct way to improve academic performance.
Improving learning efficiency is not an overnight thing, and requires long-term exploration and accumulation. The experience of predecessors can be learned from, but must be fully integrated with their own characteristics. Factors affecting the efficiency of learning, there are within the study, but more factors outside the study. First of all, we must develop good study habits, the rational use of time, but also pay attention to the "concentration, attention, perseverance" and other basic qualities of training, for their own strengths, weaknesses and so on to have a deep understanding. In short, "there is nothing difficult in the world, only fear of the person who has the heart."
Additionally, please pay attention to your biological clock:
Everyone's situation is different, there are some differences, to find out the best time to study, the human brain in a day there are certain activity patterns: generally speaking, 8 a.m. the brain has a rigorous, thorough thinking ability; 3 p.m. the ability to think the most agile; 8 p.m. the strongest memory; the ability to reason in the daytime 12 hours gradually weakened. The reasoning ability is gradually weakened within 12 hours during the day. According to these laws, just get up in the morning, people's imagination is richer, seize the time to capture some inspiration, do some conceptual work, and read the language and recite English words, due to the fresh air in the morning, to participate in some physical exercise; morning to do some rigorous work, listen carefully in class, take good notes; afternoon in addition to listening to the class, to quickly and accurately do a good job of the day's written assignments; night to strengthen the memory and understanding, pre-study homework for the next day. Midday, evening gap time on the arrangement of some effortless transactional work, such as reading the newspaper, collecting writing materials, walk and rest.
Finally, I wish you good health, progress in your studies, all the best and success in your exams!
Occasionally~
I. Multiple Choice Questions
1. The cactus, which grows in the arid zone, has needle-like leaves, which are conducive to its ( )
A. photosynthesis B. lowering of transpiration to keep water in the body
C. respiration to break down substances in the body D. absorption and transportation of water
2. just now. The purpose of drying freshly harvested paddy as soon as possible is to ()
A. enhance respiration B. inhibit respiration
C. promote seed dormancy D. promote seed germination
3. Transplanting a crop with soil is necessary in order to ()
A. ensure that the roots continue to take up organic matter from the soil B. reduce the loss of water from the body
C. protect young and delicate roots
C. protect the roots and the delicate soil from the soil
C. protect the roots and the delicate soil from the soil
C. protect the roots and the soil from the water. Protect young roots and slender root hairs D. Promote normal root respiration
4. Studies have shown that the carbon dioxide content of the atmosphere is gradually increasing, which of the following measures can alleviate this phenomenon ( )
A. Accelerating the development of industrial production B. Planting trees and forests
C. Cutting down trees D. Greatly developing livestock production
5. The water absorbed by the plant which is producing watermelon is mainly used for ( ). A. photosynthesis B. watermelon fruit expansion C. vine growth D. transpiration
6. There are many seeds in a watermelon because there are () in each flower of a watermelon
A. more than one ovary B. more than one stamen C. more than one ovule D. more than one pistil
7. Fertilizing is mainly to provide () for the growth of crops
8.
A. moisture B. inorganic salts C. energy D. organic matter
8 The pistil of a peach blossom consists of which parts ()
A. filaments, styles, and ovary B. stigma, styles, and ovary
C. anthers, filaments, and styles D. filaments, ovaries, and ovules
9. In an experiment in which a green leaf was used to make organic matter in light, a potted geranium was placed in a pot and a green leaf was placed in a pot with a green leaf. the purpose of keeping potted geraniums in the dark for a day and night is to ()
A. deplete the starch in the leaves B. produce a large amount of carbon dioxide C. absorb all the carbon dioxide in the container D.
absorb all the oxygen in the container
10. The inorganic salts that need to be applied in the largest quantities in the cultivation of crops are ().
A. containing iron, zinc and calcium B. containing manganese, molybdenum and copper C. containing nitrogen, phosphorus and calcium D. containing nitrogen, phosphorus and potassium
11. The main reason for plants to grow from small to large is that ()
A. cells grow and cells differentiate B. cells differentiate and vesicles increase C. cells divide and cells grow D. cells divide and vesicles increase
13. The tree planting day in our country is the annual ()
13. The following substances do not need to pass through the stomata to enter the plant body ()
A. water vapor B. oxygen C. carbon dioxide D. inorganic salt
15. . respiration C. transpiration D. all three roles
16. The stems of woody plants are able to thicken because of ()
A. bark B. xylem C. lamina C. phloem D. phloem
17. The ****same ancestor of man and apes is ()
A. chimpanzee B. rhesus macaque C. palaeoparasauroticus D. baboon
18.
