A seventh-grade book

1, the difference between living things and abiotic things includes basic functions such as metabolism, growth, reproduction, heredity and variation.

2. The basic process of scientific inquiry includes asking questions, making assumptions, making plans and implementing plans, and the conclusion is the expression of communication.

3. The main components of microscope eyepiece and objective lens are shadows and mirrors, which can adjust the intensity of light and are used for communication.

4. Use the step microscope: ① the appearance of the optical microscope and (with a low-power lens) ③ observation (when the staring lens at each barrel falls), ④ sorting and storage.

5, visible under the microscope, such as inversion; Magnification of microscope objective and eyepiece. Larger magnification, fewer cells, larger cells and darker vision.

6. If what you see looks like the lower left on the horizon, the slide specimen should be moved to the center, just like moving to the lower left corner. If the sample moves to the upper right corner, look at something, such as moving the bottom to the left.

7, onion leaf epidermal cells temporary patch steps: ① Wipe (wipe cover glass and glass slide) ② Drop (a drop of water) ③ Tear (onion scales have tweezers to tear the leaf epidermis) ④ Display (enlarge a pair to prevent cell overlap) ⑤ Cover (cover glass method: first contact with the side of the glass cover of the water drop, and then gently put it down to prevent the cover glass from bubbling here )⑤U > Dye (dye with iodine).

8. Temporary patch of human oral epithelial cells: ① wipe, ② drip (physiological saline to prevent cell deformation), ③ scrape (scrape off the side wall of oral cavity with toothpick), ④ coat (to prevent overlapping), and ⑤ cover with dye.

9. Except viruses, organisms are all made up of cells. Cell is the basic unit of biological structure and function.

10 has basic structure: plant cell wall, cell membrane, cytoplasm and nucleus, cytoplasmic vacuole, chloroplast and mitochondria. Compared with plant cells, animal cells have no cell walls, chloroplasts and vacuoles.

1 1, the membrane can release controlled substances; There are vacuoles, which contain liquid cells and dissolve various pigments and hot and sour substances. Chloroplast is the place of photosynthesis, mitochondria (animals and plants) are the place of breathing, and they are energy converters.

12, in the process of cell division, it divides first and then resists cracking with high quality. The same number of divisions around the chromosome.

13, cell differentiation and tissue formation. There are basic tissues: animal skin tissue, connective tissue, muscle tissue and nerve tissue. The organizations of plant protection organizations include nutrition organizations, transportation organizations and mechanical organizations.

14, level mammals: cells → tissues → organs → systems → animals.

level

Green flowering plants: cells → tissues → organs → plants.

15. Green plants can be divided into four categories: algae, mosses, ferns and seed plants (including angiosperms and gymnosperms).

16, algae mostly live in water, mostly single-celled individuals and multicellular individuals without roots, stems and leaves, and are the main sources of oxygen on the earth. Common plants are kelp and Spirogyra.

17, the earliest terrestrial plants were bryophytes and ferns, but they lived in wet places.

18, bryophytes have stem-leaf differentiation and no solid roots.

19, pteridophytes have differentiation of roots, stems and leaves, and simple differentiation guiding tissues. Selaginella, a common plant, is full of river red.

20. The roots, stems and leaves of seed plants have developed guiding tissues. When the seeds appear again. The seeds are gymnosperms without peeling. Common plants are ginkgo, pine, cycad and so on. Angiosperms are the highest, such as plants, which have the strongest adaptability and the most varieties.

2 1, the leaf structure includes epidermis, mesophyll and veins. Epidermal cells are transparent and have no chloroplasts. Mesophyll cells have chloroplasts, which are the main places of photosynthesis. There are venous catheters, which can carry water and inorganic salts, and screens to transport organic matter. There are half-moon epidermal guard cells, and the stomata can control the switch, and the stomata are more on the epidermis.

On February 22nd, 95%-99% of the plants lost water through transpiration and absorption.

Transpiration can promote plants to absorb water, and water and inorganic salts can promote transportation and effectively dissipate heat.

Photosynthesis: Green plants use solar energy, carbon dioxide and water to enter, store energy and release oxygen organic chloroplasts.

