The first biology note in the eighth grade?

2. Biodiversity: 1) Species diversity; 2) Diversity of living environment; 3) the diversity of sports modes.

3. Fish can live in water, and two characteristics are very important: 1) It can get food by swimming and defend against enemies; 2) Can breathe in water.

4. The structure that fish can overcome resistance in water: streamlined (spindle-shaped) body; The body surface secretes mucus.

When a fish swims, it relies on the left and right swinging of its tail on its trunk to generate the power to move forward. It relies on dorsal fin, pectoral fin, ventral fin and gluteal fin to keep balance, and caudal fin to keep the direction of progress.

6. When it is difficult to do experiments directly with the research object, sometimes experiments are done with the model, that is, imitating the experimental object to do the model, or imitating some conditions of the experiment. Such an experiment is called a simulation experiment.

7. Various fins play an auxiliary and coordinating role in sports.

8. Gills are the respiratory organs of fish.

9. There are abundant capillaries on the gills, so the gills are bright red.

10, gill filaments are many and thin, which is beneficial to full gas exchange in order to expand the contact area with water. Gills do not easily absorb oxygen in the air. After the fish left the water, the gill filaments covered each other, which reduced the contact area with the air and could not get enough oxygen from the air, so they died of lack of oxygen.

1 1, fish gills are very important for breathing in water: gills are bright red and contain rich capillaries; Branchial filaments are many and thin.

12. Water flows in from the fish mouth and out from the rear edge of gill cover.

13. In the water flowing from fish gills, oxygen decreases and carbon dioxide increases.

14, gas exchange: O2-in water-in the capillaries of gill filaments.

Carbon dioxide in gill filament water

15, the main characteristics of fish: there are often scales on the body surface, breathing through gills, swimming through the swing of tail and the coordination of fins.

16, mouth without anus, food enters the digestive cavity through the mouth, and the digested food residue is still excreted through the mouth. These animals are called coelenterates.

17. Animals with soft bodies and shells are called mollusks.

18. Animals with hard armor are called crustaceans. Crustaceans breathe through gills.

19, coelenterates, mollusks and crustaceans are invertebrates.

20. All kinds of creatures in water are an important part of aquatic ecosystem. They form a close and complicated connection through food chain and food web, and at the same time, they are all influenced by aquatic environment. The change of their species and the increase or decrease of their quantity will affect human life.

2 1. Compared with the water environment, the land environment is much more complicated. 1) is relatively dry; 2) The temperature difference between day and night is large; (3) Insufficient buoyancy in water; (4) gaseous oxygen; (5) The land environment is complex and changeable.

22. Adaptation of animals living on land to the environment: 1) Generally, there are structures to prevent water loss; 2) Not affected by the buoyancy of water, there are generally organs supporting the body and movement, which are used for crawling, walking, jumping, running, crawling and other sports modes to feed and avoid the enemy; 3) Generally, there are various respiratory organs located inside the body that can breathe air, such as trachea and lungs. 4) Generally, there are developed sensory organs and nervous system, which can cope with the changing environment in time.

Annelids are not mollusks, annelids are invertebrates.

24. Animals whose bodies are composed of many similar annular segments are called annelids.

25. Earthworms live in humid soil rich in humus, because they are cold-blooded animals with little temperature change and are suitable for earthworms to live.

26, body segmentation can make the earthworm's body movement flexible.

27. Earthworms rely on muscle contraction and relaxation, bristle support and fixed movement.

28. Earthworms have no special respiratory system. Earthworms' breathing depends on the body wall that can secrete mucus and keep it moist all the time. The earthworm's body wall is densely covered with capillaries, and the oxygen in the air first dissolves in the mucus on the body surface, then penetrates into the body wall and then enters the capillaries on the body wall. Carbon dioxide in the body is also discharged from the body surface through capillaries in the body wall.

29. Earthworms can't keep a constant body temperature and can only live in deep soil with little temperature change.

30. Compared with warm-blooded animals, warm-blooded animals are more adaptable to the environment and are conducive to normal metabolism.

3 1, the rabbit's body temperature is constant, not only by the hair on the body surface, but also by the developed nervous system, circulatory system and respiratory system.

32. Rabbits have long hind limbs, short forelimbs and muscular hind limbs, which are suitable for jumping.

33, front teeth-cut off the canine teeth of food-tear the molars of food-grind food.

34. The structure and position of rabbit's heart and lungs are similar to that of human body, which shows that human and rabbit are very close in classification and belong to mammals.

