Current location - Music Encyclopedia - Chinese History - History, politics, biology and geography in the first semester of junior one.
History, politics, biology and geography in the first semester of junior one.
Outline of the final review of the seventh grade biology (Volume I)

Unit 1 Biology and Biosphere

▲ Biological characteristics: 1, biological life needs nutrition 2, bioenergy can breathe 3, bioenergy can excrete wastes generated in the body 4, bioenergy can respond to external stimuli 5, bioenergy can grow and reproduce 6, it is composed of cells (except viruses).

▲ General methods of investigation

Steps: Make clear the purpose of the investigation, determine the object of investigation, make a reasonable investigation plan, record the investigation, sort out the investigation results and write an investigation report.

▲ Classification of organisms

According to morphological structure: animals, plants and other organisms.

According to the living environment: terrestrial organisms and aquatic organisms.

By use: crops, poultry, livestock and pets.

▲ The biosphere is the home of all living things.

▲ Biosphere range: bottom of the atmosphere: birds, insects, bacteria, etc.

Most hydrosphere: the water layer within 0/50m from sea level/kloc-.

The surface of the lithosphere is the "foothold" of all terrestrial creatures.

▲ The biosphere provides basic conditions for living things: nutrients, sunlight, air and water, suitable temperature and a certain living space.

▲ The influence of environment on biology

Effects of abiotic factors on living things: light, moisture, temperature, etc.

▲ Experiment on the influence of light on the life of female rats P 15

▲ Inquiry process: 1, asking questions 2, making assumptions 3, making plans 4, implementing plans 5, drawing conclusions 6, expressing and communicating.

▲ control experiment P 15

▲ The influence of biological factors on biology:

The most common relationship is predation, but also competition and cooperation.

▲ Biological adaptation and its impact on the environment

Examples of biological adaptation to the environment P 19

Biological impact on the environment: plant transpiration can adjust air humidity, plant dead leaves and dead branches can adjust soil fertility, animal manure can improve soil, and earthworms can loosen soil.

▲ Concept of ecosystem: In a certain area, the unified whole formed by biology and environment is called ecosystem. A forest, a farmland, a grassland and a lake can all be regarded as an ecosystem.

▲ Composition of ecosystem:

Biological part: producer, consumer, decomposer

Abiotic parts: sunlight, water, air, temperature.

▲ If the organisms in every link of the ecosystem are weighed separately, under normal circumstances, the producer should be the one with a large number.

▲ Plants are producers of ecosystems, animals are consumers of ecosystems, and bacteria and fungi are decomposers of ecosystems.

▲ Food chain and food web:

The food chain begins with producers and ends with consumers. It is the "highest" animal that is not preyed by other animals.

▲ Material and energy flow along the food chain and food web.

The higher the trophic level, the less the biomass; The higher the trophic level, the accumulation (enrichment) of toxic substances along the food chain.

▲ The ecosystem has a certain ability of automatic adjustment.

Generally speaking, the number and proportion of organisms in the ecosystem are relatively stable. However, this automatic adjustment ability has a certain limit, beyond which it will be destroyed.

For example, in order to prevent birds from eating grass seeds, the experimental area is covered with nets. It turns out that the leaves of the grass in the net cover are almost eaten up by insects, and the grass grows well where there is no net cover. The reason is that the food chain is destroyed, which leads to the imbalance of the ecosystem.

▲ The biosphere is the largest ecosystem. Many impacts of human activities on the environment are global.

▲ Types of ecosystems p29

Forest ecosystem, grassland ecosystem, farmland ecosystem, marine ecosystem, urban ecosystem, etc.

▲ Biosphere is a unified whole p30

▲ Pay attention to the example on page 26 of DDT textbook.

▲ Page 27 of the textbook 1 Question Page 33 Biosphere 2

▲ Biological survival depends on the environment, adapting to the environment in various ways and influencing the environment.

Unit 2 Organisms and Cells

▲ Structure of microscope

Mirror seat: stabilize the mirror body;

Mirror column: supporting the part above the mirror column;

Mirror arm: the part holding the mirror;

Stage: a place where slide specimens are placed. There is a light hole in the center and two flat clips on both sides for fixing the observed object.

Shutter: There are round holes of different sizes on it, called aperture. Each hole can be aligned with the light-transmitting hole. Used to adjust the intensity of light.

Mirror: it can be rotated to make the light reflect upward through the light hole. Its two sides are different: the plane mirror is used when the light intensity is high, and the concave mirror is used when the light intensity is low.

