1, the shape and size of the earth The earth is an irregular sphere with slightly flattened poles, with an average diameter of 637 1 meter.

2. Latitude and Latitude On the globe, the area around the globe in the east-west direction is called latitude. All latitudes are circles, which can be called latitude circles; The length of latitude circle is long or short, the equator is the longest, it gradually shortens to the poles and finally reaches a point. The latitude represents the east and west directions.

The equator is the longest latitude, about 40 thousand kilometers long. It is equal to the distance between the two poles and divides the earth into two hemispheres. The equator is zero latitude on the earth. The latitude north of the equator is called north latitude, and it is customary to use "n" as the code name; The latitude south of the equator, called south latitude, is customarily represented by "S".

3. Meridian and Longitude On the globe, the line connecting the north and south poles and perpendicular to the latitude is called meridian, also called meridian. All meridians are semicircular; They are all of the same length, indicating the north-south direction.

The zero meridian on the earth is called the prime meridian. It is divided into 1800 from the prime meridian to the east and west. 1800 in the east belongs to east longitude, so it is customary to use "e" as the code, and 1800 in the west belongs to west longitude, so it is customary to use "w" as the code.

It is customary in the world to use warp circles of 200W and 1600E as the dividing line between the eastern and western hemispheres.

4. the rotation of the earth and the alternation of day and night. the earth keeps rotating around its axis, which is called the rotation of the earth. The direction of the earth's rotation is from west to east. It takes about 24 hours to turn around, which is one day. In this way, the phenomenon of alternating day and night is produced.

5. The revolution of the earth and seasonal changes The earth revolves around the sun while rotating. The direction of the earth's revolution is also from west to east, and the time of revolution is one year. The orbital plane always keeps an angle of 66.5 with the earth axis. Because of the revolution of the earth, there are seasonal changes.

6. The division of five zones The tropics are between the Tropic of Cancer, with direct sunlight in a year, and the ground gets the most sunlight and heat, and the climate is hot all year round. The Tropic of Cancer is the dividing line between tropical and temperate zones.

The cold zone is located in the area north of the Arctic Circle and south of the Antarctic Circle, and it is extreme day and night. Polar circle is the dividing line between cold zone and temperate zone. In temperate regions between the Tropic of Cancer and the Arctic Circle, and between the Tropic of Cancer and the Antarctic Circle, there are no extreme days and nights in a year, and the solar light and heat obtained on the ground are less than those in tropical regions and more than those in cold regions, and the climate changes obviously in the four seasons.

7. Scale, legend and notes of the three elements of the map. The smaller the area drawn on the map, the more detailed the content to be represented and the larger the scale to be selected; On the contrary, the smaller the scale. On the map, it is usually "up north and down south, left west and right east"

8. Calculation method of ground height The vertical distance above sea level in a certain place on the ground is called altitude. The vertical distance from one place to another is called relative height.

9. Contour lines connect points with the same altitude, which is the contour line. Each contour line has a corresponding height value. Where the slope is steep, the contour lines are dense; Where the slope is gentle, the contour lines are sparse.

10, land and sea distribution in the world. The ocean area accounts for 7 1% of the earth, and the land area only accounts for 29%. The mainland and its nearby islands are called the mainland. The northern hemisphere is Europe and North America. most

1 1. land topography people divide the terrain into five basic types: mountains, plains, plateaus, basins and hills.

The altitude of mountainous areas is relatively high, generally more than 500 meters, with undulating peaks and steep slopes, and some mountainous areas are distributed in strips. Among them, the most prominent are two huge mountain systems composed of several tall mountains: one is the Alps-Himalayas mountain system across the south-central part of the Eurasian continent; The other is the Cordillera mountain system, which runs through North and South America, and consists of Rocky Mountain, Andes Mountain and other mountains.

