Chapter 2 1 the occurrence and development of life
A, the process of the origin of life:
Primitive atmosphere → small organic molecules → large organic molecules → primitive life → primitive single-celled organisms.
The composition of primitive atmosphere: methane, ammonia, hydrogen and water vapor. There is no oxygen in the primitive atmosphere.
The formation of primitive life-primitive ocean (influenced by ultraviolet rays, lightning and cosmic rays)
2. Life origin experiment: carrion maggot experiment, gooseneck flask experiment, Miller experiment, etc.
Comparative method: according to certain standards, compare interrelated things to determine their similarities and differences.
3. The most direct evidence of biological evolution is fossils, which are the remains, relics and remains of organisms preserved in the stratum in a certain time sequence. For example: archaeopteryx fossils (ancient reptiles → ancient birds)
Fossils of simple lower organisms always appear in older strata.
Fossils of more complex and higher organisms always appear in newly formed strata.
Four. Evolution of horses
Time: 50 million years ago → 40 million years ago → 20 million years ago → today (modern horse)
Body shape: like a fox-→ like a sheep-→ a modern horse.
Limbs: short-→ slightly longer-→ slightly longer-→ current situation
Toes: 4 toes -→ 3 toes-→ the middle toe is more developed than other toes-→ the middle toe touches the ground and the lateral toe degenerates.
Living environment: shrub-→ shrub-→ arid grassland.
Verb (abbreviation for verb) bird fossils
Archaeopteryx looks like a bird: its whole body is covered with feathers, its forelimbs become wings, and its hind limbs have four toes;
Archaeopteryx is a reptile: it has three toes and claws in the front of its wings, teeth in its mouth, a long tail and a coccyx.
Six, geological age and biological evolution history table.
Geological age-divided into Archean, Archean, Paleozoic, Mesozoic and Cenozoic.
CAMBRIAN: Trilobite Age Mesozoic: Dinosaur Age (an extraordinary era)
In the early geological era, there were only the simplest organisms. In the late geological era, the more species there were, the closer they were to the existing organisms.
Seven. Biological evolution:
Primitive unicellular algae → Primitive multicellular algae → Primitive moss → Primitive ferns → Primitive seed plants (phylogenetic trees of plants).
Single-celled animals (protozoa) → invertebrates → primitive vertebrates → vertebrates (animal phylogenetic tree)
Eight. Biological evolution trend: from low to high, from simple to complex, from aquatic to terrestrial.
Nine. Darwin-biological evolution-natural selection theory
Main contents: over-reproduction: the biological reproduction ability is very strong, and the number of offspring is huge;
Genetic variation: there are various types of variation that can be passed on to future generations; (the most important factor in evolution)
Struggle for survival: future generations must compete for limited living conditions;
Survival of the fittest: Different types of variation in offspring have different abilities to compete for living conditions. In the competition for survival, individuals with favorable variation are easy to win; Individuals with unfavorable variation are easy to be eliminated.
Idea: In the competition for survival, through fierce competition, the fittest survive and the unsuitable are eliminated.
Process: Natural selection is achieved through survival competition, and the diversity and adaptability of organisms are the result of natural selection.
Significance: Organisms constantly evolve through heredity, variation and natural selection.
(Artificial selection: carefully selected and cultivated according to people's preferences, such as pet dogs, goldfish, sheep with good wool, etc. )
Examples of natural selection: 1. In the unpolluted area, the trunk is gray, which is similar to the color of the gray birch moth and has a great contrast with the color of the black birch moth. The grey birch moth is not easy to be found by insect-eating birds, and it is less preyed and has more chances of survival. Black birch moth is easy to be found by insect-eating birds, and it is hunted more and has less chance of survival.
2. In the polluted area, the trunk is black, which is similar to the color of the black birch moth and has a great contrast with the color of the gray birch moth.
The black birch moth is not easy to be found by insect-eating birds, and it is less preyed and has more chances of survival. The grey birch moth is easily attacked by insect-eating birds.
Sleep, more prey, less chance of survival.
Direct cause: the number of prey.
Indirect reason: whether there is protective color. In the polluted area, the trunk is black, similar to the color of beetles.
Ten, four modern apes: orangutans, gorillas, chimpanzees, gibbons. Similarity between apes and humans: They come from the same ancestor (forest apes), and the important symbol of the boundary between human ancestors and apes is walking upright on two feet.