Lens barrel: an eyepiece is installed at the upper end, a converter is installed at the lower end, an objective lens is installed on the converter, and a focusing screw is installed at the rear.

Focus screw: coarse focus screw: the lens barrel rises and falls greatly when it rotates; Fine quasi-focus spiral.

The relationship between rotation direction and lifting direction: rotate the focusing screw clockwise, and the lens barrel will descend; On the contrary, it will rise.

▲ Mastering the use of P37-38 diagram of microscope.

▲ The observed object image is opposite to the actual image. Note that the moving direction of the slide is opposite to the moving direction of the object image in the field of view.

▲ magnification = objective lens multiple x eyepiece multiple

▲ Biological specimens observed under a microscope should be thin and transparent, and light can pass through, so that they can be observed clearly. Therefore, it must be processed into slide specimens.

▲ Observing Plant Cells: Experimental Process P43-44

▲ The difference between slicing, smearing and mounting P42

▲ Basic structure of plant cells

Cell wall: support, protection

Cell membrane: controls the entry and exit of substances,

Cytoplasm: liquid and mobile. There are vacuoles in the cytoplasm, and many substances (such as sugar) are dissolved in the vacuoles.

Nucleus: storing and transmitting genetic information

Chloroplast: the site of photosynthesis,

Vacuole: cell fluid

▲ Experimental observation of P47 in oral epithelial cells

▲ The structure of animal cells

Cell membrane: controls the entry and exit of substances.

Nucleus: storing and transmitting genetic information

Cytoplasm: liquid and mobile.

▲ Similarities between plant cells and animal cells: they all have cell membranes, cytoplasm and nuclei.

▲ The difference between plant cells and animal cells: plant cells have cell walls and vacuoles, while animal cells do not.

▲ Cell life needs matter and energy.

▲ Cell is the basic unit of organism structure and function.

▲ Cells are the unity of matter, energy and information. Cells divide to produce new cells.

▲ substances in cells

Organic matter (usually containing carbon and combustible materials): sugars, lipids, protein and nucleic acids, which are macromolecules.

Inorganic substances (generally carbon-free): water, inorganic substances, oxygen, etc. These are small molecules.

▲ Cell membrane controls the entry and exit of substances, and it is selective for substances, and useful substances enter and waste is discharged. Pay attention to the name of the picture on page 52 of the textbook.

▲ Intracellular energy converter:

Chloroplast: Photosynthesis is the process of synthesizing carbon dioxide and water into organic matter and producing oxygen. Mitochondria: It performs respiration and is the "power factory" and "engine" in cells.

The two are related: both are energy converters in cells.

The difference between them is that chloroplasts convert light energy into chemical energy and store it in organic matter;

Mitochondria decompose organic matter and release chemical energy stored in organic matter for cells to use.

▲ Animal and plant cells have mitochondria.

▲ The nucleus is a genetic information base, and genetic information exists in the nucleus.

▲ Dolly's example p55,

▲ 1 Page 57 Question

▲ DNA, the carrier of genetic information in the nucleus.

The structure of DNA is like a spiral staircase.

▲ Genes are DNA fragments with specific genetic information.

▲DNA and protein constitute chromosomes.

Different biological individuals have completely different chromosome shapes and numbers.

Individuals of the same species maintain a certain number of chromosomes in morphology.

▲ Chromosomes are easily dyed dark by alkaline dyes.

The number of chromosomes should be kept constant, otherwise serious genetic diseases will occur.

▲ The control center of a cell is the nucleus.

▲ Cell division produces new cells.

▲ The growth of organisms from childhood is due to cell division and cell growth.

▲ Cell division

1, chromosome replication

2. The nucleus is divided into two equal nuclei.

3. The cytoplasm is divided into two parts.

4. Plant cells: form new cell membranes and cell walls in primitive cells.

Animal cells: The cell membrane gradually invades to form two new cells.

▲ The beginning of a new life-fertilized eggs

▲ All kinds of cells formed by cell differentiation can only function when they are gathered together. These cell groups composed of cells with similar morphological structure and the same function are called tissues.

▲ Different tissues are combined in a certain order to form organs.

▲ The basic tissues of animals and people can be divided into four types: epithelial tissue, connective tissue, muscle tissue and nerve tissue.

Four kinds of tissues are formed in a certain order, and one of them is dominant to form organs.

▲ It can form a system in which multiple organs complete one or several physiological functions in a certain order.