The plain has a low altitude, generally below 200 meters, and the ground is flat or undulating, which is often used as "endless"

14, the temperature changes during the day, and the temperature is sometimes high and sometimes low. The highest temperature on land usually appears in the afternoon (about14); The lowest temperature appears around sunrise. In a year, the monthly average maximum temperature in most parts of the world appears in July in the northern hemisphere and 65438+ 10 in the southern hemisphere. 17, seasonal variation of precipitation: rainy areas throughout the year: there is more precipitation near the equator, such as Singapore; There is no rain all year round: there is little monthly precipitation in inland areas and polar regions, such as Cairo, Egypt; Rainy areas in summer: the east coast of the mainland near 300 ~ 400 north latitude, rainy in summer and rainy in winter, such as China; Rainy areas in winter: the west coast of the mainland near 300 ~ 400 north latitude, rainy in winter and rainy in summer, such as Rome, Italy; Perennial humid area: on the west coast of the mainland at 400 ~ 600 north latitude, the area affected by the westerly wind from the ocean all the year round is humid every month with moderate rainfall, such as London, England.

18, main climate types and distribution in the world 1. The main tropical climate type is 1, and the tropical rain forest climate is mainly distributed near the equator, with high temperature and rainy all year round. 2. The tropical grassland climate is mainly distributed in the north and south sides of the equatorial rainforest climate in Africa and South America. It is hot all year round, with obvious dry season and rainy season. 3. The tropical monsoon climate is most obvious in the Indian Peninsula and Indochina Peninsula in the south and southeast of Asia. This climate is hot all year round, and a year can also be divided into dry season and rainy season, and the wind direction changes with the seasons. In dry season, the wind blows from land to sea, and there is little rain; In the rainy season, the wind blows from the ocean to the land, and the precipitation is concentrated. 4. The tropical desert climate is mainly distributed in the west coast and inland areas of the mainland near the Tropic of Cancer. This climate is characterized by scarce precipitation, hot and dry all year round, and a large desert on the ground. 2. Temperate climate types are mainly 1, and temperate and subtropical monsoon climate are distributed in eastern Asia. Summer is hot and rainy, and winter is cold and dry. Roughly bounded by the isotherm of 65438+ 10, the average temperature in June is 0℃, with temperate monsoon climate in the north and subtropical monsoon climate in the south. 2. The Mediterranean climate is mainly located in the middle and low latitudes on the west coast of the mainland, with the most distribution along the Mediterranean coast, hot and dry in summer and mild and rainy in winter. 3. Temperate continental climate is mainly distributed in mid-latitude inland areas, with intense heat in winter, great temperature change, less precipitation and concentrated in summer. 4. The temperate maritime climate is located on the west coast of the mid-latitude continent, which is the most widely distributed in western Europe, mild and rainy, and the annual changes of temperature and precipitation are relatively small.

24. Distribution of iron, coal and oil The distribution of iron, coal and oil in the world is as follows:

1. Iron ore in the world is mainly distributed in Russia, Malaysia, China, Australia, India, Canada and the United States. These seven countries account for about 90% of the world's iron reserves.

2. Coal is mainly distributed in Eurasia and central North America in the northern hemisphere. Among the countries in the world, China, the United States, Russian and other countries have the highest coal reserves in the world.

3. The distribution of oil resources in the world is very concentrated, and the Middle East accounts for more than half of the world's oil reserves. Mainly exported to Japan, Europe and North America. 27. The most densely populated areas in the world are in eastern and southern Asia, Europe and eastern North America, and the densely populated areas are mainly located in the plains near the middle and low latitudes. In cold tundra zone, ice sheet belt, vast cold coniferous forest belt, undeveloped tropical rain forest belt, arid desert area, high plateau, mountainous area and sparsely populated area. 28. Population migration to cities and its problems. The proportion of urban population to a country's total population is often one of the criteria to measure a country's development level. More than 70% of the population in developed countries is urban, while the urban population in developing countries accounts for just over 30% of the population. Nowadays, the phenomenon of large-scale migration of rural population to cities mainly occurs in developing countries. 35. Japan's Natural and Geographical Features Japan is an island country in East Asia. Its territory consists of four big islands, Hokkaido, Honshu, Shikoku and Kyushu, and some small islands. It is relatively small and densely populated. Japan is mountainous, more than three quarters of its territory is mountainous and hilly, and the Kanto Plain near Tokyo Bay is the largest plain in Japan. Kobe and Yokohama on the Pacific coast of Honshu Island are famous seaports in China. The Japanese archipelago is located in the volcanic seismic belt around the Pacific Ocean, and there are many volcanoes. Mount Fuji is one of the famous active volcanoes and the highest mountain in Japan. Japan's monsoon climate has maritime characteristics. Compared with places at the same latitude in the Asian continent, it is warmer in winter, cooler in summer and more abundant in precipitation. Most parts of the country are covered with forests, and the rivers in mountainous areas are short and urgent, with abundant water resources. But mineral resources are scarce. See P90 in Volume I for the picture.