XI。 evolution of mankind
Forest Australopithecus → Australopithecus → Homo habilis → Homo erectus → Homo sapiens → Modern Man.
(arboreal life) (language ability? Dress, hold javelin, hunt with spear, and make stone tools.
Important changes: the brain volume has increased significantly; Walking upright, division of labor between hands and feet; Language development, manufacturing tools.
Note: Homo erectus includes: Yuanmou, Hexian Homo erectus, Lantian Homo erectus and Beijingers.
Homo sapiens are: Jinniushan people, Dingcun people (early), Liujiang people, Ziyang people and cavemen (late).
According to different characteristics such as skin color, modern people are divided into four races: Mongolian (yellow), Caucasian (white), black (black) and Australian (brown).
Chapter 22 Species Diversity
Classification of organisms and main plant groups
1. The main characteristics of algae plants: simple structure, single-celled or multicellular individuals, no differentiation of roots, stems, leaves and other organs; There are chloroplasts in the cells, which can be used for photosynthesis; Most of them live in water, and a few live in wetlands.
Organic matter produced by algae through photosynthesis can be used as bait for fish and oxygen for aquatic animals, and it is also an important source of oxygen in the atmosphere.
The economic significance of algae: ① kelp, laver and Chinese cabbage are edible; ② Iodine, fucoidan and agar extracted from algae can be used in industry and medicine; ③ It can be used as an indicator of whether the water area is polluted (red tide phenomenon).
Second, there are two types of bryophytes: one is stem-leaf differentiation, such as cucurbit moss and wall moss; The other has no differentiation of stems and leaves, and the plant body is just a flat leaflike body, such as liverworts.
Characteristics: The roots of bryophytes are false roots, which can't absorb water and inorganic salts, while the stems and leaves of bryophytes have no conducting tissues and can't transport water. Therefore, bryophytes can't live without boiling water, and their plants are very short. Spore reproduction.
Living environment: wet ground or shady walls.
Application of bryophytes: ① Bryophytes grow densely, and the gaps between plants can store water. Therefore, bryophyte patches play a certain role in soil and water conservation of woodland and Shan Ye. (2) Bryophytes are very sensitive to toxic gases such as sulfur dioxide, and it is difficult to survive near heavily polluted cities and factories. Using this characteristic, people use bryophytes as indicator plants to monitor the degree of air pollution.
Characteristics of pteridophytes: roots, stems, leaves and other organs differentiate, and there are transport tissues and mechanical tissues inside. Most of them live in humid environment, and spores reproduce.
The economic significance of pteridophytes lies in: ① Some of them are edible; ② Some medicines are available (Nakagawa); (3) partially visible (ferns); ④ Some of them can be used as excellent green manure and feed (Manjianghong); ⑤ The remains of ancient pteridophytes turned into coal after a long time.
Ps: The green plants in the biosphere are from low to high-the spore plants are algae (lowest), bryophytes and ferns (higher); Seed plants (gymnosperms and angiosperms)
Gymnosperms: The roots and leaves are very developed, and the fertilization process does not need water, so it is suitable for living on land, and there is no fruit shell outside the seeds. China is called "the hometown of gymnosperms". Among them, the silver fir has the reputation of "giant panda in plants"
5. Angiosperms: There are developed roots, leaves, flowers, fruits and seeds. The seeds are covered with pericarp, so there is no need to water them during fertilization. It is the highest plant group. Angiosperms can be divided into monocotyledons and dicotyledons.
The similarities and differences between angiosperms and gymnosperms are pointed out. Angiosperms are more suitable for land life than gymnosperms, and they are more widely distributed and diverse in the biosphere. In angiosperms, flowers, fruits and seeds are often used as important basis for classification.
Plant groups represent the main characteristics of plant living environment.
seaweed
Most of them are unicellular or multicellular organisms living in water, with simple structure and no differentiation between Chlamydomonas and kelp.
Bryophyte plants
Plants living in dark and humid land are short, with stems and leaves and no roots, and there is no conducting tissue in the stems and leaves, so the propagation process cannot be separated from water. It is an indicator plant for monitoring air pollution, such as cucurbitaceae and liverworts.
Sheep teeth
Living in dark and humid land has real roots and leaves, and there are conductive tissues in the body. On the back of the leaves, there are sporangia, ferns and spines that produce spores.