18. The site where sperm and egg cells meet and combine to form a fertilized egg is the ()
A. fallopian tube B. uterus C. ovary D. ****
19. Nutrients for the development of the embryo in the mother's uterus come from the ()
A. uterus B. maternal blood C. placenta D. umbilical cord
20. The following groups of substances are both The following groups of substances are both constituent substances of the human body and energy-supplying substances of the human body ()
A. starch, sugar, vitamins B. protein, fat, inorganic salts C. sugar, fat, protein D. protein, water, inorganic salts
21. able to digest the three kinds of organic substances, sugar, protein and fat, digestive juices ()
A. bile B. gastric juice C. intestinal fluids D. saliva
22. The following description of the characteristics of the alveoli is incorrect ()
A. the alveolar wall is a layer of flat epithelial cells
B. the outer surface of the alveoli is surrounded by a wealth of capillaries
C. the number of alveoli is extremely large, and the area of contact with the gases is large
D. the wall of the alveoli has smooth muscle, so the alveoli can expand and contract
23. The structure through which people eat food and inhale air is ()
A. mouth B. pharynx C. larynx D. trachea
24. Which of the following statements may cause food safety accidents ()
A. Fresh fruits should be rinsed with water or peeled and then eaten
B. Packaged food should not be eaten after the shelf life
C. Kitchen and cooking utensils should be kept in a safe place
C .
C. dependence, always need teachers and parents to solve problems in learning and life
D. psychological and mature, sophisticated
2. short answer questions
1. In order to study the relationship between the intensity of light and the intensity of photosynthesis. In the evening, we put goldfish algae in a test tube containing water and placed the test tube successively at different distances from an incandescent lamp to observe the number of bubbles produced in the test tube. The data collected are shown in the table below, please answer the questions after the table according to the data in the table and the knowledge learned:
The distance between the test tube and the lamp (cm)
10
20
30
40
The number of bubbles produced (pcs/min)
60
25
10
5
(1) The relationship between the distance between the plant and the light source and the number of bubbles produced is ____________________________
_______________________________________________.
(2) The composition of the bubbles produced should be _________, which can be tested using the ____________________________
_______________________________________________ method.
(3) If this test tube is placed in a dark environment, the result you predict should be ________________
____________________________________________________.
(4) The conclusion you can draw from the experimental data above is _____________________________________
____________________________________________________.
Eighth Grade Biology Final Review
1. There are about 1.5 million known species of animals, which can be divided into two main groups: vertebrates, which have a spinal column in their bodies, and invertebrates, which do not have a spinal column in their bodies.
2. Diversity of organisms: 1. diversity of species; 2. diversity of living environments; 3. diversity of 00 ways of movement.
3, fish can live in the water, two characteristics are crucial: (1) can rely on swimming old to get food and defense against enemies; (2) can breathe in the water.
4. Fish can overcome resistance in the water structure: streamlined (pike-shaped) body; body surface secretion of mucus.
5. When a fish swims, it relies on its trunk and tail to swing from side to side to generate forward momentum; it relies on its dorsal, pectoral, ventral, and anal fins to maintain balance; and it relies on its caudal fin to keep its forward direction.
6, in the difficult to directly take the object of study to do experiments, sometimes with a model to do experiments, that is, imitation of the object of the experiment to make a model, or imitation of some of the conditions of the experiment to carry out experiments, such experiments are called simulation experiments.
7, a variety of fins in the movement to play an auxiliary role in the coordination.
8. Gills are the respiratory organs of fish.
9. Gills are rich in capillaries and hence they are bright red in color.
10. The gill filaments are numerous and thin in order to enlarge the area in contact with water, which is conducive to adequate gas exchange. Gills are not easy to absorb oxygen in the air, after the fish leave the water, the gill filaments cover each other, reducing the area of contact with the air, can not get enough oxygen from the air, and therefore die of oxygen deprivation.
11, the gills of fish vital to breathing in the water features: gill filaments bright red, containing rich capillaries; gill filaments and more and thin.
