Unit 1: biology and biosphere 1, the same characteristics of biology: 1) Biology needs plant nutrition: most organisms make organic matter through photosynthesis; Animal nutrition: Get ready-made nutrition from outside. 2) living things can breathe. 3) Organisms can excrete wastes from their bodies. The way animals excrete waste: sweating, exhaling and urinating. The way plants excrete waste: fallen leaves. 4) Organisms can respond to external stimuli. Exodus: The zebra quickly fled after discovering the enemy's harm. The response of mimosa to stimulation. 5) Organisms can grow and reproduce. 6) All living things are made up of cells except viruses. 2. Scope of the biosphere: the bottom of the atmosphere, most of the hydrosphere and the surface of the lithosphere. 3. The biosphere provides basic conditions for living things: nutrients, sunlight, air and water, suitable temperature and a certain living space. 4. Environmental factors affecting biological survival: abiotic factors: biological factors such as light, temperature and moisture: other biological factors affecting biological life. Exodus: Ladybug septempunctata preys on aphids, which is a predatory relationship. Weeds and rice in rice fields compete for sunlight, which is a competitive relationship. Division and cooperation of family members of ants and bees. 5. Explore: the influence of light on the life of mouse and girl 1) Ask a question: Will light affect the life of mouse and girl? 2) Make a hypothesis: light will affect the life of a female rat. 3) Make a plan: to test whether the hypothesis is correct, we need to explore it through experiments. The experimental scheme requires that a control experiment needs to be designed, and illumination is the only variable in this inquiry experiment. Other conditions are the same. 4) Implementation plan 5) Conclusion 6) Expression and communication 6. Biological adaptation and influence on the environment: 1) Example of biological adaptation to the environment: Camels in the desert have little urine. The underground roots of Alhagi are much longer than the aboveground parts. Seals in cold seas, thick subcutaneous fat on the chest, flag trees, etc. 2) Biological impact on the environment: Earthworms move in the soil, which can loosen the soil, and their feces increase the fertility of the soil; Sand plants such as windbreak and sand fixation belong to the biological influence environment. 7. Concept and composition of ecosystem: The unified whole formed by organisms and environment in a certain area is called ecosystem. Composition: including biological part and abiotic part. The biological part includes producers, consumers and decomposers. Abiotic parts include sunlight, water, air, temperature, etc. 8. Food chain and food web: The relationship between producers and consumers is mainly the relationship between eating and being eaten, thus forming a food chain. There are often many food chains in an ecosystem, which often cross each other to form a food web. The structure of an organism. Names and functions of various parts of optical microscope: mirror base-stable mirror body. Column—Supports the component above the column. Mirror arm-the part that supports the mirror. Stage-the place where the slide specimen is placed. There is a light hole in the middle and two flat clips on both sides. Lens barrel-the eyepiece is installed at the upper end and the converter is installed at the lower end. Converter-a turntable with an objective lens. Coarse focus screw-when rotating, the lens barrel can be greatly raised and lowered. Fine-tuning the focus screw-when rotating, the lifting range of the lens barrel is small, which can make the image clearer. Eyepiece and objective lens-the eyepiece is the lens for eyes to observe; An objective lens is a lens close to an object. Shader-there are round holes of different sizes on it, called aperture. The light intensity can be adjusted for light holes with different apertures. Reflector-one side is a flat mirror (used in strong light) and the other side is a concave mirror (used in low light). Rotating the reflector can make the light reflect upward through the light hole. The magnification of the object image is the magnification of the eyepiece multiplied by the magnification of the objective lens. 10, observe and load with microscope ① The object seen from the eyepiece is an inverted image. Example: If you see a "D" in the field of vision of a microscope, then "P" is written on transparent paper. (Inverted) ② Eyepiece magnification ╳ objective magnification = microscope magnification 1 1, basic structure and function of cells ① Cell membrane-has the function of protecting the inside of cells, and can also control the entry and exit of substances inside and outside cells. ② Cytoplasm-Cytoplasm contains many fine structures related to various life activities. The cytoplasm of living cells has fluidity, which is beneficial to the material exchange between cells and the external environment. ③ Nucleus-plays an important role in biological inheritance. The nucleus contains a kind of material closely related to biological heredity-genetic material. 