▲ Eight systems: motor system, digestive system, respiratory system, circulatory system, urinary system, nervous system, endocrine system and reproductive system.

▲ Basic structural levels of animals and people (from small to large): cells → tissues → organs → systems → animal bodies and human bodies.

▲ Plant structure level (from small to large): cells → tissues → organs → plants.

▲P65 Question 3

Section II Structural Levels of Plants

▲ Six organs of green flowering plants

Vegetative organs: roots, stems and leaves;

Reproductive organs: flowers, fruits and seeds.

In the third quarter, there is only one cell.

▲ Single-celled organisms: paramecium, yeast, Chlamydomonas, Eupolyphaga, amoeba.

▲ See page 70, 7 1 page 2 for paramecium.

▲ The relationship between single-celled organisms and humans: beneficial and harmful.

Unit 3 Green Plants in the Biosphere

▲ Pteridophytes have the differentiation of roots, stems, leaves and other organs, as well as transport tissues and mechanical tissues, so the plants are relatively tall.

▲ Spore is a germ cell.

▲ The economic significance of pteridophytes lies in: ① Some are edible; ② Some drugs are available; ③ Some are for viewing; ④ Some of them can be used as excellent green manure and feed; ⑤ The remains of ancient pteridophytes turned into coal after a long time.

▲ 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. So bryophytes can't live without boiling water.

▲ Bryophytes grow densely, and gaps between plants can store water. Therefore, bryophyte patches play a certain role in soil and water conservation of woodland and Shan Ye.

▲ 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.

▲ The main characteristics of algae plants: simple structure, single-celled or multicellular individuals, undifferentiated roots, stems, leaves and other organs; There are chloroplasts in the cells, which can be used for photosynthesis; Most of them live in water.

▲ Organic matter produced by algae plants through photosynthesis can be used as bait for fish, and the released oxygen is not only for fish to breathe, but also an important source of oxygen in the atmosphere.

▲ Economic significance of algae: ① kelp, laver and sea cabbage are edible; ② Iodine, fucoidan and agar extracted from algae can be used in industry and medicine.

Chapter IV Organism without Cell Structure-Virus

▲ Types of viruses

Depending on the host: animal virus, plant virus and bacterial virus (phage)

▲ Viral structure: the genetic material inside and outside the shell of protein.

seed plant

▲ The structure of seeds

Broad bean seeds: seed coat, embryo (embryo, hypocotyl, radicle) and cotyledon (2 pieces).

Corn seeds: pericarp and seed coat, embryo, cotyledon (1 piece) and endosperm.

▲ Seed plants are more suitable for life on land than mosses and ferns. One of the important reasons is that they can produce seeds.

▲ Remember the common gymnosperms and angiosperms.

▲ The textbook has 84 pages of tables, 85 pages of pictures and 88 pages of 2 questions.

▲ Environmental conditions for seed germination: suitable temperature, certain moisture and sufficient air.

Self-condition: A complete and energetic embryo has passed the dormancy period.

▲ Determination (calculation) and sampling inspection of seed germination rate.

▲ The process of seed germination

Absorb water and transport nutrients-radicle develops into root-hypocotyl develops into stem and leaf, radicle first breaks through seed coat, and white and fat parts of edible bean sprouts develop from hypocotyl.

▲ Plant growth

The structure of root tip and the function of each part

▲ Growth of young roots

The fastest growing part is the elongation zone.

▲ The growth of roots depends on the increase of the number of meristem cells on the one hand, and the increase of the cell volume in the elongation zone on the other hand.

▲ Branches are developed from buds, and the nutrients needed for plant growth are nitrogen, phosphorus and potassium.

▲ Flowers are developed from flower buds.

▲ Structure of Flowers (textbook 102)

▲ pollination and fertilization (textbook 103- 104)

▲ Formation of fruits and seeds

Ovary-fruit fertilized egg-embryo

Ovule-seed ovary wall-pericarp (different from pericarp in life).

▲ Textbook 105 Page 1 Title

▲ Artificial pollination

When pollination is insufficient, artificial pollination can be assisted.

▲ The life cycle of angiosperms includes seed germination, plant growth and development, flowering, fruiting, senescence and death.

▲ Green plants in the biosphere include algae, mosses, ferns and seed plants. `

▲ The life of green plants needs water.

▲ The role of water in plants

Water is a component of cells.

Water can keep the natural posture of plants.

Water is a solvent for plants to absorb and transport substances.

Water participates in the metabolism of plants.

▲ Water affects the distribution of plants.