35. Feeding habits and phytophagy (such as rabbits); Eating meat (such as wolves); Omnivorous (as humans)

36. The cecum is mainly used to digest fiber, and the cecum of herbivores is developed.

37. Rabbit's teeth are divided into incisors and molars. Incisors are suitable for cutting plant fibers, and molars are suitable for grinding food. Rabbits have developed cecum in their digestive tract, which is in line with their habit of eating plants.

38. Rabbits have developed brains, nerves all over the body and developed limbs. They can sensitively perceive changes in the external environment and react quickly.

39. Mammals are the tallest animals, especially vertebrates. There are many kinds, about 4000 on the earth. Except for a few species, they all have the characteristics of body surface coat, viviparous and lactation. Other features: four cavities in the heart, breathing with lungs, constant body temperature, belonging to warm-blooded animals, with incisors, canines and molars.

There are more than 9000 kinds of birds in the world.

4 1, the shape of the bird is streamlined, which reduces the air resistance during flight.

42. Birds' feathers are divided into normal feathers and down feathers (with warm-keeping function). Normal feathers have quills and fan-shaped wings, which can increase the contact area with air and facilitate flight by flapping the air.

43. Birds' pectoral muscles are developed and attached to the keel process, which is conducive to flying in the air.

44. This bird's skeleton is hollow, light and strong, with a prominent sternum and a keel structure, which is convenient for developed pectoral muscles to attach to the sternum (keel), reducing weight and facilitating flight.

45. Digestive characteristics of birds: 1) Large appetite and strong digestive ability, which can meet the digestion of energy during flight; 2) Feces are not stored, which reduces the weight and is beneficial to flying; 3) Short rectum and frequent defecation.

46. Birds have developed hearts and strong working ability, and their blood has strong ability to transport oxygen, which is conducive to flight.

47. Birds have developed airbags (not respiratory organs) to assist lung breathing and meet the demand for oxygen during flight.

48. The whole body of a bird is designed for flight.

49. Mammalian birds among warm-blooded animals

50. Birds are covered with feathers, and their forelimbs become wings, so they have the ability to fly quickly. There is an air bag in the body to assist lung breathing, and the body temperature is high and constant.

5 1. Insects are the most diverse animals, with more than 1 10,000 known species (accounting for 4/5 of the animal species). Insects have three pairs of feet and can crawl. Some insects' feet are specialized into jumping feet, which can jump; Most insects have wings and can fly. Insects are the only flying animals among invertebrates.

52. The wings of insects are different from those of birds in structure, but as far as flying is concerned, they all have these similarities: they are all fan-shaped structures conducive to flying. The operation of these structures is caused by the contraction and relaxation of muscles, which can produce upward lift and forward power in the air. Compared with their bodies, they are light and big, which is conducive to flying in the air.

53. The significance of wings to the life and distribution of insects: it is beneficial to feed, avoid enemies, expand activities and distribution, and find places suitable for mating and spawning.

54. External characteristics of insects: the body of insects is divided into three parts: head, chest and abdomen, and the moving organs-wings and feet are born in the chest. There are well-developed muscles in the chest, which are attached to the exoskeleton, which is a tough shell covering the surface of insects (molting will occur), protecting and supporting the soft organs inside and preventing water evaporation in the body.

55. Insects are classified as arthropods. Besides insects, arthropods include spiders, centipedes, shrimps, crabs and so on. Their similarities are: their bodies are composed of many segments; There is an exoskeleton on the body surface; The foot and antenna are segmented.

56. Larvae live in water, breathe through gills, undergo metamorphosis, then live an amphibious life, breathe through lungs and breathe through skin. This animal is called amphibian.

57. The behavior of animals depends on a certain body structure.

58. The exercise system of mammals consists of bones and muscles (bones, skeletal muscles (exercise muscles) and interosseous joints).

59. The exercise system consists of bones, skeletal muscles and skeletal connections (such as joints).

60. People have 206 bones, skulls, sternum and ribs (immobile); Trunk bone (semi-active)

Bone of limbs (movable); Movable joint (joint)

6 1, people have 26 vertebrae (semi-mobile bone connection)

62. Joint structure: joint head, joint capsule, joint cavity (with synovial fluid to make joint activities flexible), joint fossa and joint cartilage (buffering effect); Joint capsule; Joint head; Joint cavity; Articular cartilage;

sucking disc

63. Joints act as fulcrums in motion and are the points around which bones rotate.

64. The main joints of the human body: upper limbs; Shoulder joint; Lower limbs; Hip joint; Elbow joint; Knee joint; Wrist joint; Ankle; Finger joint; Toe joint.

65. All vertebrates have joints.

66. When exercising, the elbow joint, hip joint, knee joint and ankle joint are easily injured.

67. How to protect joints during exercise: First, make full preparations for exercise before exercise; Second, the intensity of exercise should be appropriate; Third, wear wrist pads and knee pads.