12. Difference between plant cells and animal cells: Plant cells have cell walls, chloroplasts and vacuoles in addition to cell membranes, cytoplasm and nuclei like animal cells. 13. Production and observation of onion epidermal cells. Manufacturing steps: (1) First, drop a drop of water in the center of a clean glass slide. (2) Break the onion scales outward, and tear off a small piece of transparent film from the inner surface of the scales with tweezers. (3) Put the torn film into the water drop in the center of the glass slide and flatten it gently with a dissecting needle. (4) Clamp the edge of one side of a cover glass with tweezers, first touch the other side with water drops, then gently flatten it and cover it on the film. Be careful not to leave bubbles under the cover glass. (5) After dyeing with iodine solution. (6) Observing the prepared onion epidermal cells under a low-power microscope. 14. Preparation and observation of oral epithelial cells (1) Drop a drop of normal saline in the center of a clean glass slide with a dropper. (2) Rinse your mouth with cold boiled water and scrape it gently from the buccal wall of your mouth with a toothpick. (3) Put some debris attached to the toothpick into the drop of normal saline on the glass slide, and repeat it several times. (4) Cover the cover glass and be careful not to leave bubbles. (5) After dyeing with iodine solution. (6) The prepared oral epithelial cells were sliced and observed under a low-power microscope. 15, the role of cell membrane can let useful substances into the cell, keep other substances out of the cell, and at the same time, it can also discharge the waste produced in the cell. 16, the role of mitochondria and chloroplasts in energy conversion (1) Mitochondria and chloroplasts are energy converters in cells (2) Chloroplast: Chloroplast converts light energy into chemical energy and stores it in the organic matter it makes. (3) Mitochondria: release chemical energy in organic matter for cells to use. 17, the role of the nucleus in biological inheritance, the control center of the cell is the nucleus. There are chromosomes in the nucleus, DNA in the chromosomes and genetic information in the DNA. These information are actually a series of instructions to guide and control the changes of substances and energy in cells. 18, cells divide to produce new cells. Cell division refers to the division of one cell into two cells. During division, the nucleus is first divided into two parts, and then the cytoplasm is divided into two parts, each of which contains a nucleus. Finally, a new cell membrane is formed in the center of the original cell, and plant cells also form new cell walls. As a result, one cell divides into two cells. 19. Cells differentiate into tissues. Cell differentiation produces different cell groups, and each cell group is composed of cells with similar morphology and the same structure and function. Such cell groups are called tissues. 20. Explain the structural level of human body: cell → tissue → organ → system → human body 21; Explain the structural levels of plants: cells → tissues → organs → plants 22; Six organs of green flowering plants: ① roots, ② stems, ③ leaves, (belonging to vegetative organs) ④ flowers, ⑤ fruits and ⑤ seeds, (belonging to reproductive organs). 23. Organisms with only one cell, such as yeast, paramecium, Chlamydomonas, Eupolyphaga, amoeba, etc. , are single-celled organisms, can live independently and have all physiological activities. 24. Morphological structure and life activity characteristics of viruses: There are many kinds. The structure of the virus is very simple, consisting of protein's outer shell and internal genetic material, with no cell structure. Life activities: viruses can only live in living cells. 25. Pay attention to the relationship between viruses and other organisms in the biosphere, especially humans. Influenza, hepatitis, etc. Viruses cause serious harm to human health; Aids is also caused by viruses; Foot-and-mouth disease, chicken plague and many plant viruses have caused great losses to agriculture and animal husbandry. On the one hand, people try to treat and prevent viral diseases, on the other hand, they use viruses to benefit mankind. Vaccination of smallpox vaccine, oral polio vaccine, foot-and-mouth disease, chicken plague and other animal viruses can also be prevented by vaccination. These vaccines are artificially attenuated viruses. Green plants in the biosphere. Distinguish common algae, mosses and ferns. Algae: Most of them live in water and can carry out photosynthesis without differentiation of roots, stems and leaves. Common algae plants: Spirogyra, Chlamydomonas, Kelp and Porphyra. Bryophytes: Most of them live in humid land environment, and generally have stems, leaves and rhizomes. Common bryophytes: pumpkin, reed. Pteridophyte: Most of them live in humid environment and have roots, stems and leaves. Common ferns: Dryopteris nephrolepis, Selaginella Selaginella, Rhizoma Osmundae, Cimicifuga, Manjianghong. 