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Anonymous users2024-02-06Send me an email and I'll send you seven or eight.
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Anonymous users2024-02-05With the exception of viruses, living things are made up of cells.
2. Cells are the basic units of biological structure and function.
3. The basic conditions provided by the biosphere for the survival of organisms are: nutrients, sunlight, air and water, suitable temperature and a certain living space.
4. The environmental factors that affect the life of organisms can be divided into two categories: biological factors and abiotic factors.
5. The biosphere includes the bottom of the atmosphere, the entire hydrosphere, and the upper layer of the lithosphere.
6. The composition of the ecosystem includes the biotic and abiotic parts, of which the biotic part includes producers, consumers and decomposers; Abiotic parts such as sunlight, air, water, etc.
7. The relationship between producers and consumers is mainly the relationship between eating and being eaten, so that the food chain is formed. The food chains are intertwined with each other to form a food web. It is along the food chain and food web that matter and energy flow in ecosystems.
8. The largest ecosystem is the biosphere.
9. Steps for using the microscope: taking and placing the lens, aligning the light, observing, cleaning and closing the lens.
10. What the eyepiece sees is an inverted image; The magnification of a microscope is the product of the magnification of the objective lens and the eyepiece. 10x30＝300
11. If you see the image in the field of vision to the lower left, the specimen should move the image to the lower left to move to **; The specimen moves upwards to the right, and the object seen in the field of view moves towards the lower left.
12. The glass slide says 'up and down', and what you see in the field of vision is '' Method: Left-hand (or right-handed) 1800 of the piece of paper that says 'up and down'.
13. Onion scale leaf epidermal cell temporary loading production: preparation (wipe clean, drip water); Production (peeling off the inner epidermis, flattening; coverslips); Dyeing (dropping iodine solution, water absorption).
14. Staining: make the cell structure clearer, but affect the biological activity of living cells, and even make living cells die; Live cells and their biological activity should not be stained.
15. Temporary loading of human oral epithelial cells: preparation (wipe clean, drip normal saline); Preparation (a few scrapes, smearing; coverslips); Dyeing (dropping iodine solution, water absorption).
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Anonymous users2024-02-04Review the syllabus.
Structure of the seed.
Fava bean seeds: seed coat, germ (germ, hypocotyl, radicle), cotyledons (2 pieces).
Corn seeds: peel and seed coat, germ, cotyledons (1 piece), endosperm.
The life of angiosperms.
Section 1 Seed germination.
1. Conditions required for seed germination.
Environmental conditions: suitable temperature, a certain amount of moisture, sufficient air.
Self-condition: the grains are full, the embryo is complete, has vitality, and has passed the dormant period.
2. Determine the germination rate of seeds and sample testing.
3. The process of seed germination.
Water absorption - nutrient transport - radicle development into roots - germcocotyl development into stems and leaves.
Section 2 Plant Growth.
The structure of the bud. 1. Bud axis - develops into a stem.
2. Bud primordium - develops into lateral buds.
3. Growth point - the bud axis continues to elongate and produce new bud primordium and leaf primordium.
4. Leaf primordium - develops into young leaves].
4. Nutrients needed for plant growth.
Flowering and fruiting.
1. Flowers develop from flower buds.
Second, the structure of the flower.
Petals, receptacles, calyxes, stamens (anthers, filaments), pistils (ovary, columella, stigma).
3. Pollination and fertilization.
Fruit and seed formation.
Ovary – fruit Fertilized egg – embryo Fertilized polar nucleus – endosperm.
Ovules – seeds Bead quilt – seed coat.
Greenery in the biosphere.
Section 1 Algae, mosses and ferns.
1. The aerial part of the fern is not the stem, but its compound leaves; The underground part is the underground stems and roots.
2. Ferns have the differentiation of roots, stems, leaves and other organs, and also have conductive tissues and mechanical tissues, so the plants are relatively tall.
3. The spore is a kind of germ cell, and the sporangia are not visible at any time, but can be seen during reproduction in summer, and when the spores germinate, they can form a protophyll.
An organism with only one cell.
1. Single-celled organisms: yeast, paramecium, chlamydomonas, euglena, amoeba.
2. Paramecium.
The basic tissues of animals and humans can be divided into four types: epithelial tissue, connective tissue, muscle tissue, and nervous tissue.
Bonus 3q
Of course, you have to listen carefully in class, and the homework left by the teacher must be completed independently, and you should ask questions frequently if you don't know, or wait for the teacher to talk in class (junior high school class time is relatively relaxed, the teacher should teach the exercises, if you don't talk about it, ask the teacher, the teacher will not say you). In addition, don't look for too many and too difficult extracurricular questions, which will increase the pressure, but a moderate amount is still possible. The content of the third year of junior high school here is more than the content of the second year of junior high school, and the part of electricity must be learned well. >>>More
Do more exercises. Teach you a quick way to learn, it's as simple as writing the answers on the practice questions and looking at them again, whatever method you use, just memorize them. It's a quick approach, but it's also flawed, and you can find out for yourself!
Grasp the key points, the focus is on the acid and alkali salt part, the experiment of gas, and the calculation of the solute mass fraction in the solution, and the other parts pay attention to the mastery of basic knowledge.
Our math teacher is almost like this, we have become accustomed to these strange words over time, and sometimes we will laugh out loud when we hear the teacher talk about pidgin. You don't really have to care about the strange things the teacher says, just humor it, and it will pass, and it can be turned into motivation for learning! You know, math is math and math teachers are math teachers, and the two can't be confused, even if you hate math teachers, you can't hate math! >>>More