▲ Water requirements of plants are different in different periods (P 109)

▲ Ways for water to enter plants.

The main part of root water absorption is the mature area of root tip, where there are a lot of root hairs.

▲ Structure of roots

From outside to inside: bark: phloem (with sieve tube), cambium; Xylem (with vessel)

▲ means of transportation

Conduit: upward conveying water and inorganic salts.

Screen tube: conveying the organic matter produced by photosynthesis of leaves downward.

▲ Green plants participate in the water cycle of the biosphere.

▲ Blade structure

Epidermis (divided into upper and lower epidermis), mesophyll, veins and stomata.

▲ Stomatal structure: the guard cells absorb water and swell, and the stomata open; The guard cells lose water and contract, and the stomata close.

Stomata are open during the day and closed at night.

▲ The significance of transpiration:

It can reduce the temperature of plants and prevent them from being burned.

It is the main driving force for roots to absorb water and promote water transport in the body.

It can promote the transport of inorganic salts dissolved in water in the body.

It can increase atmospheric humidity, reduce ambient temperature and increase precipitation. Promote the biosphere water cycle.

▲ Green plants are producers of organic matter in the biosphere.

Green plants make organic matter through photosynthesis.

▲ experiment of geranium

Dark treatment: put geranium in the dark for one night, and let geranium transport and consume all the starch in the leaves in the dark.

Control experiment: cover half of the upper and lower sides of a leaf with black paper. Objective: To do a control experiment to see whether starch is produced in the light and dark parts.

Decolorization: after several hours, put the leaves in water and heat them in isolation. The purpose is to decolorize and dissolve chlorophyll in leaves, which is convenient for observation.

Dyeing: dyeing with iodine solution

Conclusion: Starch turns blue when exposed to iodine, and organic matter is produced by photosynthesis in visible parts.

▲ The concept of photosynthesis: Green plants use the energy provided by light to synthesize starch and other organic substances in chloroplasts, and convert light energy into chemical energy and store it in organic substances. This process is called photosynthesis.

▲ The essence of photosynthesis: the process by which green plants use light energy to convert carbon dioxide and water into energy-storing organic matter (such as starch) and release oxygen.

▲ Significance of photosynthesis: Organic matter produced by green plants through photosynthesis not only meets the needs of their own growth, development and reproduction, but also provides basic food sources, oxygen sources and energy sources for other organisms in the biosphere.

▲ Utilization of organic matter by green plants

Objects used in architecture

Provide energy for plant life activities.

▲ The concept of respiration: 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 breathing.

▲ Significance of respiration: part of the energy released by respiration is an indispensable driving force for plants to carry out various life activities (such as cell division, absorption of inorganic salts, transportation of organic matter, etc.). ), part of it is converted into heat and radiated.

▲ Differences and connections between photosynthesis and respiration (see the end of the textbook)

▲ Formulas of photosynthesis (130) and respiration (125)

▲ Carbon and oxygen balance between green plants and biosphere

Through photosynthesis, green plants constantly consume carbon dioxide in the atmosphere, produce oxygen, and maintain the balance of carbon and oxygen in the biosphere.

▲ Relationship between respiration and production and life: intertillage and timely drainage are both for air circulation, which is beneficial to the respiration of plant roots. The respiration of plants decomposes organic matter, so when storing seeds or other organs of plants, the respiration should be reduced as much as possible, which can be inhibited by lowering the temperature, reducing the water content, reducing the oxygen concentration and increasing the carbon dioxide concentration.

▲ Relationship between photosynthesis and production and life: Effective photosynthesis of crops needs to ensure various conditions, especially illumination. Reasonable close planting. Let the leaves of crops fully receive light.

▲ Take care of vegetation and green the motherland.

▲ Main vegetation types in China.

Grassland, desert, tropical rain forest, evergreen broad-leaved forest, deciduous broad-leaved forest, coniferous forest

▲ Main problems faced by vegetation in China.

Low vegetation coverage,

Forest resources and grassland resources have been seriously damaged.

▲ The forest coverage rate in China is 16.55%.

▲ March 12 is the annual Arbor Day in China.

▲ Tropical rain forest-the lungs of the earth,

▲ The "green factory" of the biosphere-green plants.

▲ If green leaves are compared to a "factory" for making organic matter, its machine is chloroplast, its power is light, its raw materials are carbon dioxide and water, its products are organic matter and oxygen, and the conditions are light and chloroplast. A cell whose site is chloroplast and whose specific site is chloroplast.