Seed plants gymnosperms are suitable for all kinds of environments. Roots and leaves are well developed, seeds are bare, and there is no fruit envelope outside. Pine, cypress, ginkgo, cycad
Angiosperms are suitable for roots, leaves and flowers in various environments, and the seeds are wrapped with pericarp; It is a group with the highest degree of evolution in the plant kingdom: corn, rice and Chinese cabbage.
6. Compare dicotyledonous plants with monocotyledonous plants.
dicotyledon
2 structural cotyledons, 1 endosperm and endosperm cotyledons.
Root system, taproot system, fibrous root system
parallel vein
For example, melon and fruit food crops.
7. In order to scientifically classify organisms and find out their genetic relationship and evolutionary relationship, according to the similarity between organisms (morphological structure and physiological function)
According to the order from big to small: boundary, phylum, class, order, family, genus and species. Species is the most basic unit of biological classification.
Eight. The smaller the taxonomic units of different biological groups are, the fewer biological types they contain, the more the same characteristics among organisms, and the closer the genetic relationship.
Nine, the binomial method founded by Swedish scientist Linnaeus: generic name+species name.
Section III Major Animal Groups
1. Identify and distinguish invertebrates from vertebrates.
According to whether animals have backbones, they can be divided into two categories: one is vertebrates; One is invertebrate.
Fauna distribution represents the main characteristics of animals.
Attachment Sea water, fresh water and soil Earthworms and Nereis, their bodies are composed of many similar parts.
Most mollusks in seawater, fresh water and land have huge muscular feet on their ventral surfaces, which are covered with hard shells, mussels, pearls, snails and squid.
Arthropods have the largest species, the largest number and the widest distribution. They have segmented bodies, with exoskeletons and segmented appendages on the surface, and crabs (crustaceans), spiders (arachnids), centipedes (polypods) and locusts (Insecta) with eyes, tentacles and mouths on their heads.
Animal groups adapt to the environmental surface characteristics, and the reproductive mode of respiratory organs represents other animals.
Fish are egg-laying crucian carp, sharks and typical aquatic vertebrates. Their bodies are streamlined, with lateral lines on both sides and covered with scales and gills.
Amphibian larvae live in water, and adults live in wetlands near water. Bare larvae breathe through their gills, adults breathe through their lungs, and skin helps them breathe. The egg-laying frogs, toads and giant salamanders have changed from aquatic groups to terrestrial groups, and the breeding process cannot be separated from water.
The land of reptiles is generally covered with scales or breastplates, lizards that lay eggs, geckos, and creatures that really live on land.
Birds are suitable for flying in the air, and most of them are streamlined and feathered lungs.
The mammalian environment generally includes viviparous body hair and lungs, mammalian elephants, manatees and bats, which is the highest in the biological world.
Characteristics of protozoa: tiny, lowest and simplest single-celled animals, such as paramecium and amoeba. Most live in water, and a few live in animals.
Application: 1, can purify sewage, 2, excessive reproduction can cause red tide, 3, can make people sick.
3. The characteristics of coelenterates: there is a mouth without anus, and there is a digestive cavity in the body. Food enters the digestive cavity from the oral cavity, and the digested food residue is still excreted through the oral cavity. Living in water, like hydra. There are those who touch their hair.
4. Characteristics of linear animals: slender bodies, mouths and anus, such as roundworms and pinworms, are parasitic in domestic animals and make people sick.
5. Flat animal: the body and abdomen are flat, with a mouth but no anus, and both sides are symmetrical. It is parasitic in human body or animal body, which makes people suffer from parasitic diseases.
6. Annelida: The body is composed of annular segments (such as Nereis, Earthworms), slender and soft, crawling, muscle contraction, bristles supporting exercise breathing: breathing by skin on the body surface (secreting mucus),
Uses: 1, loosen soil, increase soil fertility, 2, promote material circulation, 3, can be used as medicine.
7. Echinoderm: Living in seawater, with symmetrical radiation, such as starfish, sea urchins and sea cucumbers.
8. Mollusca: Mollusca, which is divided into three parts: head, feet and visceral mass, has an outer covering and a shell to protect the body (such as squid, octopus, scallop, moth snail, etc.). )
9. Arthropods: The body has many segments, and the body surface is divided into exoskeleton, foot and antenna segments. It is a group with the largest species and quantity in the animal kingdom. It is divided into Insecta (locust), Crustacea (shrimp), Arachnida (spider) and Polypoda (centipede).
Characteristics of insects: Most insects have wings and can fly. 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. Insects are the only flying animals among invertebrates.