24. Related matters "Green starch production, reference" experiment: in dark places, the daily use of plants: consumption of starch leaves/u >; . The optical contrast of the control variable is masked from the upper and lower edges. The method of chlorophyll closure is water heating.

25. The test method of oxygen produced by plant photosynthesis is to use vertical wood, and the observed phenomenon is complex wood fuel.

26. The function of sodium bicarbonate is to increase the concentration of carbon dioxide, and the function of sodium hydroxide is to absorb carbon dioxide.

Twenty-seven is to improve the efficiency of interplanting and reasonable close planting in photosynthesis.

28. Breathing: Organic cells are decomposed into carbon dioxide and water with the participation of oxygen, which are released in the process of using energy.

29, photosynthesis day is, breathing day. Photosynthesis is just that chloroplast cells breathe to carry out all living cells.

Timely drainage of intertillage is beneficial to root respiration.

3 1, green is a green energy converter, an automatic air purifier and a natural reservoir.

32. Worms move with the human body through muscles and bristles and breathe with the body wall. The front of the fuselage and the back end of the logo are rings, and the front end near the belt is.

33. The main characteristics of annelids are composed of many similar ring segments.

34, and the most abundant species on earth is arthropod.

35, locust head, chest, abdomen three parts of the body. The surface exoskeleton not only protects and supports the internal structure of the body, but also effectively prevents water evaporation. The antenna is a sensory organ, and the role has touch and smell. The chest has three pairs of feet and two pairs of wings, segmented legs and antennae, and there is a 10-day valve from the chest to the abdomen. The valve body comes from the locust portal.

36, it is a fish spindle, which can reduce the resistance of swimming. Body color is protective color. Finlike organs, mainly from the balance caudal fin, can control the direction of progress. The respiratory organs are gills. A fish whose mouth and gill cover open and close alternately when breathing. It is the flow perception of the direction, energy and determination of the lateral sensory organs.

37. Pigeons with external morphological characteristics suitable for flying (1) include: flying during streamlined body to reduce resistance; Covered with feathers, the forelimbs became wings. The internal structure is characterized by: some thin bones are healed, the long bones are mostly hollow, the keel is developed, and the developed accessories on the chest and wings will affect the completion of flight movements. Toothless mouth, short rectum, feces can not be stored, which is conducive to weight loss.

(2) The flight of birds has adapted to the physical characteristics: double-layer breathing can improve the efficiency of gas exchange; The heart has two atria, two ventricles, two circulation paths and oxygen supply capacity.

38. Double breathing means that every time you breathe, the gas passes through the lungs twice and the gas in the lungs is exchanged twice. Balloons can be temporarily stored without gas exchange. When a bird flies with two breaths.

Pigeon crop can be stored and softened, which is also called "study of stomach pouch" and food is fully digested at first, and finally completely digested in small intestine.

40. The main characteristics of mammals are: body surface coat, teeth differentiated incisors, canines and molars, diaphragm with lungs and body cavities, viviparous lactation and constant body temperature.

4 1, according to whether the vertebrate spine can be divided into vertebrates and invertebrates.

42. Earthworms and body wall breathing, locusts and trachea breathing; Gill and respiration of carp; The breath of frog lung cancer, skin-assisted breathing; The lung breathing of birds is assisted by balloons; Dolphin lung cancer breathing.

43. The body temperature of fish and amphibians is not constant; The constant body temperature of birds and mammals.

44. Animals seek food, avoid natural enemies and reproduce by promoting exercise.

45. The exercise system is composed of the connecting parts of mammalian bones, bones and muscles. Bone and osseointegration are collectively referred to as bone. Bones and skeletal muscles are organs.

46, including bones, muscles, tendons and abdomen. Bones are usually at one or several joints.

47. Joint composition: joint surface, joint capsule and joint cavity. Articular cartilage surface, synovium in joints, flexible combination. Joint capsule ligament of United company.

48. When the excitability of skeletal muscle nerve is stimulated, it will contract, thus affecting the joint activity of bone and producing exercise. When one elbow, biceps brachii contracts and triceps brachii relaxes; When the elbow and triceps brachii contract, biceps brachii relaxes.