12. Water flows in through the mouth of the fish and out through the back edge of the gill cover.
13. The water flowing out of the gills of the fish has less oxygen and more carbon dioxide.
14. Gas exchange O2 in the water - in the capillaries of the gill filaments
Co2 in the gill filaments - in the water
15. The main features of a fish are: the body surface is often scaly, it breathes through the gills, and it swims through the oscillation of the tail and the coordination of the fins.
16, have a mouth without anus, food from the mouth into the digestive cavity, digested food residue is still by the mouth out of the body, these animals are called coelenterates.
17. Animals that rely on shells to protect their soft bodies are called mollusks.
18. Animals with hard nails on their body surface are called crustaceans. Crustaceans breathe through gills.
19. Coelenterates, molluscs and crustaceans are invertebrates.
20, a variety of organisms in the water are an important part of the aquatic ecosystem, through the food chain and food network, forming a close and complex links between them, and at the same time are affected by the aquatic environment, changes in their species and the number of growth and development of the human life will be affected.
21. Compared with the aquatic environment, the terrestrial environment is much more complex. (1) it is drier; (2) there is a big temperature difference between day and night; (3) it lacks buoyancy in water; (4) there is gaseous oxygen; (5) the terrestrial environment is complex and variable.
22, land-living animals adapt to the environment: 1, generally have structures to prevent water loss; 2, not subject to the buoyancy of water, generally have organs to support the body and movement for crawling, walking, jumping, running, climbing and other modes of locomotion in order to forage for food and to avoid the enemy; 2, generally have a variety of respiratory organs capable of breathing in the air and are located inside the body, such as the trachea and lungs; 4. generally have well-developed sensory organs and nervous system, able to respond to the changing environment in time.
23. annelids are not mollusks; annelids are invertebrates.
24. An animal whose body consists of a number of annular segments that resemble each other is called an annelid.
25. Earthworms live in humus-rich, moist soil because they are cold-blooded and the temperature does not vary much for them to live.
26. Body segmentation allows the earthworm's body to move flexibly.
27, earthworms rely on muscle contraction and diastole, bristles support and fixed movement.
28, earthworms do not have a specialized respiratory system, earthworms rely on respiration can secrete mucus, always keep wet body wall to complete. Earthworm body wall is densely covered with capillaries, the oxygen in the air first dissolved in the mucus on the surface of the body, and then seeped into the body wall, and then into the capillaries of the body wall. The carbon dioxide in the body is also discharged from the body surface through the capillaries of the body wall.
29, earthworms can not maintain a constant body temperature, and can only live in the deeper layers of the soil where the temperature does not vary too much.
30. Thermostats are taller and better adapted to their environment than non-thermostats, which facilitates normal metabolism.
31, the rabbit's body temperature is constant, not only by the body surface of the hair, but also need to develop the nervous system, circulatory system, respiratory system *** with the coordination.
32. The rabbit's hind limbs are longer, the forelimbs are shorter, and the hind limbs are muscular and suitable for jumping.
33. Incisors - cut off food Canines - tear food Molars - grind food
34. The structure and parts of the rabbit's heart and lungs are similar to those of the human body. The similarity of the structure and location of the heart and lungs of the rabbit to those of the human body suggests that humans and rabbits are closely categorized as mammals.
35. Diet Phytophagous (e.g., rabbits)
Carnivorous (e.g., wolves)
Omnivorous (e.g., humans)
36. The cecum, which is mainly used for digesting fibers, is well developed in herbivorous animals.
37. The teeth of the rabbit are differentiated into incisors and molars, which are suitable for cutting plant fibers and molars for grinding food. Rabbits have a well-developed cecum on the digestive tract, these are adapted to their plant-eating habits.
38. Rabbits have a well-developed brain and nerves throughout the body, and well-developed limbs, enabling them to sensitively perceive changes in the external environment and quickly respond accordingly.
39, mammals are the highest animals, is a vertebrate, there are many kinds of species, there are about 4000 kinds of the earth, in addition to very few species, have the body surface hairy, foetal, breastfeeding, etc. (other features: four chambers of the heart, breathing with the lungs, a constant body temperature, is a thermostat, teeth have incisors, canines, molars, the differentiation)
40, the world's birds there are There are more than 9000 kinds of birds in the world.
41. The shape of the bird is streamlined to reduce the resistance of the air during flight.
42, the bird's feathers are divided into positive feathers and down feathers (have a warming effect), positive feathers have a feather shaft, the wings are fan-shaped, can increase the area of contact with the air, easy to fan the air and fly.
43. The pectoral muscles of the bird are well developed and attached to the keel, which facilitates flight by fanning the air.
