Final review of the first volume of biology for eighth grade
1. There are about 1.5 million species of animals known at present. These animals can be divided into two major categories: one is vertebrates, and their There is a spine in the body; the other type is invertebrates, which have no spine in the body.
2. Biological diversity: 1. Diversity of species; 2. Diversity of living environment; 3. Diversity of movement methods.
3. Two characteristics are crucial for fish to live in water: (1) they can obtain food and defend themselves against enemies by swimming; (2) they can breathe in water.
4. The structure that fish can overcome resistance in water: streamlined (spindle-shaped) body; mucus secreted on the body surface.
5. When a fish swims, it relies on the left and right swinging of the trunk and tail to generate forward momentum, maintains balance on the dorsal fin, pectoral fin, pelvic fin, and anal fin, and maintains the forward direction on the tail fin.
6. When it is difficult to directly conduct experiments on research objects, sometimes models are used to conduct experiments, that is, models are made by imitating the experimental objects, or experiments are conducted by imitating certain conditions of the experiment. Such experiments are called simulation experiments.
7. Various fins play a role in assisting coordination during movement.
8. Gills are the respiratory organs of fish.
9. The gills are rich in capillaries, so the gills are bright red.
10. The gill filaments are numerous and thin in order to expand the area in contact with water and facilitate adequate gas exchange. The gills cannot easily absorb oxygen in the air. After the fish leaves the water, the gill filaments cover each other, reducing the contact area with the air. It cannot get enough oxygen from the air, so it dies due to lack of oxygen.
11. The characteristics of fish gills that are crucial for water breathing: the gill filaments are bright red and contain rich capillaries; the gill filaments are numerous and thin.
12. Water flows in from the fish mouth and flows out from the rear edge of the gill cover.
13. In the water flowing out of the fish gills, the oxygen decreases and the carbon dioxide increases.
14. Gas exchange O2 in water - in capillaries of gill filaments
Co2 in gill filaments - in water
15. Main characteristics of fish: body surface They often have scales, breathe through gills, and swim through the coordinated action of tail swings and fins.
16. There is a mouth but no 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 that rely on shells to protect their bodies are called molluscs.
18. Animals with hard armor on their body are called crustaceans. Crustaceans breathe through gills.
19. Coelenterates, molluscs, and crustaceans are all invertebrates.
20. Various organisms in the water are important components of the aquatic ecosystem. They form close and complex connections through food chains and food webs. At the same time, they are all affected by the aquatic environment. Their species Changes and the rise and fall of quantity will affect human life.
21. Compared with the water environment, the land environment is much more complex. (1) Relatively dry; (2) Large temperature difference between day and night; (3) Lack of 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. They generally have structures to prevent water loss; 2. They are not affected by the buoyancy of water and generally have organs to support the body and movement. Crawling, walking, jumping, running, climbing and other forms of movement in order to find food and avoid enemies; 2. Generally have various respiratory organs located inside the body that can breathe in the air, such as trachea and lungs; 4. Universal It has developed sensory organs and nervous system and can respond to changing environments in a timely manner.
23. Annelids are not molluscs, annelids are invertebrates.
24. Animals whose bodies are composed of many ring-shaped segments that are similar to each other are called annelids.
25. Earthworms live in moist soil rich in humus. Because earthworms are cold-blooded animals, the temperature does not change much, which is suitable for earthworms to live.
26. Body segmentation allows earthworms to move flexibly.
27. Earthworms rely on the contraction and relaxation of muscles and the support and fixed movement of setae.
28. Earthworms do not have a specialized respiratory system. Earthworms' breathing depends on their body walls that secrete mucus and remain moist. The body wall of earthworms is densely covered with capillaries. Oxygen in the air first dissolves in the mucus on the body surface, then penetrates into the body wall, and then enters the capillaries in the body wall. Carbon dioxide in the body is also excreted from the body surface through capillaries in the body wall.
29. Earthworms cannot maintain a constant body temperature and can only live in deep soil where the temperature does not change much.
30. Warm-blooded animals are higher-grade than non-warm-blooded animals and are better able to adapt to the environment and are conducive to normal metabolism.