1. Fish
Main features: fish live in water all their lives, and most of their bodies are covered with scales. They breathe with gills and swim with fins. They have hearts, atria and ventricles.
Morphological, structural and physiological characteristics of fish in water: 1. Trunk and tail are muscular, fins maintain body balance, and swim bladder adjusts body proportion. 2。 Mucus and scales can protect and reduce resistance, and lateral lines have sensory effects. 3. Breathing: gill: gill filament (covered with capillaries, which is beneficial to gas exchange)
When a fish swims, it relies on its trunk and tail fin to generate forward power. Balance is maintained by pectoral fin, ventral fin, dorsal fin and gluteal fin. Keep moving along the caudal fin.
Uses: It is the source of protein, and can also be made into medicine feed to eat mosquitoes and prevent diseases.
2. Amphibians: larvae live in water and breathe through gills, while adults live on land and in water and breathe through lungs. Fertilization is completed in water and fertilized in vitro.
Abnormal development, naked skin, mucus secretion, assisted breathing, two atria and one ventricle of the heart, and unstable body temperature.
Application: It is the natural enemy of agricultural pests and the source of many drugs.
3. Reptiles
Main features: The body surface is covered with scales to prevent water loss. It breathes with the lungs. The heart has two atria and one ventricle. It is fertilized in vivo, and it is a warm-blooded animal. They are the first land animals to get rid of water.
Application: 1. It can be used as leather products and precious medicinal materials. It is the natural enemy of some harmful animals. Chinese alligator is a rare reptile endemic to China.
4. Birds (the body structure and physiological characteristics of birds are suitable for their flying life)
The morphological and structural characteristics of birds adapted to Yu Feixiang are as follows: the body is streamlined; Forelegs specialize into wings; The sternum protrudes to form a keel process; The body surface is covered with feathers to reduce air resistance. The physiological functions of adapting to Yu Feixiang are: the existence of airbag makes it have double breathing function (with heat dissipation); Beak and toothless, four-cavity heart, spawning, constant temperature.
Application: 1, maintaining ecological balance, controlling rodents and pests in agriculture and forestry, 2, it is an important food for human beings.
5, mammals: the body surface is covered with hair, the teeth are divided into doors, dogs, molars, there is a diaphragm in the body cavity, breathing with the lungs; The heart has four chambers, the body temperature is constant, the brain is developed, and the fetus is breastfeeding (the survival rate of offspring is high).
Section 4 Bacteria, Fungi and Viruses
Describe the main characteristics of viruses, fungi and bacteria and their relationship with human life.
The relationship between the observation structure, lifestyle and human beings of microbial groups represents organisms.
Protein shell and nucleic acid molecular core of virus electron microscope can't exist independently,
Only parasitism is beneficial: parasitic bacteria (bacteriophages),
Harmful: phage and SARS virus that cause human or animal diseases.
According to the different forms of bacteria, bacteria can be divided into cocci, bacilli, spirochetes, cell walls, cell membranes, cytoplasm and nuclear substances.
Special structure: capsule, flagella parasitism, saprophytic, autotrophic: fermentation produces substances needed by people and earth cleaners;
Harmful: lactic acid bacteria and Bacillus subtilis that make people sick.
A few fungi are small, and most of them have large cell walls, cell membranes, cytoplasm and nuclei, which are beneficial to parasitism and saprophy: they are used as food or fermentation to produce substances needed by human beings;
Harmful: yeast, ganoderma lucidum and mold that make people sick.
A, bacteria (rod, ball, spiral)
Structure: A cell structure with unformed nucleus (consisting of cell wall, cell membrane, cytoplasm and nuclear region). Some have capsules (protection), some have flagella (movement), and some form spores (dormancy body, which has strong resistance to adverse environment).
Life activities: Most of them are heterotrophic: parasitic (Bacillus anthracis), saprophytic (lactic acid bacteria), biological (rhizobia) and autotrophic (sulfide bacteria). For fission propagation, the propagation speed is fast.
Benefits: Fermentation produces monosodium glutamate, yogurt, acetic acid, biogas, etc. It can decompose biological residues into inorganic substances and restore nature to promote material circulation and kill some pests.
Hazard: make people and animals and plants sick.
Second, fungi
Structural characteristics: single cell or multicellular, with eukaryote (composed of cell wall, cell membrane, cytoplasm, nucleus, etc. ) and there are no chloroplasts.