37. For southeast asia map, see Volume I, page 94. Southeast Asia is located in the southeast of Asia, including Indochina Peninsula and Malay Archipelago. The southern part of Indochina Peninsula is long and narrow, extending to the equator, and is called Malay Peninsula. Countries in Southeast Asia are all coastal countries or island countries except Laos, which is a landlocked country. The largest area is Indonesia. The Territory consists of more than 65,438+03,000 islands, making it the largest archipelagic country in the world. It is the country with the most volcanic activity in the world. Therefore, it is called "the country of volcanoes". The southern part of the Malay Peninsula and most parts of the Malay Archipelago are located near the equator and belong to the tropical rainforest climate. Indo-China Peninsula and northern Philippine Islands belong to tropical monsoon climate. 43. The Sahara Desert is the largest desert in the world. It starts from the Atlantic coast in the west, the Red Sea coast in the east, the Mediterranean coast in the north and the savanna in Sudan in the south, accounting for about 1/4 of Africa. There is high temperature and little rain all the year round, plants are scarce, and there is rich oil under the desert.

Junior high school biology review outline

In the seventh grade biology class.

Biological characteristics: 1. Living things need nutrition. 2. Biological energy can breathe. 3. Bioenergy can excrete wastes produced in the body. 4. Bioenergy can respond to external stimuli. 5. Bioenergy can grow and reproduce.

Biological classification: (1) animals, plants and other organisms (2) terrestrial organisms and aquatic organisms (3) crops, poultry, livestock and pets.

Biosphere range: a layer about 20 kilometers thick, including the bottom of the atmosphere, most of the hydrosphere and the surface of the lithosphere.

Basic conditions provided by the biosphere for living things: All living things, such as animals and plants, need the same basic conditions. They all need nutrition, sunshine, air and water, as well as suitable temperature and a certain living space.

Effects of abiotic factors on living things: The life span of living things will be affected by abiotic factors. When one or several factors in the environment change dramatically, it will affect the life of living things and even lead to their death.

Effects of biological factors on organisms: predation, competition and cooperation.

Ecosystem: in a certain hell, the unified whole formed by biology and environment is called ecosystem. There are producers (plants), consumers (animals) and decomposers (microorganisms).

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. In an ecosystem, there are often many food chains, which are intertwined to form a food web. Matter and energy in the ecosystem flow along the food chain and food web.

Biological system has a certain ability of automatic adjustment.

Various ecosystems: forest ecosystem, grassland ecosystem, marine ecosystem, fresh water ecosystem, wetland ecosystem, farmland ecosystem and urban ecosystem.

The biosphere is a unified whole: each ecosystem is related to other ecosystems around it: from abiotic factors, from hell relations, from creatures in the ecosystem. 7 above P3 1

Practice using microscope: first adjust the coarse quasi-focus spiral, and then adjust the fine quasi-focus spiral. 7 quotient P37

Observation of plant cells: commonly used slide specimens are: slice-made of thin slices cut from organisms; Smear-made of liquid biomaterial smear; Load-made of a small amount of material torn or taken out of an organism.

Cell wall: it is the outermost transparent thin wall that protects and supports cells.

Cell membrane: A very thin membrane near the inside of the cell wall.

Nucleus: Plant cells are approximately spherical.

Cytoplasm: Structure inside the cell membrane but outside the nucleus.

There are vacuoles in the cytoplasm, many substances are dissolved in the cytosol of vacuoles, and chloroplasts are also found in the cytoplasm of green cells of plants. Animal cells have no chloroplasts, cell walls and vacuoles.

Plant cell pattern P45 in fig. 7 and animal cell pattern P48 in fig. 7.

What is the substance in the cell? Many substances are made up of molecules.

Chloroplast converts light energy into chemical energy and stores it in the organic matter it produces.

Mitochondria use some organic substances in cells as fuel, combine with oxygen, and transform into carbon dioxide and water through complex processes, and at the same time release chemical energy from organic substances for cells to use.

There is a substance in the nucleus that stores genetic information-DNA. The carrier of genetic information is a medium, and its structure is like a spiral staircase. DNA molecules are very long and can be divided into many fragments, each of which has specific genetic information. These fragments are called genes.