44. The bird's skeleton is hollow, light and strong, with a prominent sternum and keel protrusion, which facilitates the attachment of well-developed pectoral muscles to the sternum (keel protrusion), reduces weight and facilitates flight.
45, birds digestive characteristics: 1, large amount of food, digestive capacity, to meet the flight of energy digestion; 2, feces are not stored, reduce weight, conducive to flight; 3, the rectum is short, frequent defecation.
46. The heart of the bird is well developed and has a strong working capacity, and the blood has a strong ability to transport oxygen, which is favorable for flight.
47. Birds have well-developed air sacs (not respiratory organs) in their bodies, which assist the lungs to breathe and meet the need for oxygen during flight.
48. The whole body of a bird is designed for flight.
49. Thermostats Mammals
Birds
50. Birds have a feather-covered body, forelimbs that turn into wings for the ability to fly quickly, air sacs in the body to assist the lungs in respiration, and a high and constant body temperature.
51, insects are the most diverse class of animals, known species more than 1 million species (accounting for 4/5 of animal species), insects have three pairs of feet, can crawl; some insects foot specialization into jumping feet, can jump; most insects have wings, can fly. Insects are the only invertebrates that can fly.
52, insect wings and bird wing structure is different, but in terms of suitable for flight have these **** the same point: are conducive to the flight of the fan structure, the operation of these structures are caused by the contraction and diastole of the muscles, can be in the air to produce upward lift and forward momentum, relative to the body, are light, the characteristics of the area is large, and is conducive to the fanning of the air and flight.
53, wing on the insect life and distribution of the important significance: help to feed, escape from the enemy, expand the activities and distribution range, help to find a mate, looking for a suitable place to lay eggs.
54, the external characteristics of insects: the insect body is divided into head, thorax, abdomen three parts, the locomotor organs - wings and feet are born in the thorax. The thorax has well-developed muscles attached to the exoskeleton, which is a tough shell covering the surface of the insect's body (moulting occurs) and serves to protect and support the soft internal organs and prevent evaporation of water from the body.
55, insects in the classification of arthropods, arthropods in addition to insects, there are spiders, centipedes, shrimp, crabs, etc., their *** with the same characteristics are: the body consists of a lot of body segments; the body surface has an exoskeleton; foot and antennae divided into sections.
56, juveniles live in the water, breathing with gills, after metamorphosis, and thereafter amphibious life, breathing with lungs, while using the skin to assist respiration, such animals are called amphibians.
57. The behavior of animals depends on certain body structures.
58. The locomotor system of mammals is made up of bones and muscles (bones, skeletal muscles (motor muscles), and connections between bones (such as joints)).
59. The locomotor system is composed of bone, skeletal muscle, and bone connections (such as joints).
60. A human being has 206 bones Skull, sternum, ribs (inactive)
Torso bones (semi-mobile)
Limb bones (mobile) Bone connections (joints) that are mobile
61. A human being has 26 vertebrae (semi-mobile bone connections)
62. Joint structures: joint head, joint capsule, joint cavity (with synovial fluid, which makes the joints are flexible), joint sockets, articular cartilage (cushioning effect).
Joint capsule
Joint head
Joint cavity
Articular cartilage
Articular fossa
63. Joints act as fulcrums in movement and are points around which bone rotates.
64. The main joints of the human body: upper limbs shoulder joints lower limbs hip joints
elbow joints knee joints
wrist joints ankle joints
finger joints toe joints
65. All vertebrates have joints.
66. The elbow, hip, knee and ankle joints are easily injured during sports.
67, how to protect the joints in sports: First, do a good preparation exercise before exercise; second, the intensity of exercise should be appropriate; third, wear wrist and knee pads.
68, skeletal muscle (is the organ) in the middle of the thicker part is called the muscle belly, the two ends of the thinner cream-colored part is called tendon.
69. Skeletal muscle has the property of contracting when stimulated.
70, why the skeletal muscle can pull the bone: when the skeletal muscle is stimulated by the nerve transmission contraction, it will pull the bone around the joint activity, so the body will produce movement.
71. The muscles attached to the bone are always moved by two sets of muscles in conjunction with each other.
72, there are more than six hundred skeletal muscles in the human body, and when the arms are naturally lowered, the biceps and triceps are stretched.
73. When the elbow is flexed, the biceps muscle contracts and the triceps muscle expands; when the elbow is extended, the triceps muscle contracts and the biceps muscle expands.