28. Experiment: Observe the structure of the seed (1) Observe the structure of the kidney bean seed: ① Take a soaked kidney bean seed and observe its morphology. (2) Peel off the outermost seed coat of the seed and separate the closed two cotyledons. ③ Carefully observe cotyledons, radicles, embryos and hypocotyls with a magnifying glass to see what they have. (2) Observing the structure of corn seeds: ① Take a soaked corn seed and observe its shape. ② Cut the corn seeds longitudinally from the center with a blade. (3) Drop a drop of iodine solution on the outline, and then carefully observe the endosperm dyed blue and the pericarp and seed coat, radicle, embryo, hypocotyl and cotyledon that are not dyed blue with a magnifying glass to see what their characteristics are. 29. Distinguish common gymnosperms from angiosperm gymnosperms: the seeds are bare and there is no pericarp coating outside. Common gymnosperms: pine, fir, cypress, ginkgo, cycad, etc. Angiosperms: The seeds are covered with pericarp. Common angiosperms: peach, soybean, rice, rose, etc. 29. Explore the conditions of seed germination: suitable water, certain light and sufficient air. 30. There are similarities and differences in the main structure of seeds (similarities and differences between kidney bean seeds and corn seeds). Kidney bean seeds have seed coat, embryos have no endosperm, and nutrients are stored in cotyledons. Two cotyledons. Corn seeds have seed coat, embryos have endosperm, and nutrients are stored in endosperm. Cotyledons. 3 1. Conditions for seed germination: the seed must be intact and the embryo must be alive. External conditions: moisture, air and suitable temperature. 32. Nutrients needed for plant growth include water, inorganic salts (inorganic salts containing nitrogen, phosphorus and potassium are most needed) and organic matter. 33. Structure of peach blossom: flower stalk, sepals, petals, pistil (stigma, style, ovary), stamens (anthers, filaments). 34. Formation of Fruits and Seeds The ovary develops into fruit, the ovary wall develops into fruit skin, the ovule in the ovary develops into seed, and the fertilized egg in the ovule develops into embryo. 35, the characteristics of the root system suitable for water absorption The part of the root system that absorbs water is mainly the mature area of the root tip. There are a lot of root hairs in the mature area. 36, the function of the catheter to transport water and inorganic salts. 37. Photosynthetic conditions, raw materials and product conditions: light energy, chloroplast raw materials: carbon dioxide, aquatic products: organic matter, oxygen 38. Plant cells use oxygen to decompose organic matter into carbon dioxide and water, and release the energy stored in organic matter to meet the needs of life activities; This process is called respiration of plants. Breathing is mainly carried out in mitochondria. The people in Biosphere 39 show that humans originated from forest apes. Modern apes and human ancestors are both forest apes. Structure and function of male and female reproductive system Testis is the male reproductive organ that produces sperm and secretes androgen. Ovary is the female reproductive organ that produces eggs and secretes estrogen. 4 1 Physical changes in adolescence (1) The height suddenly increases, and the nervous system and cardiopulmonary functions are also obviously enhanced. (2) Rapid development of sexual organs: boys have nocturnal emission, and girls will menstruate. There are six main nutrients needed by human body: sugar, fat, protein, water, inorganic salts and vitamins. Three nutrients in human body: sugar, fat and protein. The main diseases caused by human vitamin deficiency are vitamin A deficiency: dry skin, night blindness (unable to see clearly at night), dry eye and so on. Vitamin B 1 deficiency: neuritis, beriberi (vitamin B 1 deficiency), indigestion, loss of appetite, etc. Lack of vitamin C: scurvy, decreased resistance, etc. Lack of vitamin D: rickets, osteoporosis, etc. Vitamin D can promote the absorption of phosphorus and calcium and bone development. Composition of human digestive system The digestive system consists of digestive tract and digestive glands. The digestive tract is a long tube. Digestive glands can be divided into two types: some are large digestive glands located outside the digestive tract, such as the liver, and some are small glands distributed in the digestive tract wall, such as intestinal glands. 45 The process of food digestion and nutrient absorption Starch, fat and protein in food are all organic substances with large molecules and complex structures. After entering the digestive system, it is gradually decomposed into simple materials and absorbed by the human body. This process is called digestion. Digestion is mainly carried out through the action of various digestive enzymes. Besides salivary amylase in the mouth, there are many digestive enzymes in the stomach, small intestine and other organs. Starch, maltose, glucose; Fats, glycerol, fatty acid proteins and amino acids are digested in the digestive tract and eventually decomposed into nutrients that can be absorbed by the human body, such as glucose and amino acids. Small intestine is the main organ for human body to absorb nutrition. After various nutrients are absorbed in the small intestine and other places, they are transported to the whole body with the blood of internal blood vessels. The stomach can absorb water, inorganic salts and alcohol. The large intestine absorbs a small amount of water, inorganic salts and some vitamins. Where oral sugar begins to be digested, salivary amylase and gastric protein begin to be digested, and pepsin, small intestine sugar, protein and fat can digest sugar, fat and protein's enzyme 46. Pay attention to food safety 1. Pay attention to the nutritional ingredients on food packaging, whether there are additives, production date, shelf life, manufacturer address and so on. 2. According to the production date and shelf life, it is estimated whether it will expire. 