1. Living things are objects that have life. (Coral worms and cordyceps are living things; coral, stalactites, stalagmites, and mummies are not living things.)
(1) Living things need nutrients to live
(2) Living things can breathe
(3) Living things can get rid of wastes produced in their bodies, e.g., a person can get rid of wastes in his body by sweating, urinating and exhaling gases
; the fallen leaves of a plant also carry away some of the wastes.
(4) Living things can respond to external stimuli.
(5) Living things can grow and reproduce.
(6) All living things, except viruses, are made of cells;
2. The biosphere is the home of all living things. The biosphere is the largest ecosystem.
Concept of biosphere: the place on earth suitable for survival is actually only a thin layer on the surface of the earth, scientists call
this thin layer the biosphere.
Scope: the biosphere is based on sea level, up and down the height of 10 kilometers
Biosphere range Atmosphere at the bottom of the atmospheric circle: birds, insects and bacteria that can fly, etc.
Distribution of objects Water The greater part of the circle: the layer of water up to 150 meters from the sea level
The surface of the lithosphere: the surface of all terrestrial organisms. "foothold"
The biosphere provides the basic conditions for organisms to survive: nutrients, sunlight, air suitable temperature, water, living space
Collecting information: scientific, truthful and accurate
Collecting and analyzing information Analyzing information: finding clues to inquiry and answers to questions
p>3, environmental factors affecting organisms and scientific inquiry
Abiotic factors: sunlight, temperature, moisture, air
Environmental factors Biotic factors: other organisms (predatory relationships, competitive relationships, cooperative relationships)
① Ask questions
② Make hypotheses
③ Develop a plan (controlled experiments: only one variable is different, the All other variables are the same)
Scientific inquiry ④ Implementing the plan (deriving the results of the experiment)
General process ⑤ Drawing conclusions
⑥ Expressing and communicating
4. Every organism, has a morphological structure and a way of life that is compatible with the environment in which it lives, and the adaptability of organisms is universal.
Organisms can adapt to their environments (cactus adapts to arid desert environments) or influence their environments (earthworm activity improves the soil).
In turn, the environment can influence organisms (the river is as green as blue in spring).
5, ecosystem: in a certain territory, living things and the environment formed by the unified whole. A forest, a piece of farmland, a piece of grass
Plain, a lake and so on, can be seen as an ecosystem.
6, the concept of ecosystems, composition and food chains, food webs.
Concept of ecosystem: a unified whole formed by organisms and the environment in a certain area
Producers Consumers
Decomposers
An abiotic part: sunlight, air, water and so on.
Biological Components of an Ecosystem Producers: most plants
State Living parts: consumers: most animals
System Decomposers: most bacteria, fungi
Unity Food chains and food webs: channels for the flow of matter and energy in an ecosystem.
Auto-regulatory capacity of ecosystems Concept of ecological balance
Auto-regulatory capacity: has a certain limit
7. The components of an ecosystem include: producers (plants), consumers (animals), decomposers (bacteria and fungi), and the abiotic part (sunlight, air, water, etc.). Of these, in an ecosystem, consumers are dispensable, the other three components are essential,
and producers are the most numerous.
8. Food chain: an eating and being eaten relationship formed between organisms. In an ecosystem, there are often many food chains that interlock and connect with each other to form a food web. It is along food chains and food webs that matter and energy flow in an ecosystem.
9. In an ecosystem, the number of various organisms is constantly changing, but in general, the number and proportion of various organisms in an ecosystem are relatively stable. This shows that the ecosystem has a certain automatic regulating ability, but this regulating ability has a certain limit. The greater the variety and number of organisms, the more stable the ecosystem is, and the stronger the ability to self-regulate.
10, bioconcentration: some toxic substances such as mercury, lead, DDT into the organisms, can not be discharged from the body, but only along the food chain and the food network in the organisms in the concentration of the higher and higher.
11, ecosystems in the biosphere are forest ecosystems, grassland ecosystems, marine ecosystems, freshwater ecosystems, wetland ecosystems, farmland ecosystems, urban ecosystems and so on. Among them, forest ecosystems have the largest variety and number of organisms, the strongest regulatory capacity, known as the "green reservoir"; wetland ecosystems are known as the "kidney of nature", of which the swamp is the most representative.
Unit 2, Chapter 1, Observing the Structure of Cells
1, the structure of the microscope:
(1) Optical part: eyepiece, objective lens (the field of view is bright at low magnification, the number of cells is large, and the field of view is dark at high magnification, the number of cells is small),
reflector (a plane mirror is used in strong light, and a concave mirror is used in low light).
(2) Adjustment part: coarse focusing screw (to make the barrel of the mirror fast up and down), fine focusing screw (fine adjustment), shades (large aperture and small aperture) can be adjusted to the intensity of the light
(3) support part: mirror seat, mirror arm, mirror tube, mirror column, the stage
2, the use of microscopes step by step:
(1) pick up the mirror and placed: right hand Hold the mirror arm, the left hand mirror seat, placed on the edge of the laboratory table from 7 cm, slightly to the left.
Turn the converter, so that the low-power objective lens aligned with the aperture
(2) to the light: turn the hood, so that the larger aperture aligned with the aperture
turn the reflector, so that the light is reflected into the barrel of the mirror (both eyes open at the same time, the left eye looking at the eyepiece)
placement of the specimen: the center of the aperture
(3) Observation: the barrel of the mirror is down: turn the coarse focusing screw, until the objective lens, the objective lens is slightly left side. Turn the coarse focusing screw until the objective lens is close to the specimen (eyes must look at the objective lens)
Observe the object: the left eye stares at the eyepiece, turn the coarse focusing screw counterclockwise so that the lens barrel rises slowly,
until you can see the object image clearly. Then turn the fine focusing screw to make the object image clear.