74, of course, movement is not accomplished by the motor system alone, it requires the control and regulation of the nervous system, it requires the supply of energy, so it also requires the cooperation of the digestive system, respiratory system, circulatory system and other systems.
75, a sentence summarizes the role of bones, joints and muscles in movement: skeletal muscle contraction, pulling the bone around the joints, so the body produces movement.
76, animal behavior is diverse, from the behavior of the way to obtain, animal behavior can be broadly divided into two categories, a class of animals are born, by the genetic material in the animal's body determined by the behavior, known as congenital behavior; the other is in the genetic factors on the basis of the role of the environmental factors, by life experience and learning and obtaining behavior, known as learning behavior.
77. There are many behaviors that are the result of a combination of both innate and learned behaviors, such as the migration of birds.
78, innate behavior is the most basic conditions for the survival of animals, learning behavior so that animals are more adaptable to the changing environment, better survival.
79, the higher the animal, the stronger the learning ability, the more able to adapt to the complex environment. Similarly, the more complex the environment, the more behaviors to learn.
80, innate behavior has great limitations, if a creature only innate behavior without learning behavior, will be eliminated by nature.
81, for a person, the training of skills and the learning of knowledge is compatible with the developmental stage of the brain, once you miss the critical period of learning is difficult to make up.
82, the characteristics of social behavior: 1, groups often form a certain organization within the group; 2, there is a clear division of labor between the members; 3, some groups also form a hierarchy.
83. Hierarchies are formed in groups according to individual size, strength, health and ferocity.
84. The "leader" has priority for food and mates, and for nesting sites, and the other members of the colony make submissive gestures to it, do not dare to fight back against its attacks, and are also responsible for directing the actions of the whole colony.
85. The movements, sounds and smells of animals can all play a role in transmitting information.
86, the significance of social behavior to the survival of animals: rely on the strength of the group is often easier to obtain food and victory over natural enemies, can effectively ensure the reproduction of the species, so that the group better adapted to the environment, to maintain the life of the individual and the race.
87. In nature, the exchange of information among living things is universal (man has a human language and beasts have an animal language). It is because of the existence of material flow, energy flow and information flow, so that the connection between living things is intricate, "pulling one hair and affecting the whole body", living things and the environment to become a unified whole.
88. There is an interdependence and mutual constraint between various organisms in the food chain and food web. In the ecosystem of the number of various organisms and the proportion of always maintained in a relatively stable state, this phenomenon is called ecological balance.
89, the role of animals in nature: 1, animals play an important role in maintaining ecological balance; 2, animals can promote the ecosystem of the material cycle; 3, to help plants pollinate, spread seeds; 4, biological control.
90, biological control is the use of organisms to control pests and diseases. In addition to insect control, there are bird control, fungus control and so on.
91, the role of animals in people's lives: rich in nutrients for people to eat; play a role in medicine and health care; in the ornamental, entertainment, literature and art have a certain image; people in life used to compare some images or some features; animals spread to humans some diseases (harm).
92, in the ecosystem, the number and proportion of various organisms are always maintained in a relatively stable state.
93. Scientists are now studying the use of organisms (such as animals) as "production plants" to produce certain substances needed by human beings, which are called bioreactors.
94. The benefits of bioreactors: they save money on building plants and buying equipment, and they reduce complex production procedures and environmental pollution.
95, scientists through careful observation and study of living things, imitating certain structures and functions of living things to invent and create a variety of instruments and equipment, this is bionic.
96. A bacterium or fungus that multiplies and forms an aggregate visible to the naked eye is called a colony.
97. Bacterial colonies are relatively small, the surface or smooth and sticky, or rough and dry fungal colonies are generally several to dozens of times larger than bacterial colonies. Molds form colonies that are often fluffy, flocculent or cobwebby, and sometimes in different colors such as red, brown, green and black.
98. Bacteria and fungi, and their different species, can be roughly distinguished from each other by the form, size and color of the colonies.
99. Colonies are often used as an important basis for strain identification.
100. Cultivation of bacteria or fungi in general: ① preparation of nutrient-containing nutrient base. ② medium for autoclaving and cooling. (3) a small amount of bacteria or fungi on the medium (this process is called inoculation). ④ Petri dishes are placed in the incubator to maintain a constant temperature (can also be placed in a warm place indoors) for cultivation.