49. According to animal behavior, animal behavior can be divided into innate behavior and learning behavior. Congenital behavior is determined by genetic factors, and acquired behavior is gradually manifested.

50. Social behavior with animals is a kind of camp group life, which is characterized by obvious internal organization, clear division of labor among members and clear hierarchical structure.

5 1, animals help plants pollinate and spread seeds, which is beneficial to expand the distribution of plants; Promote the material circulation of the ecosystem.

52, bioreactor refers to the use of transgenic technology, genetic transformation of animals, so that they can produce drugs for human use or meet nutritional needs. As for the organic waste treatment of "insect bioreactor", it can be; "Mammary gland bioreactor" can hold human lactoferrin agricultural products milk. Aircraft and radar invented by bionics simulate computers and robots developed by human brains.

53. Virus-free is an organism with a cellular structure, which consists of genetic material and the inner shell of protein. The parasitic way of nutrition in living cells is self-replication. Animal virus, plant virus and bacterial virus (phage) can be separated.

54. Bacteria are the most abundant and widely distributed microorganisms in the biosphere. They are unicellular, forming non-saprophytic or parasitic nuclear cells in a nutritional way, and their reproduction mode is division and reproduction. In unfavorable environment, Bacillus will be formed, which is a dormant bacterial body.

55. Single-celled fungi exist, such as yeast, and many cells, such as bacteria and mold mushrooms. Its nutrition is saprophytic and parasitic. With the reappearance of spores.

56. Taxonomic unit boundaries, phyla, class, order, family, genus and species. The largest is the community, and so is the smallest. A larger taxon contains more species and less than * * * with the same characteristics.

57, depending on whether plant seeds propagate into plants and plant spores; According to whether the seed packaging bags of seed plants are gymnosperms and angiosperms and the number of seed cotyledons, angiosperms can be divided into dicotyledonous plants and monocotyledonous plants. next year

Seven books

58. The six major nutrients include carbohydrate food, fat, protein, inorganic salts, water and vitamins. Dietary fiber is called the seventh nutrient.

59. The most important carbohydrate of human energy substance is cellular protein, and the energy reserve substance is fat. Cells that do not constitute or provide energy are vitamins. The main substance of cells is water.

60. Suffering from night blindness due to lack of vitamins and carrots in the liver; Lack of vitamin C, gum bleeding and pain, scurvy, supplement fruits and vegetables; Lack of vitamin D and calcium causes rickets and osteoporosis, and tonifies liver and cod liver oil; Suffering from beriberi and angular stomatitis due to lack of vitamin B 1, eating more coarse grains; Patients with iron deficiency anemia; Iodine comes from endemic goiter.

6 1, the digestive system consists of digestive tract and glands. Digestion and oral cavity, stomach and small intestine, stomach, small intestine and colon have absorption functions. Intestine is the main place for digestion and absorption.

62. At the initial stage of oral administration, starch is digested into maltose, and finally glucose is needed; Amino acids digested by stomach protein in small intestine are digested; Fat is digested in the small intestine and begins to produce glycerol and fatty acids.

The liver is the largest gland of bile, and the fat secreted by it has emulsifying effect. Saliva can only digest starch, stomach can only digest protein, and intestine and pancreatic juice can digest carbohydrate, fat and protein.

64. The stomach can absorb a small amount of water, salt and alcohol; The large intestine can absorb water, inorganic salts and vitamins, and there are many annular folds and villi on the inner surface of the small intestine, which greatly increases its digestion and absorption area, and most nutrients are absorbed by the intestine.

65. The respiratory system consists of respiratory tract and lung cancer, of which lung cancer is the main organ. The inhalation of breathing gas plays a role in warming, moistening and cleaning. Dragons are characterized by a large number of alveoli, thin walls and a large number of capillaries outside, which is conducive to the completion of gas exchange.

66. Inhalation, muscle contraction between ribs and diaphragm, chest volume increase, lung expansion, less than >; Ambient air pressure, the air pressure when air enters the lungs

67. The process of breathing includes: gas exchange between lungs and the outside world (through breathing exercises), gas exchange between alveoli (through diffusion), gas transport in blood, and gas exchange in tissues (diffusion).