DNA and protein form chromosomes.

Cell division produces new cells: the growth of organisms from small to large is inseparable from the growth and division of cells. But cells can't grow indefinitely, and some cells will divide when they grow to a certain size.

Cell division process and chromosome changes 7 P59

Cell differentiation forms tissue: epithelial tissue: muscle tissue that protects secretion and other functions; nerve tissue that contracts and relaxes; connective tissue that produces and conducts excitement: supporting, connecting, protecting, nourishing and other functions.

Tissue further forms organs, organ composition systems and human bodies.

Eight systems of human body: exercise system, digestive system, respiratory system, circulatory system, urinary system, nervous system, endocrine system and reproductive system. These eight systems coordinate with each other, so that all kinds of complex life activities in the human body can be carried out normally.

Structural level of plants: fertilized eggs form tissues and organs through cell division and differentiation, and then form plants.

Green flowering plants have six organs: roots, stems, leaves (vegetative flowers), fruits and seeds (development).

Several main organizations of plants: meristem, conservation organization, nutrition organization, transportation organization, etc.

Several unicellular organisms: yeast, paramecium, Chlamydomonas, Eupolyphaga, amoeba, paramecium.

Schematic diagram of paramecium structure, the relationship between single-celled organisms and humans: 7 on P70.

Type of virus: virus has no cell structure, much smaller than cells, and its size can only be expressed in nanometers. Viruses cannot live independently and must live in the cells of other organisms. Viruses can be divided into three types according to their parasitic cells: animal viruses, plant viruses and bacterial viruses.

The structure and life of the virus: The structure of the virus is very simple, consisting of protein's shell and internal genetic material, with no cell structure.

The relationship between virus and human: 7 on P73.

Green plants in the biosphere: algae (lowest), bryophytes, ferns (highest), seed plants (gymnosperms and angiosperms).

Seed structure (kidney bean, corn): 7 on P85.

Angiosperms are more adapted to land life than gymnosperms, and they are more widely distributed in the biosphere.

Self-conditions of seed germination: suitable temperature, certain moisture and sufficient air.

The process of seed germination: seed germination must first absorb water. Nutrients in cotyledons or endosperm are transported to radicle, embryo and hypocotyl. Subsequently, the radicle develops, breaks through the seed coat and forms roots. The hypocotyl is elongated and the embryo develops into stems and leaves.

Plant Growth: 7 on P97

Plants need nutrients: water, organic matter and inorganic salts (nitrogen, phosphorus and potassium).

The basic structure of peach blossom: 7 quotient P 102

Pollination: When the anther matures, it will naturally divide and emit pollen. The process of pollen falling from anther to pistil stigma is called pollination.

Fertilization: after the pollen falls on the stigma, it begins to germinate under the stimulation of mucus on the stigma, and grows pollen tubes, which pass through the style, enter the ovary and reach the ovule. Sperm in the pollen tube moves downward with the elongation of the pollen tube, and finally enters the ovule, which contains egg cells, and the egg cells combine with sperm from the pollen tube to form fertilized eggs.

Formation of seeds and fruits: After fertilization, petals, stamens, stigmas and styles all completed their "historical mission", so they withered. Only the ovary continues to develop and eventually becomes a fruit. Among them, the ovary wall develops into pericarp, the ovule in the ovary develops into seed, and the fertilized egg in the ovule develops into embryo.

Characteristics of root system suitable for water absorption: the part of root system that absorbs water is mainly the mature area of root tip. There are a lot of root hairs in the mature area.

Transportation route of moisture: 7+0 1 1.

Utilization of organic matter by green plant 7 P 123

Green plants and carbon-oxygen balance in biosphere (1773, experiment by British scientist Priestley) 7 P 127.

Take good care of vegetation and green the motherland. 7 quotient P 132

Under the seventh grade of biology

The origin and development of mankind: Now the ancestors of apes and human beings are forest apes. 120000 years ago, forest apes were widely distributed in Africa, Asia and Europe, especially in the tropical jungles of Africa.

Schematic diagram of human origin and development: P5 and 7

3 million years ago, human fossils: Lucy 1.75 million years ago, ancient humans: East Africans.

1929: The first Peking man skull fossil was discovered in Pei Wenzhong.