31. The constant body temperature of rabbits depends not only on the hair on the body surface, but also on the coordinated coordination of the developed nervous system, circulatory system and respiratory system.
32. Rabbits have longer hind limbs and shorter forelimbs. The hind limbs are well muscled and suitable for jumping.
33. Incisor teeth - cut off food. Canine teeth - tear food. Molars - grind food.
34. The structure and location of the rabbit's heart and lungs are similar to those of the human body. It shows that the classification of humans and rabbits is very close, and they are both mammals.
35. Food habits Herbivorous (such as rabbits)
Carnivorous (such as wolves)
Omnivorous (such as humans)
36 , The cecum is mainly used for digesting fiber, and the cecum is well developed in herbivorous animals.
37. The teeth of rabbits are divided into incisors and molars. The incisors are suitable for cutting plant fibers, and the molars are suitable for grinding food. Rabbits have well-developed cecum on their digestive tract, which is adapted to their plant-eating habits.
38. Rabbits have developed brains, nerves throughout the body, and well-developed limbs, allowing them to sensitively sense changes in the external environment and respond quickly accordingly.
39. Mammals are the highest animals, vertebrates, and there are many species. There are about 4,000 species on the earth. Except for a few species, they all have the characteristics of body surface hair, viviparity, and lactation. (Other characteristics: four-chambered heart, breathing with lungs, constant body temperature, is a warm-blooded animal, and has teeth that are differentiated into incisors, canines, and molars)
40. There are more than 9,000 species of birds in the world.
41. The bird's shape is streamlined, which reduces air resistance during flight.
42. The feathers of a bird are divided into straight feathers and down feathers (which have the function of keeping warm). The straight feathers have rachis and the wings are fan-shaped, which can increase the area in contact with the air, making it easier to fan the air and fly.
43. The bird's chest muscles are well developed and attached to the keel process, which is helpful for fanning the air and flying.
44. The bones of birds are hollow, light and strong, with a prominent sternum and a keel structure, which allows the developed breast muscles to attach to the sternum (keel process), reducing weight and facilitating flight.
45. Digestive characteristics of birds: 1. Large food intake and strong digestive ability, which can meet the digestion of energy during flight; 2. Feces are not stored, which reduces weight and facilitates flight; 3. Short rectum and frequent defecation.
46. Birds have a well-developed heart, strong working ability, and strong ability of blood to transport oxygen, which is conducive to flight.
47. Birds have well-developed air sacs (not respiratory organs) in their bodies to assist their lungs in breathing and meet their oxygen needs during flight.
48. The whole body of a bird is designed for flight.
49. Warm-blooded animals mammals
Birds
50. The body surface of birds is covered with feathers, and the forelimbs become wings, which enable them to fly quickly. There are air sacs in the body to assist the lungs in breathing, and the body temperature is high and constant.
51. Insects are the most diverse group of animals, with more than 1 million known species (accounting for 4/5 of all animal species). Insects have three pairs of legs and can crawl; some insects have special legs. It turns into jumping legs and can jump; most insects have wings and can fly. Insects are the only flying animals among invertebrates.
52. The structures of insect wings and bird wings are different, but they have the same characteristics in terms of being suitable for flying: they both have fan-shaped structures that are conducive to flight, and the operation of these structures is caused by muscles. Both contraction and relaxation can produce upward lift and forward momentum in the air. Compared with the body, they are both light and large, which is conducive to fanning the air and flying.
53. The importance of wings to the life and distribution of insects: they are helpful for feeding, evading enemies, expanding activity and distribution range, finding mates and mating, and finding suitable places to lay eggs.
54. External characteristics of insects: The body of an insect is divided into three parts: head, thorax, and abdomen. The locomotion organs--wings and feet--are all born in the thorax. The chest has well-developed muscles attached to the exoskeleton. The exoskeleton is a tough shell that covers the surface of the insect's body (molting occurs). It protects and supports the soft internal organs and prevents the evaporation of water in the body.
55. Insects are classified as arthropods. In addition to insects, arthropods also include spiders, centipedes, shrimps, crabs, etc. Their common characteristics are: the body is composed of many body segments; There is an exoskeleton on the body surface; the legs and antennae are segmented.