Life activity form: heterotrophy: parasitism or saprophy
Benefits: Fermentation produces alcohol, antibiotics, organic acids, vitamins, food and edible fungi.
Hazard: Food, clothing and so on are moldy, which makes people or animals infected with diseases.
The survival of bacteria and fungi requires certain conditions, such as water, suitable temperature and organic matter. Spores are the dormant bodies of bacteria.
Yeast: It is a unicellular fungus. Under the conditions of suitable temperature, sufficient oxygen and nutrients, budding propagation can be carried out. It can be used to make wine, bread and cakes.
Mould: It is composed of hyphae, among which Penicillium: spores are turquoise and arranged in broom shape. The nutritional mode is heterotrophic. Aspergillus: Spores have many colors and are arranged radially. Penicillin is produced to inhibit the growth of bacteria, and mold parasitic in human body can cause beriberi. The nutritional mode is heterotrophic.
Mushrooms are also composed of hyphae with fruiting bodies. The folds under the cap, including the cap and the stalk, can produce spores, which reproduce.
Application: 1, partially edible, such as auricularia auricula. 2, can be used as medicinal materials. 3. Saprophytic fungi can promote the material circulation in nature. It can also make people, animals and plants sick.
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.
Note: In the material cycle of nature, bacteria and fungi decompose animal and plant remains into carbon dioxide, water and inorganic salts, which can be absorbed and utilized by plants to make organic matter. It can be seen that bacteria and fungi play an important role in the circulation of carbon dioxide and other substances in nature.
Third, the virus
Type: Virus has no cell structure. The virus has a simple structure and consists of protein shell and internal genetic material (nucleic acid molecules). Viruses can only survive in other living cells. Viruses can be divided into three types according to their parasitic cells: animal viruses, plant viruses and bacterial viruses.
Propagation mode: under the guidance of its genetic material, the virus generates new viruses in the host cell.
The relationship between virus and human beings:
Benefits: It can kill parasitic pathogenic bacteria and pests.
Hazard: It can infect people and other animals and plants with various diseases.
Inquiry activity: Question: What environmental conditions are needed for mold growth?
Assumption: Humid/warm/organic-rich environmental conditions are conducive to mold growth.
Design experiment
The growth and reproduction conditions of microorganisms and the role of food preservation methods
Air drying (sun drying, baking), pickling and dehydration inhibited the growth and reproduction of microorganisms.
Air-tight canning and vacuum packaging
Suitable temperature for cold storage, freezing and high temperature
Chemical reagents and preservatives kill microorganisms.
Chapter 23 Ecosystem and Its Stability
Concept of ecosystem: In a certain natural area, all living things and their living environment together constitute an ecosystem.
Ecosystem type: water area: ocean, fresh water and wetland; Land: forest, grassland, desert, farmland, city, etc. Ecosystems are large and small. A pond, a farmland and a river are also an ecosystem, and the biosphere is the largest ecosystem.
Components of ecosystem: Abiotic components include sunlight, air, water, soil, etc.
Biological components include-producer (plant): photosynthesis produces organic matter, which provides material and energy for various organisms in the ecosystem.
-Consumers (animals): directly or indirectly feed on green plants.
-decomposer (saprophytic microorganism): decomposes animal and plant remains and uses the organic matter and energy in them.
Ps: In an ecosystem, abiotic substances and energy, producers, consumers and decomposers are closely linked and interact to form a whole. Among them, producers are the energy source of consumers and decomposers, and also the foundation of the existence and development of ecosystems, so producers are the main components of ecosystems.
Food chain: food relationship is formed between producers and consumers, and between consumers and consumers through eating and being eaten, which is a chain connection between different organisms due to food relationship.
Food web: Many food chains are intertwined to form a complex network connection, which is called food web. The more complex the nutritional relationship structure of the ecosystem, the more stable the ecosystem. Matter and energy in the ecosystem flow along the food chain and food web.
Nutrition level classification: producer-first-class consumer-second-class consumer-third-class consumer.
Enrichment: the phenomenon that organisms absorb and accumulate a substance from the surrounding environment, so that the concentration of the substance in the organism increases continuously. Enrichment usually occurs in the food chain.
Energy flow in the ecosystem: (solar energy is the energy source of all living things)
Starting point: Producers use fixed solar energy for photosynthesis.
Flow direction: passing along the food chain (producers flow to decomposers and consumers, and consumers flow to decomposers)
Energy: the part absorbed by the next trophic level.