3. When you buy food, you should see whether the color of the food is fresh or not, and whether it is hard to touch with your hands. When buying fish, it depends on whether the color is shiny and whether the meat is stamped with the seal of the quarantine department. Composition of human respiratory system The respiratory system consists of respiratory tract and lungs. The nose, pharynx, larynx, trachea and bronchus in the respiratory system are the channels for gas to enter and leave the lungs, which are called respiratory tract. The nose is the starting position of the respiratory tract, and the throat is the channel for breathing and the organ for making sounds. The lung is the main organ of the respiratory system. 47. Gas exchange between alveoli and blood: In exhaled gas, the oxygen content decreases and the carbon dioxide content increases. How did this change happen? The inhaled gas reaches the alveoli formed at the end of the thinnest branch of the bronchi along the branches of the bronchi in the lung. Extraalveolar bread is surrounded by abundant capillaries. Both alveolar wall and capillary wall are flat epithelial cells. When inhaling, many alveoli bulge like small balloons, and oxygen in the air enters the blood through the alveolar wall and capillary wall. At the same time, carbon dioxide in the blood also enters the alveoli through the capillary wall and alveolar wall, and then is excreted with the exhalation process. Composition and function of blood Blood consists of plasma and blood cells. (1) plasma (morphology): After blood stratification, the upper layer is light yellow transparent liquid. (Function): Carrying blood cells, transporting substances needed to maintain human life activities and wastes generated in the body. (2) Blood cells: including red blood cells, white blood cells and platelets. A. red blood cells: (morphology) after blood stratification, red blood cells are in the lower layer and are red. Mature red blood cells have no nucleus. (Characteristics) It is easy to combine with oxygen in places with high oxygen content and separate from oxygen in places with low oxygen content. (Function): It has the function of transporting oxygen. B. White blood cells: (morphology): nucleated and spherical. Function: defense and protection characteristics: white blood cells can pass through the capillary wall, concentrate on the invasion site of bacteria, surround bacteria and devour C. Platelets: shape: irregular, without nucleus. Function: It can stop bleeding and accelerate blood coagulation. 49 The structure and function of three blood vessels The concept and function of blood vessel types Arteries transport blood from the heart to all parts of the body. Arteries are thick and elastic, while veins transport blood from all parts of the body to the heart. Arteries are thin and elastic, and capillaries connect the blood vessels between arteries and veins at least. It is a place for substance exchange between blood and cells. The tube wall is very thin and consists of a layer of epithelial cells. The structure and function of the heart is the slowest in the pipe. The heart wall is mainly composed of myocardium. The heart has four chambers: left atrium, right atrium, left ventricle and right ventricle. Only the ipsilateral atrium communicates with the ventricle (Figure P69). There are valves between aorta and left ventricle, between pulmonary artery and right ventricle, and between ipsilateral atrium and ventricle and artery. These valves are open in one direction. 5 1 systemic circulation and pulmonary circulation of human body: blood flows from the left ventricle into the aorta, then through the arteries and capillaries of the whole body, and the veins finally merge into the superior and inferior vena cava, and then flow back to the right atrium. After systemic circulation, bright red arterial blood becomes dark red venous blood. Pulmonary circulation: blood flows from the right ventricle into the pulmonary artery, then through the capillary network of the lung, and finally returns from the pulmonary vein to the left atrium. After pulmonary circulation, dark red venous blood becomes bright red arterial blood again. 