56. The larvae live in water, breathe with gills, undergo metamorphosis and develop, and then live amphibious life on land and water, breathing with lungs and using skin to assist breathing. Such animals are called amphibians.
57. The behavior of animals depends on certain body structures.
58. The mammalian locomotor system is composed of bones and muscles (bones, skeletal muscles (movement muscles), and the connections between bones (such as joints)).
59. The locomotor system is composed of bones, skeletal muscles and bone connections (such as joints).
60. Humans have 206 bones: skull, sternum, ribs (immobile)
Truncal bones (semi-movable)
Extremity bones (movable) Ability Movable bone connections (joints)
61. Humans have 26 vertebrae (semi-movable bone connections)
62. Joint structures: joint heads, joint capsules, joint cavities (with slip fluid to make joints flexible), glenoid fossa, and articular cartilage (buffering effect).
Joint capsule
Joint head
Joint cavity
Articular cartilage
Glenoid fossa
< p>63. Joints serve as fulcrums in motion and are the points around which bones rotate.64. The main joints of the human body: shoulder joints of the upper limbs, hip joints of the lower limbs
elbow joints, knee joints
wrist joints, ankle joints
finger joints Joint toe joint
65. All vertebrates have joints.
66. During exercise, elbow joints, hip joints, knee joints, and ankle joints are easily injured.
67. How to protect joints during exercise: 1. Be fully prepared before exercising; 2. Exercise intensity should be appropriate; 3. Wear wrist and knee pads.
68. The thicker part in the middle of skeletal muscles (organs) is called the muscle belly, and the thinner milky white parts at both ends are called tendons.
69. Skeletal muscles have the characteristic of contracting when stimulated.
70. Why can skeletal muscles affect bones: When skeletal muscles contract under stimulation from nerves, they will affect bones to move around joints, and the body will move.
71. The muscles connected to the bones are always moved by two groups of muscles in cooperation with each other.
72. There are more than 600 skeletal muscles in the human body. When the arms droop naturally, the biceps and triceps relax.
73. When the elbow is bent, the biceps brachii contracts and the triceps brachii relaxes; when the elbow is extended, the triceps brachii contracts and the biceps brachii relaxes.
74. Of course, exercise is not accomplished solely by the motor system. It requires the control and regulation of the nervous system. It requires the supply of energy, so it also requires the digestive system, respiratory system, circulatory system and other systems. cooperation.
75. One sentence summarizes the role of bones, joints, and muscles in movement: skeletal muscles contract, pulling the bones around the joints, so the body moves.
76. Animal behaviors are diverse. From the perspective of the ways in which behaviors are acquired, animal behaviors can be roughly divided into two categories. One category is that animals are born with it, which is determined by the genetic material in the animal’s body. The determined behavior is called innate behavior; the other type is the behavior that is acquired through life experience and learning on the basis of genetic factors and through the action of environmental factors, which is called learned behavior.
77. There are many behaviors that are the result of a combination of innate behavior and learned behavior, such as the migration of birds.
78. Innate behavior is the most basic condition for animal survival. Learning behavior enables animals to better adapt to changing environments and survive better.
79. The higher the animal, the stronger its learning ability and the better it can adapt to complex environments. Likewise, the more complex the environment, the more behaviors there are to learn.
80. Innate behavior has great limitations. If an organism only has innate behavior but no learned behavior, it will be eliminated naturally.
81. For a person, skill training and knowledge learning are consistent with the developmental stage of the brain. Once the critical period of learning is missed, it is difficult to make up for it.
82. Characteristics of social behavior: 1. A certain organization is often formed within a group; 2. There is a clear division of labor among members; 3. There is also a hierarchy in some groups.
83. The group is arranged into a hierarchy based on individual size, strength, health and ferocity.
84. The “leader” has priority in food and mates, and in choosing nesting sites. Other members will show obedience to it and dare not retaliate against its attacks. It is also responsible for commanding the entire community. action.