Loss: breath, remains and relics, etc.
Characteristics of energy flow: unidirectional flow, gradual reduction, no circulation, transmission efficiency 10-20%.
The further down the food chain, the fewer organisms, the less energy stored and the more toxic substances accumulated, forming an energy pyramid.
Material cycle (carbon cycle):
The process of transforming CO2 into carbonaceous organic matter-photosynthesis;
Transfer of carbonaceous organic matter in bio-food chain;
The process of converting carbonaceous organic matter into CO2-respiration and combustion.
Features: the substance circulates, appears repeatedly, flows circularly, does not disappear, and is used repeatedly.
1 1. The concept of ecosystem stability: There are interdependent and mutually restrictive relationships between food chains and various organisms in food webs. In the ecosystem, the number and proportion of various organisms are always kept in a relatively stable state.
12 .. Why can some ecosystems maintain certain stability? Because the ecosystem has certain self-regulation ability. The self-regulation ability of ecosystem is limited. When the external interference factors exceed this limit, the ecosystem will lose its self-regulation ability, leading to the destruction of the ecosystem.
13 .. the relationship between the structure of ecosystem and its regulation ability
The more species, the more complex the food chain and network, and the stronger the adaptability;
The fewer species, the simpler the food chain and web, and the weaker the adaptability.
14. Factors that undermine the stability of the ecosystem:
Natural factors: volcanic eruption, earthquake, debris flow, flood, etc.
Human factors: unreasonable exploitation and utilization of natural resources (over-exploitation, environmental pollution, overgrazing, destruction of vegetation, large-scale engineering construction, etc.). )
Chapter XXIV Man and the Environment
1. The impact of rapid population growth on the environment includes: food, fresh water, land and energy.
2. The problems faced by population growth are: pollution: water pollution, air pollution, solid waste gas pollution, noise pollution, etc.
3. Food problem: Food is the most basic material condition for human survival and development, so we should cultivate the habit of saving food. Moreover, saving grain can also reduce the planting area of grain, which has a certain effect on environmental protection.
4. Water resources: Water is the lifeblood of agriculture. Develop the good habit of saving water and using water scientifically to avoid water pollution.
5. With the population growth, the demand for energy is increasing, and the population explosion will accelerate the consumption of energy materials, making the limited non-renewable resources such as coal, oil, natural gas and mineral resources more and more exhausted.
6. How to solve the huge contradiction on the earth? Carrying out family planning is an effective way to control population growth.
7. Reasons for population increase: The implementation of family planning can effectively reduce the birth rate, control population growth, and finally realize the harmonious development between man and nature. The core of family planning is to control the population and improve the quality of the population. The specific requirements are: late marriage and late childbirth, fewer births and better births. implement
8. Harm of pesticides: it harms human health, destroys ecological balance, and causes huge economic losses and environmental pollution. Therefore, it is necessary to control the use of pesticides. Pests can be controlled by chemical and biological methods.
9. Ecological agriculture is an effective way to realize the sustainable development of agriculture.
Biogas fermentation: It is the process of using some microorganisms to put organic matter such as crop straw, human, poultry and livestock manure into a closed pool for fermentation to obtain biogas. The main component of biogas is methane, which is a kind of clean energy. After burning, it can produce light and heat, which can be used for cooking and lighting. The residual water after fermentation is also an organic fertilizer. Advantages of ecological agriculture: reducing waste of resources, reducing pollution and reducing pesticide pollution.
9. Give an example of human influence on the biosphere.
After deforestation, it leads to natural disasters such as soil erosion and sandstorm;
Chapter 25 Biotechnology
1. Biotechnology: refers to the technology that people use microorganisms, animals and plants to process material raw materials to provide products to serve the society.
2. Fermentation: refers to the process that some bacteria or fungi (yeast) decompose glucose into alcohol, carbon dioxide or lactic acid under anaerobic conditions. Modern generally refers to the use of certain specific functions of microorganisms or the direct application of microorganisms to the production process of certain products.
3. Lactic acid fermentation: Lactic acid bacteria can produce lactic acid from milk under anaerobic conditions and make kimchi, yogurt, cheese and other foods.
4. Alcohol fermentation: using Aspergillus, Mucor, yeast and other microorganisms, starch is first converted into glucose, and then yeast is converted into alcohol in the absence of oxygen.
5. Biogas fermentation: using anaerobic microorganisms (methanogenic bacteria)