Reproductive system: Life goes through the process of combining male and female germ cells and forming new individuals through embryonic development. This process is completed by the reproductive system. Men and women have different reproductive systems, so do adults and children.

Anatomical diagram of male and female reproductive system: P9 under 7

Reproductive process: 7 times P 10

Delivery: At the 40th week of pregnancy, the fetus will be mature. The mature fetus and placenta are discharged from the mother's vagina. This process is called delivery.

The characteristics of adolescence: sudden height increase, obvious enhancement of nervous system and cardiopulmonary function. Boys have nocturnal emission, and girls will menstruate.

Adolescent sexual consciousness: initially alienated from the opposite sex, to gradually willing to approach the opposite sex, or hazy attachment to the opposite sex.

The basic requirements of family planning in China are: late marriage, late childbearing, fewer births and good births (P 19).

Nutrients in food: Food contains six kinds of nutrients such as sugar, fat, protein, water, inorganic salts and vitamins.

Sugar, fat and protein in food: provide energy for P22.

Water and inorganic salts: water can transport energy, and inorganic salts include calcium, phosphorus, iron, iodine and zinc. 7 Xiap24

Vitamin: 7 P26

Changes of food in digestive system: The oral cavity is the beginning of the digestive system, including teeth, tongue and salivary glands. The salivary gland has a catheter, and the saliva it secretes enters the mouth through the catheter.

Composition and function of digestive system: 7 P32.

Digestive system: digestive tract: a long tube. Digestive glands are divided into two categories: some are large digestive glands located in the digestive tract, such as the liver; Some are small glands distributed on the inner wall of digestive tract, such as intestinal glands.

Absorption of nutrients: food is digested in the digestive tract and eventually decomposed into nutrients that can be absorbed by the human body, such as glucose and amino acids.

Rational nutrition and food safety: 7 P37

Respiratory system: The respiratory system of human body consists of respiratory tract and lungs. The respiratory system has the structure and function suitable for gas exchange with the outside world.

Respiratory tract: nose, pharynx, larynx, trachea and bronchus, which are channels for gas to enter and leave the lungs.

The function of respiratory tract: the passage of gas, which processes the inhaled gas and makes the gas in the lungs warm, moist and clean.

Gas exchange between the lung and the outside world: the lung is the main organ of the respiratory system, located in the chest cavity, one on the left and one on the right. The left lung has two pages and the right lung has three leaves. Unconsciously, your lungs are already exhaling and inhaling rhythmically.

Mode of lung movement: 7. P49。

Gas exchange between alveoli and blood: 7 P50.

A person breathes more than 20,000 times a day and exchanges at least 1 10,000 liters of gas with the environment every day.

Composition of blood: Blood consists of plasma and blood cells. There is a thin layer of white material at the junction of the two layers, which is white blood cells and platelets.

Plasma: substances needed to transport blood cells and maintain human life activities and wastes produced in the body.

Blood cells: Blood cells include red blood cells, white blood cells and platelets. After blood stratification, red blood cells are red in the lower layer, and white blood cells and platelets are fine white at the junction of the two layers.

Red blood cells: The most red blood cells are round cakes with concave sides. They have no nucleus and hemoglobin that can carry oxygen.

Leukocyte: It has a nucleus, which is larger than red blood cells. It can penetrate the capillary wall, surround and devour bacteria.

Platelet: the smallest blood cell, with no nucleus and irregular shape, which can release substances related to coagulation.

Arteries, capillaries and veins: 7 under P67.

Cardiac anatomical map: 7P68.

Schematic diagram of heart work: 7 times of P69.

Blood circulation pattern diagram: 7 P70

Systemic circulation: blood enters the aorta from the left ventricle, then flows through arteries, capillary networks and veins at all levels of the body, and finally collects in the superior and inferior vena cava and returns to the right atrium. This circulatory pathway is called systemic circulation.

Pulmonary circulation: the blood flowing back to the right atrium is pressed into the pulmonary artery through the right ventricle, flows through the capillary network of the lung, and then flows back to the left atrium from the pulmonary vein. This circulation path is called pulmonary circulation.

Systemic circulation means that blood starts from the left side of the heart and returns to the right side. Pulmonary circulation means that blood starts from the right side of the heart and returns to the left side, thus forming a complete blood circulation path.

1900, the Austrian scientist Landstein discovered the blood type.