52 The difference between arterial blood and venous blood Arterial blood: rich in oxygen and bright red in color. Venous blood: low oxygen content, dark red color. It is time for blood transfusion, blood type and voluntary blood donation, and the principle of importing the same type of blood should be adopted. Acceptable blood types A A, O A, AB B B O B, ABA A, B, AB, O ABO A, B, AB, O once lost blood > 1200 ~ 1500 ml, life-threatening > 800 ~ 1000 ml, dizzy. The plasma components and blood cells of patients with dark circles and cold sweat after transfusion of more than 400 ml will return to normal in a short time. Since 1998, China has implemented a voluntary blood donation system, and advocated voluntary blood donation by healthy citizens aged 18~55. Healthy adults donate 200 ~ 300ml of blood each time, which will not affect their health. Composition of human urinary system The urinary system consists of kidney, ureter, bladder and urethra. The kidney is the organ that forms urine. Ureter, bladder and catheter are the channels for urination, and bladder also has the function of temporarily storing urine. 55 Formation of Urine and Formation of Urine Excretion: The kidney is the organ that forms urine. The formation of urine mainly goes through two continuous processes: filtration and reabsorption. The formation of urine is mainly related to nephron. The glomerulus in nephron and the renal capsule wall near it play a filtering role. When blood flows through the glomerular and renal capsule wall, some substances in plasma, such as water, inorganic salts, glucose, urea, etc., except protein and macromolecules of blood cells, can enter the renal capsule through glomerular filtration. The fluid in the renal capsule is called protourine. The urine produced by human body every day is about 150 liter. When the original urine flows through the renal tubule, all glucose, most water and some inorganic salts are reabsorbed by the renal tubule, enter the capillaries around the renal tubule and return to the blood, while the remaining water, inorganic salts and urea form urine. The human body excretes about 1.5 liters of urine every day. Urine excretion: urine formed in the kidney flows into the bladder through the ureter for temporary storage. When the urine in the bladder is stored to a certain amount, people will feel micturition, micturition and urine will be excreted through the urethra. Urinating can not only discharge waste, but also regulate the balance of water and inorganic salts in the body and maintain the normal physiological functions of tissues and cells. 56. The structure of eyeball and the formation of vision: the structure of eyeball: (Figure) The main structures related to the formation of vision are cornea, iris, lens, vitreous body and retina. The formation of vision: the light reflected by external objects passes through the cornea, pupil, lens and vitreous body, refracted by the lens, and finally falls on the retina to form an object image. There are photoreceptor cells in the retina, which transmit image information to the visual center of the cerebral cortex through the optic nerve, thus forming vision. 57. Composition and function of nervous system: composition of central nervous system of brain, cerebellum and brain stem, function of peripheral nervous system of spinal cord, cranial nerve and spinal nervous system: after being stimulated, it produces excitement and conducts excitement. 58. The basic way of neuromodulation and the structure of reflex arc: The basic way of neuromodulation is reflection. The structural basis of reflection is reflex arc. Reflex: The regular response of the human body to various external or internal stimuli through the nervous system. For example, simple reflexes such as knee-jumping reflex and hand-shrinking reflex, and complex reflexes such as watching plums quench their thirst and saying that plums secrete saliva. Reflections related to language and writing, such as looking at plums to quench thirst, are complex and unique to human beings. The structure of reflex arc: receptor → afferent nerve → nerve center → efferent nerve → effector 59. The role of several hormones in human body: (1) the role of growth hormone: dwarfism caused by insufficient secretion of growth hormone in childhood. Height of patients with gigantism caused by excessive secretion of growth hormone in childhood. (2) Thyroid hormone: iodine deficiency can cause endemic goiter. Iodine deficiency in childhood can lead to dementia. (3) Insulin (islet secretion) Insufficient insulin secretion can cause diabetes. 59. Skills training: See the textbook P 109 in the second volume of Grade Three for the design control experiment. 60. Impact of human activities on organisms: (1) Deforestation seriously damages the ecological environment, exacerbates soil erosion and causes sandstorms. (2) Air pollution will form acid rain. (3) Water pollution will destroy the water ecosystem. (4) Invasion of alien species will seriously harm local organisms. (5) Human activities will also improve the ecological environment.

Grade?Eight