85. Animal movements, sounds and smells can all play a role in transmitting information.
86. The significance of social behavior to animal survival: relying on the strength of the group is often easier to obtain food and defeat the invasion of natural enemies, which can effectively ensure the reproduction of species, enable the group to better adapt to the environment, and maintain individuals and races. life.
87. In nature, information exchange between living things is ubiquitous (people have human speech, and animals have animal speech). It is precisely because of the existence of material flow, energy flow and information flow that the connections between living things are intricate, and "one move affects the whole body", so that living things and the environment become a unified whole.
88. There is an interdependent and mutually restrictive relationship between various organisms in the food chain and food web. The number and proportion of various organisms in the ecosystem are 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 material cycle of the ecosystem; 3. Help plants pollinate and spread seeds; 4 , biological control.
90. Biological control is the use of organisms to prevent and control pests and diseases. In addition to using insects to control insect pests, there are also ways to use birds to control insect pests, and to use bacteria to control insect pests.
91. The role of animals in people’s lives: they are rich in nutrients for people to eat; they play a role in medicine and health care; they have a certain image in viewing, entertainment, literature and art; It is used to metaphor some images or certain characteristics in life; animals spread some diseases (harms) to humans.
92. In the ecosystem, the number and proportion of various organisms are always maintained in a relatively stable state.
93. Now scientists are studying the use of living things (such as animals) as "production workshops" to produce certain substances needed by humans. This is a bioreactor.
94. Benefits of bioreactors: It can save the cost of building factories and purchasing instruments and equipment, and can reduce complex production procedures and environmental pollution.
95. Through careful observation and research of living things, scientists imitate certain structures and functions of living things to invent and create various instruments and equipment. This is bionics.
96. The visible aggregate formed by the reproduction of a bacterium or fungus is called a colony.
97. Bacterial colonies are relatively small, and the surface may be smooth and sticky, or rough and dry. Fungal colonies are generally several to dozens of times larger than bacterial colonies. The colonies formed by mold are often fluffy, flocculent or spider web-shaped, and sometimes can appear in different colors such as red, brown, green and black.
98. Bacteria and fungi, as well as their different types, can be roughly distinguished from the shape, size and color of the colonies.
99. Bacterial colonies are often used as an important basis for bacterial species identification.
100. General methods for cultivating bacteria or fungi: ① Prepare a nutrient medium containing nutrients. ②The culture medium is sterilized and cooled at high temperature. ③Put a small amount of bacteria or fungi on the culture medium (this process is called inoculation). ④ Place the petri dish in an incubator maintained at a constant temperature (it can also be placed in a warm place indoors) for cultivation.
101. Bacteria and fungi are organisms widely distributed in the biosphere.
102. Bacteria and fungi also require certain conditions to survive. For example, it needs moisture, suitable temperature, a certain living space, and organic matter.
103. Bacteria and fungi cannot exist in an environment that has been exposed to severe high-temperature mold.
104. Lactic acid bacteria can decompose organic matter into lactic acid only under anaerobic conditions.
105. All bacteria are single-celled organisms.
106. Some bacteria are connected to each other in groups or long chains, but each bacteria also lives independently.
107. Schematic diagram of cell structure:
108. Nutritional methods are divided into autotrophic and heterotrophic. The nutritional methods of bacteria and fungi are heterotrophic. Heterotrophic is further divided into saprophytic and heterotrophic. parasitic.
109. In the later stages of growth and development of some bacteria, they shrink in size, thicken their cell walls, and form spores. Spores are dormant bodies of bacteria and have strong resistance to adverse environments. Small and light, they can be scattered everywhere with the wind, and can germinate into bacteria when placed in a suitable environment. Bacteria's ability to multiply and form spores quickly makes them ubiquitous. (Bacteria divide extremely quickly)
110. Yeast is a single-celled fungus. Molds, edible fungi, and macrofungi are multicellular fungi.
111.
112. Fungi do not have chloroplasts in their cells and reproduce by spores.
113. Yeast reproduces through budding.
114. Penicillium: The spores are green and arranged in a broom shape. The nutritional mode is heterotrophic.
115. Aspergillus: The spores come in various colors and are arranged in a radial pattern. The nutritional mode is heterotrophic.