Blood transfusion relation table: 7 times that of P76.

Kidney: the organ that forms urine. Each kidney includes about 654.38+0 million structural and functional units, which are called nephrons. Each unit consists of glomerulus, renal capsule and renal tubule.

Schematic diagram of internal structure of kidney: P8 1 7.

Urine formation chart: 7 P82.

Bladder: temporary storage of raw urine.

Basic structure and function of eyeball: 7 times P89

The process of vision formation: the light reflected by external objects passes through cornea, pupil, lens and vitreous body in turn, is refracted by lens, and finally falls on retina, forming an object image. There are photoreceptor cells in the retina. These cells transmit image information to a certain area of the brain through the optic nerve, and people have vision.

Basic structure and function of the ear: 7 P93.

The process of hearing formation: P94 under 7

Composition of nervous system: The nervous system consists of brain, bone marrow and its nerves.

Composition and function of nervous system: 7 P98.

Neurons: Neurons, also called nerve cells, are the basic units that constitute the structure and function of the nervous system. There are hundreds of millions of neurons in the human body.

The basic regulation of nerves is reflex.

Reflex: The regular response of the human body to various external or internal stimuli through the nervous system.

Schematic diagram of steamed bread flying: 7 times P 102.

The human body regulates its own life activities through various simple or complex reflexes, so as to quickly respond appropriately to internal and external stimuli.

The main endocrine glands that constitute the endocrine system: 7 P 106.

The life activities of human body are mainly regulated by nervous system, but also influenced by hormone regulation.

In the eighth grade biology class

Fish: So fish can live in water, and there are two important characteristics: one is to get food and defend against enemies through the swing of tail and the coordinated swimming of fins, and the other is to breathe in water with gills.

Other aquatic animals:

Coelenterate: there is no anus in the mouth, food enters the digestive cavity through the mouth, and the digested food residue is still excreted through the mouth.

Molluscs: Molluscs are protected by shells (squid and octopus are degenerated shells and mollusks).

Crustacea: There are hard nails on the body surface.

The growth environment of earthworms and the internal structure of rabbits are P 16.

Animals flying in the air: Animals flying in the air in nature appeared hundreds of millions of years ago. First, insects in invertebrates, then birds in vertebrates and bats in mammals. They are all terrestrial animals and are suitable for flying.

There are more than 9,000 species of birds and 6,543.8+0,000 species of insects in the world.

Birds are suitable for flying: birds are covered with feathers, and their forelimbs become wings, which has the ability to fly quickly; The car body has airbags; Body temperature is high and constant. The body structure and physiological characteristics of birds are adapted to their flying life.

Characteristics of insects: 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.

Insect's body: it is divided into three parts: head, chest and abdomen. The moving organs-wings and feet are born in the chest. Exoskeleton is a tough shell covering the insect body, which can protect and support the soft organs inside and prevent the evaporation of water in the body.

Classification of insects: the classification of insects belongs to arthropods (the body is composed of many segments; There is an exoskeleton on the body surface; Feet and antennae are divided into arthropods)

Amphibians: Amphibians live in amphibious life, breathing with lungs and breathing with skin. This animal is called amphibian.

Animal movement: The pattern diagram of bones and joints of rabbits. The relationship between muscles and bones and joints is on P29.

Coordination of bones, joints and muscles: the change of bone position produces movement, but the bone itself cannot move. The movement of bones depends on the traction of skeletal muscles.

Exercise needs the control and adjustment of motor system and nervous system. It needs energy supply, so it also needs the cooperation of digestive system, respiratory system and circulatory system.

Animal behavior: feeding behavior, defensive behavior, reproductive behavior, migration behavior, etc. It can also be divided into innate behavior and learning behavior.

Characteristics of social behavior: animals with social behavior often form certain organizations within groups, with clear division of labor among members, and some groups also form hierarchies. This is the main feature of social behavior.

Information exchange among groups: 8 on P39

Ecological balance: There is an interdependent and restrictive relationship 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.

Animals and bioreactors: Using bioreactors to produce certain substances needed by human beings can save the cost of building factories and purchasing instruments and equipment, and reduce complex production procedures and environmental pollution.

Animals and bionics: Scientists imitate some structures and functions of organisms through careful observation and study, and invent and create various instruments and equipment, which is bionic.