Other creatures in the biosphere. Characteristics of aquatic animals adapting to life in water: fish can live in water, and there are two important characteristics: one is to swim with fins to get food and defend against enemies, and the other is to breathe in water with gills. 62. The main characteristics of mammals: body surface coat; Teeth are divided into incisors, canines and molars; There is a diaphragm in the body cavity; Breathe with the lungs; The heart has four completely separated ventricles; Constant body temperature; Developed brain; Most of them are viviparous and breastfeeding. 63. Difference between warm-blooded animals and warm-blooded animals: Mammals and birds can keep their body temperature constant through their own regulation. They are all warm-blooded animals. The body temperature of other animals changes with the change of the surrounding environment, belonging to the temperature-changing animals. 64. Morphological and structural characteristics of terrestrial animals adapting to terrestrial environment: (1) The terrestrial climate is relatively dry; Accordingly, animals living on land generally have structures to prevent water loss. For example, reptiles have horny scales or nails, and insects have exoskeletons. (2) Land animals are not affected by the buoyancy of water, and generally have organs that support their bodies and movements. (3) Except for earthworms and other animals, animals living on land can generally breathe air. Various respiratory organs located in the body, such as trachea and lungs. (4) Animals living on land generally have developed sensory organs and nervous systems, which can respond to the changing environment in time. 65. Structure and characteristics of skeletal muscle: structure: tendon: thin and milky parts at both ends of skeletal muscle: thick part in the middle: muscle will contract, stop stimulating and relax no matter what kind of stimulation (including excitement from nerves). 66. Distinguish the innate behavior and learning behavior of animals: (1) Innate behavior: It is the innate behavior of animals and is determined by their genetic material. For example, bees that collect honey, and hens that have lost their cubs raise kittens. (2) Learning behavior: It 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, such as parroting, counting dogs and monkeys performing tricks. 67. The role of animals in nature: (1) plays an important role in the ecological balance center (2) promotes the material circulation of the ecosystem (3) helps plants pollinate. Spread seeds. Morphology, structure and reproduction mode of bacteria (1) Morphology of bacteria: spherical, rod-shaped and spiral hair follicle cell wall has cell membrane (2) Structure of bacteria Cytoplasmic DNA region has formed nucleus, and there is no chloroplast (3) Reproduction mode of bacteria: ① Bacteria propagate through division, and one bacteria splits into two bacteria. ② When the environment is suitable, bacteria can divide once in less than half an hour. ③ In the later stage of growth and development, some bacterial cell walls contract and thicken to form spores. (4) Spores are dormant bodies of bacteria and have strong resistance to adverse environment. ⑤ Spores are small and light, which can be scattered everywhere in the wind, but they can't germinate into bacteria when they fall in a proper environment. 69. Nutritional mode of bacteria: heterotrophic: Most bacteria can only survive by using ready-made organic matter and decomposing it into simple inorganic matter. 70. Nutrition mode of mold and mushroom: using ready-made organic matter to obtain the material and energy needed for life activities. 7 1. the difference between bacteria and fungi: bacteria: the individual is tiny, and there is no formed nucleus in the body to reproduce through division. There are no chloroplast fungi in the daughter cells: there are both small species and large species, and there are real nuclei in the cells, which can produce spores and the spores can develop into new individuals. 72. The role of bacteria and fungi in the material cycle ① Participate in the material cycle as decomposers: bacteria and fungi decompose animal and plant remains into CO2, water and inorganic salts; (2) cause diseases of animals, plants and people; (3) plants: lichens (fungi and algae) and nodules (rhizobia and plants) 72. Skills Training: See Unit 6, Biodiversity and its Protection, Page P69, Volume 73, Grade 8 [Evaluation Experiment Scheme]. Main plant groups: algae, bryophytes, ferns and gymnosperms. The main groups of animals: protozoa, coelenterates, flatworms, linear animals, annelids, mollusks, echinoderms, arthropods, fish, amphibians, reptiles, birds and mammals. 74. According to the similarity between organisms, organisms are divided into different levels of taxonomic units, from large to small, namely, boundary, phylum, class, order, family, genus and species. 75. The connotation of biodiversity includes three levels: the diversity of biological species, the diversity of genes and the diversity of ecosystems. China is the country with the richest gymnosperms, which is called "the hometown of gymnosperms". Bryophytes, ferns and seed plants in China rank third in the world. 76. Protecting the living environment of organisms and the diversity of ecosystems is the fundamental measure to protect biodiversity, and establishing nature reserves is the most effective measure to protect biodiversity.