116. The fungus that causes food to become moldy is mold.
Bacteria Fungi
Phase
Same
Point Cells do not have chloroplasts and use readily available organic matter (heterotrophy).
No
Same as
Single cell, no formed nucleus, reproduction by division. There are both single-celled and multi-celled species, with true nuclei in the cells, and most are spores.
117. Compare fungi and bacteria:
118. The role of bacteria and fungi in nature: (1) Participate in material circulation; (2) Cause diseases in animals and plants (3) ) and animal sex.
119. Most bacteria and fungi are decomposers in ecosystems.
120. In the material cycle in nature, bacteria and fungi decompose the remains of animals and plants into carbon dioxide, water and inorganic salts. These substances can be absorbed and utilized by plants to produce organic matter. It can be seen that bacteria and fungi play an important role in the cycle of carbon dioxide and other substances in nature.
121. Some species of bacteria and fungi live a parasitic life. They absorb nutrients from living animals, plants and humans, causing animals, plants and humans to suffer from different diseases.
122. When two people live together, they are dependent on each other and benefit each other. Once separated, neither can live independently. This phenomenon is called sexual intercourse. (Once separated, they can live independently and are called parasites)
123. Parasitism (often harmful); parasites (mutually beneficial).
124. Yeast fermentation state:
Organic yeast carbon dioxide + water + energy (more) [mostly used for making bread]
Organic yeast carbon dioxide + Alcohol + water + energy (less) [used for winemaking]
125. Fermentation: anaerobic respiration of microorganisms (also called respiration)
126. Food spoilage is mainly Caused by bacteria and fungi, these bacteria and fungi can obtain organic matter from food and grow and multiply in the food, causing food to decay. Therefore, an important issue in food preservation is preservation. The main principle based on preventing food spoilage is to kill new bacteria and fungi in food or inhibit their growth and reproduction.
127. Some fungi can produce substances that kill certain disease-causing bacteria. These substances are called antibiotics (antibiotics).
128. Scientists can also use modern technology to transfer certain genes from other organisms into some bacteria, and only these bacteria can produce drugs (use bacteria as bioreactors).
129. In 1928, British bacteriologist Fleming invented antibiotics.
130. The significance of biological classification: understand the diversity of organisms, protect the diversity of organisms, make the position of each species in biological classification clear at a glance, and also further clarify the genetic relationship between organisms.
131. Biological classification mainly divides organisms into different levels such as species and genus based on their similarity (morphological structure, internal structure, physiological function). The basic unit of classification is species.
132. In angiosperms, flowers, fruits and seeds are often important basis for classification.
133. Each kingdom is divided into six smaller levels, which from largest to smallest are: kingdom, phylum, class, order, family, genus, and species.
134. The more common taxa between two organisms, the closer their genetic relationship is.
135. Class < Subphylum < Phylum
136. The higher the classification registration, the greater the differences between Shegan interior bodies, the fewer the same characteristics, and the number of organisms contained The more.
137. The intrinsic form of biological diversity is the diversity of genes, and the external form is the diversity of species.
138. my country is the country with the richest gymnosperms and is known as the “Hometown of Gymnosperms”.
139. Various characteristics of living things are controlled by genes
140. The destruction of multiple positives in the ecosystem will lead to the loss of biological species diversity and genetic diversity.
141. Under natural conditions, one species of bird becomes extinct every 2000 years on average. On average, one mammal becomes extinct every 8,000 years.
142. The reasons why biodiversity is threatened include (1) change and destruction of living environment; (2) predatory development and utilization; (3) environmental pollution; (4) biological invasion.
143. To protect biological diversity, relevant laws include the Environmental Protection Law, the Marine Environment Protection Law, the Forest Law, the Grassland Law, the Fisheries Law, and the Wildlife Law. Protection Law" and "Soil and Water Conservation Law". (Before each law, "People's Republic of China" must be added)
144. The establishment of nature reserves is divided into: in-situ protection and enclosure protection.
145. Forests are home to 50% to 90% of the world’s terrestrial organisms.
146. Davidia involucrata is an angiosperm. Silver fir is a gymnosperm.