Colony: Colony is relatively small with smooth or sticky surface or rough and dry. Fungal colonies are usually several to dozens times larger than bacterial colonies. The colonies formed by molds are often fluffy, flocculent or cobweb-like, sometimes red, brown, green, black and yellow.

Discovery of bacteria: Dutch Levin Hook made a microscope of 200~300 times to observe the tartar of the elderly and found bacteria.

Pasteur used a goose neck bottle to prove that bacteria were produced by pre-existing bacteria. Lactic acid bacteria and yeast were also found, and the methods of preserving wine, pasteurization and preventing surgical infection were put forward. Later, he was called "the father of microbiology".

Morphology and structure of bacteria: the individual of bacteria is very small, about 654.38+0 billion bacteria are as big as a grain of rice. The morphology of bacteria can only be observed by high-power microscope or electron microscope ... Bacteria have no P60 on nucleus 8.

Bacterial reproduction: Bacteria reproduce by division. Some bacteria will shrink in the late growth stage, the cell wall will thicken and form spores. Spore is a dormant body of bacteria and has strong resistance to adverse environment.

Fungal reproduction: Fungi reproduce their offspring by producing a large number of spores.

The role of bacteria and fungi in nature: 1. Participate in the material cycle as a decomposer. 2. Bring diseases to animals, plants and people. 3. Live with animals and plants.

Human Utilization of Bacteria and Fungi: 8 on P70

Biological classification: classification is based on the morphological and structural characteristics of organisms. The basic unit of classification is species.

Plant classification: 8 P8 1.

The biological classification from big to small is: boundary, phylum, class, order, family, genus and species.

Creatures under the eighth grade

Plant propagation:

Sexual reproduction: They bloom, pollinate, bear fruit, and reproduce from the seeds of fruits. The embryo in the seed is developed by combining bisexual germ cells into fertilized eggs.

Asexual reproduction: new individuals are directly produced by the mother and do not need the combination of bisexual germ cells.

Grafting: Grafting the buds or branches of one plant to another plant, so that the two parts can be combined to grow into a complete plant.

Complete metamorphosis: after four stages: egg, larva, pupa and adult, this development process is complete metamorphosis.

Incomplete metamorphosis: after three stages: egg, nymph and adult, this development process is incomplete metamorphosis.

Reproductive and developmental processes of birds: including courtship, mating, nesting, spawning, hatching and brooding.

Genetic control of biological characteristics: heredity refers to the similarity between parents and children, and variation refers to the differences between parents and children and between offspring individuals. The inheritance and variation of organisms are realized through reproduction and development.

Relative traits: different manifestations of the same trait.

Genes and chromosomes: There are chromosomes in the nucleus, and there are protein and DNA in the chromosomes. The morphology and number of chromosomes in each biological cell are determined.

There are 23 pairs of chromosomes in biological cells (except germ cells) and human somatic cells.

1883, Belgian embryologist Edward van Beneden discovered that the sperm and chromosomes of Ascaris carinii only have two pairs of chromosomes.

Gene transfer through sperm or egg cells

1858~ 1865 Austrian Mendel discovered the dominance and recessive of genes.

1902, American cytologist Mike Lang discovered that a pair of chromosomes in male cells are different from other chromosomes, which he called sex chromosomes.

1905, American cytologist Wilson said that male sex chromosomes are X and Y chromosomes, and the same pair of chromosomes in female cells are the same, both of which are X chromosomes.

From 65438 to 0953, Miller, a young American scholar, simulated primitive earth conditions and atmospheric composition and synthesized a variety of amino acids.

The trend of biological evolution: from simple to complex, from low to advanced, from aquatic to terrestrial.

Darwin's theory of nature: in nature, all biological individuals have the characteristics of heredity and variation. Only those individuals with favorable variation can easily survive in struggle for existence and pass these variations on to the next generation, while those individuals with unfavorable variation are easily eliminated. In this way, the creatures in nature, through fierce competition for survival, the fittest survive and the unsuitable are eliminated, which is natural selection. Organisms continue to evolve through heredity, variation and natural selection.

Pathogen: bacteria, viruses and parasites that cause infectious diseases.

Three basic links in the epidemic of infectious diseases

Source of infection: a person or animal that can spread pathogens.

Transmission route: the route through which pathogens leave the source of infection and reach healthy people. Such as air transmission, food transmission, biological media transmission and so on.