68. The thicker part of skeletal muscle (organ) is called muscle abdomen, and the thinner milky white part at both ends is called tendon.

69. Skeletal muscle has the characteristic of stimulated contraction.

70. Why does skeletal muscle affect bones: When skeletal muscle is stimulated and contracted by nerves, it will affect the movement of bones around joints, so the body will exercise.

7 1, the muscles connected with bones are always coordinated by two groups of muscles.

72. There are more than 600 skeletal muscles in the whole body. When the arm droops naturally, both biceps brachii and triceps brachii relax.

73, elbow flexion, biceps contraction, triceps relaxation; When the elbow is extended, triceps brachii contracts and biceps brachii relaxes.

74. Of course, exercise is not completed only by the exercise system, it needs the control and adjustment of the nervous system and the supply of energy, so it also needs the cooperation of the digestive system, respiratory system and circulatory system.

75. Summarize the role of bones, joints and muscles in exercise in one sentence: skeletal muscle contraction affects the movement of bones around joints, so the body moves.

76. Animals have various behaviors. From the way of acquiring behavior, animal behavior can be roughly divided into two categories. One is the innate behavior of animals, which is determined by the genetic material in animals, which is called congenital behavior; The other is the behavior obtained from life experience and learning through the role of environmental factors on the basis of genetic factors, which is called learning behavior.

77. Many behaviors are the result of the combination of innate behavior and learning behavior, such as bird migration.

78. Innate behavior is the most basic condition for animal survival. Learning behavior enables animals to adapt to the changing environment and survive better.

79. The higher an animal is, the stronger its learning ability and the more it can adapt to the complex environment. Similarly, the more complex the environment, the more behaviors you need to learn.

80. Congenital behavior has great limitations. If a creature has only innate behavior but no learning behavior, then it will be eliminated naturally.

8 1, for a person, skill training and knowledge learning are adapted to the development stage of the brain, and it is difficult to make up once the critical period of learning is missed.

82. Social behavior characteristics: 1. Some organizations often form within groups; 2. Clear division of labor among members; 3. Grades have also been formed in some groups.

83. Groups are arranged in a hierarchical system according to their size, strength, health and ferocity.

84. The "leader" enjoys food and spouse first, and chooses the nesting site first. Other members will obey it, dare not fight back against its attacks, and be responsible for directing the actions of the whole community.

85. Animals' movements, sounds and smells can all play the role of transmitting information.

The significance of social behavior to animal survival: it is often easier to get food and overcome the invasion of natural enemies by relying on the strength of groups, which can effectively ensure the reproduction of species, make groups better adapt to the environment and maintain the lives of individuals and races.

87. In nature, information exchange between living things is ubiquitous (people talk, animals talk). It is precisely because of the existence of material flow, energy flow and information flow that the relationship between organisms is complicated, and "one hair pulls one hair and moves the whole body", and organisms and the environment become a unified whole.

88. There are interdependent and mutually restrictive relationships between the food chain and various organisms in the food web. In an ecosystem, the number and proportion of various organisms are always maintained in a relatively stable state, which 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 material circulation of the ecosystem; 3) Help plants pollinate and spread seeds; 4) Biological control.

90. Biological control refers to the use of organisms to control pests and diseases. In addition to insect control, there are birds and bacteria.

9 1, the role of animals in people's lives: rich in nutrition and available for people to eat; Play a role in medical care; In appreciation and entertainment, literature and art have a certain image; People use it to describe some images or certain characteristics in life; Animals spread some diseases (injuries) to humans.

92. In the ecosystem, the number and proportion of all kinds of organisms are always kept in a relatively stable state.

Now scientists are studying the use of living things (such as animals) as "production workshops" to produce certain substances needed by human beings. This is a bioreactor.

94. Advantages of bioreactor: It can save the cost of building a factory building and purchasing instruments and equipment, and reduce complicated production procedures and environmental pollution.

95. Scientists invent and create various instruments and equipment by carefully observing and studying living things and imitating some structures and functions of living things. This is bionic.

96. The aggregates visible to the naked eye formed by bacteria or fungi are called colonies.

97. Bacterial colonies are relatively small, the surface is smooth and sticky, or the fungal colonies that are rough and dry are generally several times to dozens of times larger than bacterial colonies. The colonies formed by molds are often fluffy, flocculent or cobweb-like, and sometimes they can be red, brown, green and black.

98. Bacteria and fungi, as well as their different species, can be roughly distinguished from the morphology, size and color of colonies.