68. The fundamental measure to control air pollution emissions is afforestation.

69. When blood anticoagulants are added, stratification will occur. The upper layer is plasma, the lower layer is red blood cells, and there are white blood cells and platelets at the junction of the two layers.

70, the main function is to transport nutrients produced by blood cells and main bodies through waste plasma.

7 1, the number of red blood cells is the largest, and the mature red blood cells have no nucleus, which is U >；; Double concave round cake shape. Hemoglobin is protein with iron, which is red. Oxygen is easy to be produced in places with high oxygen content, and oxygen is easy to be precipitated in places with low oxygen content. The function of red blood cells is to transport oxygen.

72. White blood cells are the largest blood cells, and both the nucleus and defense can get sick. Platelets are the smallest blood cells, which are used for bleeding and accelerating blood coagulation.

73. The blood from the heart artery is transported to the blood vessels of the whole body, which are characterized by thick wall, elasticity and fast blood circulation. Bleeding spurts, and the bleeding should stop at the proximal end. Whole body blood is sent back to the veins of the heart. Thin wall, small elasticity, slow blood flow, venous valve of lower limbs, slow bleeding and distal hemostasis: its characteristics. Capillary is the largest and most widely distributed blood vessel, and its function is material exchange. Its characteristics are: thin wall, only one layer of epithelial cells, small cavity, and only one row of red blood cells is allowed to pass when the blood flow is slowest.

74, circulating blood circulation and pulmonary circulation, where the two connect the heart.

75. The heart structure of the myocardium, the walls of the left ventricle and the right ventricle are thicker than the walls. This is because the left ventricle needs blood to be pumped to the whole body and the right ventricle only transports blood to the lungs. Arterial blood flow in left ventricle and left atrium, blood flow in right ventricle and right atrium. Atrioventricular valves are located in the heart and aortic valves to ensure that blood flows from the atrium to the ventricle and from the artery to the ventricle.

Atrial contraction: the atrioventricular valve is opened and the arterial valve is closed; Ventricular contraction: atrioventricular valve closed and aortic valve opened; Diastolic phase: the atrioventricular valve is open and the arterial valve is closed;

76. Path of systemic circulation: Vein capillaries that run through all levels of left ventricle → aorta →→ systemic circulation arteries →→→→→→→→ inferior vena cava and right atrium. The function of the organization is to transport nutrients. When oxygen and waste are taken away, arteries become blood.

Pulmonary circulation route: pulmonary artery and right ventricle →→→→→→ pulmonary capillary pulmonary vein → left atrium. From venous blood to arterial blood.

77. When the bleeding amount reaches 1200- 1500ml, it is life-threatening. You should enter the same blood type, but anyone can enter a small amount of O blood in an emergency. The blood loss is less than 400 ml, and plasma and blood cells can return to normal levels in a short time according to regulations. Therefore, every healthy adult's blood of 200-300 ml will not affect health.

78, arterial pulse refers to pulse, radial artery measurement is consistent with the heart rate; Measurement of brachial artery blood pressure in upper limbs. Blood pressure is higher than 18.7/ 12 kPa hypertension and lower than 12/6.7 kPa hypotension.

79, anemia patients with less red blood cells, iron and some protein or food rich in hemoglobin should be added. The above white blood cell count describes inflammation in some parts of the body.

80. There are three ways for human body to excrete: one is to pass through the lungs in the form of carbon dioxide and a small amount of water in waste gas; Excretion of the second urine in the form of water, salt and urea through the liquid in the urinary system; Thirdly, it exists in water in the form of sweat, inorganic salts and urea through the skin.

8 1 renal cortex, medulla and renal pelvis. Deep cortical color. Cortical inches of glomerular distribution

82. In the kidney, it is composed of more than 654.38+0 million kidneys. The renal corpuscle of each nephron consists of a U-shaped tube and a tubular tube. Renal corpuscles are composed of glomerulus and renal capsule, which are distributed in cortex. Glomerular capillary balls are formed by afferent arterioles, and the renal capsule is double-layered. In the middle of the renal cyst, there is urine communicating with the renal tubule. Renal tubules are distributed in cortex and medulla. There are two capillary nephrons, and the afferent arteriole 1 is an external capillary formed by two efferent arterioles forming glomerular branches. Arterial blood flow from the input artery and the output artery flows through the renal tubules and outside the capillaries.