99. Colonies are often used as an important basis for strain identification.

100. General method for culturing bacteria or fungi: 1) Prepare nutrient base containing nutrients. 2) high-temperature sterilization and cooling of the culture medium. 3) Put a small amount of bacteria or fungi on the culture medium (this process is called inoculation). 4) Petri dishes are cultured in a constant temperature incubator (or a warm place indoors).

10 1. Bacteria and fungi are widely distributed in the biosphere.

102, the survival of bacteria and fungi also needs certain conditions. If you need moisture, suitable temperature, certain living space, organic matter.

103, bacteria and fungi cannot exist in the strict environment of high-temperature mold.

104. Lactic acid bacteria can decompose organic matter into lactic acid only under anaerobic conditions.

105, all bacteria are unicellular organisms.

106, some bacteria are connected in clusters or long chains, but each bacteria also lives independently.

107. Cell structure diagram:

108, the nutritional mode is divided into autotrophic and heterotrophic, the nutritional mode of bacteria and fungi is heterotrophic, and the heterotrophic nutrients are saprophytic and parasitic.

109. In the later stage of growth and development, some bacteria contract, the cell wall thickens and forms spores. Spore is a dormant body of bacteria and has strong resistance to adverse environment. Small and light can also be scattered around with the wind, fall in the right environment, and germinate into bacteria. Bacteria are ubiquitous because of their rapid propagation and spore formation. (Bacteria divide very quickly)

1 10. Yeast is a unicellular fungus. Mould, edible fungi and macrofungi are all multicellular fungi.

1 1 1.

1 12, there is no chloroplast in the cells of fungi, and spore reproduction is carried out.

1 13, the yeast is sprouting.

1 14, Penicillium: spores are turquoise and arranged in a broom shape. The nutritional mode is heterotrophic.

1 15, Aspergillus: spores have many colors and are arranged radially. The nutritional mode is heterotrophic.

1 16, the fungus causing food mildew is mold.

Bacterial fungi

Similarity: there is no chloroplast in the cell, and ready-made organic matter (heterotrophy) is used.

Difference: single cell, no forming nucleus, division and reproduction. There are both unicellular species and multicellular species, and there are real nuclei in cells, most of which are spore reproduction.

1 17, comparing fungi and bacteria:

1 18, the role of bacteria and fungi in nature: (1) participate in the material cycle; (2) Causing animal and plant diseases; (3) Causing animal diseases.

1 19. Most bacteria and fungi are decomposers in the ecosystem.

120. In the material cycle of nature, bacteria and fungi decompose the remains of animals and plants into carbon dioxide, water and inorganic salts, which can be absorbed and utilized by plants to make organic matter. It can be seen that bacteria and fungi play an important role in the circulation of carbon dioxide and other substances in nature.

12 1. Some kinds of bacteria and fungi live parasitically. They absorb nutrients from living animals, plants and people, leading to different diseases for animals, plants and people.

122 and * * * live together, depend on each other and benefit from each other. Once separated, neither of them can live independently. This phenomenon is called * * *. (once separated, you can live independently, called * * * habitat)

123, parasitic (often harmful); * * * Health (mutual benefit).

124, yeast fermentation state:

Organic yeast carbon dioxide+water+energy (more) [mostly used to make bread]

Organic yeast carbon dioxide+alcohol+water+energy (less) [used for brewing]

125, fermentation: anaerobic respiration of microorganisms (also called respiration)

126. Food corruption is mainly caused by bacteria and fungi. These bacteria and fungi can get organic matter from food, and grow and reproduce in food, leading to food decay. Therefore, an important problem of food preservation is preservation. The main principle of preventing food spoilage is to kill or inhibit the growth and reproduction of new army and fungi in food.

127. Some fungi can produce substances that kill some pathogenic bacteria. These substances are called antibiotics.

128, scientists can also use modern technology to transfer some genes from other organisms to some bacteria, and only these bacteria can produce drugs (using bacteria as bioreactors).

129 and 1928, British bacteriologist Fleming invented antibiotics.

130, the significance of biological classification: understanding and protecting biodiversity, making the position of each species in biological classification clear at a glance, and further clarifying the genetic relationship between organisms.

13 1. Biological classification mainly classifies organisms into species, genera and other levels according to their similarity (morphological structure, internal structure and physiological function). The basic unit of classification is species.

132. In angiosperms, flowers, fruits and seeds are often used as important basis for classification.

133, each boundary is divided into six smaller grades, which are: boundary, phylum, class, order, family, genus and species.

134. The more taxonomic units between two organisms, the closer their genetic relationship.

135, outline

136, the higher the classification registration, the greater the difference between Belamcanda lanceolata and Belamcanda lanceolata, the fewer the same features, and the more organisms it contains.

137. The internal form of biodiversity is the diversity of genes, and the external form is the diversity of species.