83. Formation of urine: ① When blood flows through the glomerulus, except protein and other blood cell macromolecules, the plasma part of water is inorganic filtered through the glomerulus to form salts, glucose, urea and other substances in the renal cyst of the original urine; ② The original urine flows through the tubule, all glucose, most water and some inorganic salts are reabsorbed into the blood, and the rest urine is visible.

84, the formation of urine is continuous, and the intermittent discharge of urine is because U >；; The function of bladder for storing urine.

85. Significance of micturition: Waste water discharge and inorganic salts regulate the balance of the body and maintain the normal physiological functions of tissues and cells.

86. The largest organ of the human body is the skin, which consists of epidermis and leather. The stratum corneum and epidermis enter the mucous layer, and there are blood vessels and neurodermis. When the ambient temperature is high, capillaries dilate and sweat glands secrete more. Skin has the functions of protecting, secreting and excreting, regulating body temperature and feeling external stimuli.

87. An endocrine gland secretes hormones directly without catheter, enters gland capillaries, and flows to the whole body with blood. The largest thyroid gland in human beings.

88. Pituitary growth hormone (GH) is the suffering of adolescents secreted by dwarfism with insufficient secretion, ranging from gigantism with excessive secretion to acromegaly with excessive secretion in adults. A painful cretinism, with too much hyperthyroidism and too little secretion in childhood. Diabetic patients with insulin deficiency can take insulin as a course of treatment.

89. The nervous system consists of the central nervous system and the peripheral nervous system (or: brain, spinal cord and nerves). The basic unit of structure and function of nervous system is neuron. Its basic method is neuromodulation reflex. Reflective nerve structure is called reflex arc, including receptor, afferent nerve, nerve center, efferent nerve and effector. After that, the receptor is stimulated to produce nerve impulses.

90. There is a lot of gray matter in the lower part of the spinal nerve center, so it has reflex and white matter conduction functions. The cortex is the highest central regulation of human physiological activities. A special language center of human beings.

89. Unconditional reflex is born by participating in the subsequent completion of the cerebral cortex nerve center. Life, through participation, can complete conditioned reflex in the cerebral cortex. Reflection is the basic way of higher nervous activity. The most prominent feature of human higher nervous activity is the language of air conditioning, which creates the reflection of words. Because of fear.

90, pupil iris size adjustment. Seeing far and near objects clearly is regulated by the curvature of lens and ciliary body. There are photoreceptor cells in the retina, but similar things can stimulate nerve impulses. The form of visual center. Causes of myopia: the convex lens is too large or the eye diameter is too long, just like the light from a distant object will be on the retina side. The method is to wear a corrective concave.

9 1, skin and mucosa form the first line of defense, and body fluids and phagocytic bactericidal substances form the second line of defense. Its functional feature is that it is born there and has a defensive effect on various pathogens, which is called nonspecific immunity.

92. Immune organs and immune cells form a third line of defense to prevent infectious diseases by producing antibodies. Its characteristic is acquired, and it only works on specific pathogens or foreign companies, which is called specific immunity. Antibody is a kind of protein, and the substance that causes the body to produce is called antibody antigen.

93, it has three functions: immune defense, self-stabilization and immune monitoring.

94. Infectious diseases are caused by diseases in organisms in which pathogens can spread. Pathogens include bacteria, viruses, parasites and other organisms. Infectious diseases have epidemic characteristics. Infectious diseases can spread among people, but they must also spread through infected people and susceptible people.

The source of three basic aspects.

95. According to different transmission routes, diseases can be divided into respiratory diseases (transmitted by air and droplets); Gastrointestinal diseases (transmitted by water and food); Blood-borne diseases (transmitted by blood-sucking arthropods); Disease (spread by contact).

96. Measures to prevent infectious diseases can be divided into cutting off transmission routes and protecting vulnerable groups. Bury animal carcasses, isolate the source of infection, vaccinate and protect susceptible people. The rest of these measures are often cut off.

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