Recording: the right eye is used to record
Removal: turn the coarse focusing spiral, so that the barrel of the mirror rises, so that it is easy to remove the slide specimen.
(4) finishing: wipe: wipe the mirror body with gauze, wipe the eyepiece and objective lens with mirror paper
mirror: turn the converter so that the two high-magnification objective lenses in the shape of a "figure of eight" facing forward.
Turn the coarse focusing screw to lower the lens barrel to the lowest.
3, the object image made by the microscope is larger than the real thing; and the opposite of the real thing, inverted up and down, left and right reversed (pull the slide, the image in which direction in which direction to pull). The magnification of a microscope = objective lens magnification × eyepiece magnification. The higher the objective magnification, the longer the lens; the higher the eyepiece magnification, the shorter the lens (as shown below).
Objective magnification from low→high Eyepiece magnification from low→high
Slice: made of thin slices cut from organisms Permanent
4. Types of slide specimens Smear: made by smearing with a liquid material Temporary
Mounting: made of material torn or picked from organisms
5. Observation of plant cells:
Wipe: wipe the slide with a (clean gauze wipe slides and coverslips)
Drops: water (to facilitate the spreading of experimental materials, to prevent the plant cells from losing water and crumpling)
(1), the clinical slide Tear: use tweezers to tear the inner epidermis of the onion scales leaves
production process: show: to prevent overlapping of the cells
cover: tweezers pick up the side of the coverslip first contact with the droplets of water, and then gently cover (to prevent air bubbles)
5, observation of plant cells:
Mounted: torn or picked from organisms. Prevent air bubbles)
Dyeing: dilute iodine solution (to promote complete coloring of the specimen, to facilitate the observation of the experimental material)
Suction: absorb excess water or iodine solution with blotting paper
① cell wall: protection, support
② cell membrane: tightly adhering to the inside of the cell wall, control the entry and exit of substances
Structures that are not easy to see clearly under the microscope ① - ④ are the basic ①-④ are basic structures.
(2) Plant cells ③ Cytoplasm: a structure inside the membrane and outside the nucleus
Structure and function: ④ Nucleus: almost like a sphere, containing genetic material
⑤ Vesicles: containing the cytosol, which dissolves a variety of substances
⑥ Chloroplasts: in the cytoplasm, where photosynthesis takes place
6. (1) Why should we remove the chloroplasts from the cell wall when we make a temporary mount of a plant cell? temporary mounts, why is it necessary to stain the observation material?
(A variety of structures within plant cells are light in color and not easy to observe; staining allows the structures within the cell to be colored for easier observation.)
(2) How do you distinguish between cells and air bubbles in the field of view? (In general, air bubbles appear in the microscope field of view as darker, wider-edged images, round or oval in shape, often with a blank space inside. A gentle pressure on the coverslip with the tip of the tweezers distorts or moves the bubble.)
7, observation of animal cells:
Wipe: with clean gauze
Drops: 0.9% saline (to maintain the normal morphology of the cells)
(1), the production of the human oral cavity Scrape: the inner side wall of the oral cavity
epithelial cells temporary Coating: dispersed cells
The process of mounting: Cover: one side of the coverglass first contact with the droplets of water, then gently Cover: cover to prevent bubbles
Dye: dilute iodine solution (to promote the specimen completely colored, easy to observe the experimental material)
Suction: absorb excess water or iodine solution with absorbent paper
Cell membrane: protection, control of material in and out of the animal structure and functional units,
(2), the basic animal cells Cytoplasm: flow, promote the exchange of substances inside and outside the cell No Cell wall, large vesicles
Structure and function: nucleus: contains genetic material and chloroplasts
Chapter 2: The Life of the Cell
1.
Substances in the Cell Inorganic substances: water, inorganic salts
Organic substances: sugars, lipids, proteins, nucleic acids
Beneficial substances enter the
Cell life Cell membrane controls substances Harmful substances are prohibited from entering
Need for substances and mass to enter and exit Drain cellular metabolic wastes
Energy Energy: light, chemical, and heat can be converted into each other
There are energy converters in the cytoplasm: chloroplasts: capture light energy and turn it into chemical energy for storage
Energy converters Mitochondria: oxygenate organic matter for decomposition and release energy
2, There are energy converters in the cytoplasm: chloroplasts and mitochondria are energy converters in the cell.
(1) chloroplasts: plant cells are unique energy converter, its main function is photosynthesis, that is, the use of light energy to synthesize carbon dioxide and water into sugars and other organic matter, while producing oxygen. In addition, chlorophyll in chloroplasts can absorb light energy.
(2) Mitochondria: Mitochondria use some organic matter in the cell as fuel, so that these organic matter and oxygen combination, after a complex process, converted into carbon dioxide and water, at the same time, the chemical energy in the organic matter will be released, supplying the cell to use.
Note: Although both mitochondria and chloroplasts are energy converters in cells, chloroplasts are found only in plant cells, and mitochondria are found in both plant and animal cells.
3, the nucleus is the center of genetic information. There are substances in the nucleus that store genetic information -- DNA
Proteins:
There are chromosomes in the nucleus
DNA: It is the carrier of genetic information (genes).
(1) Chromosomes: ① Substances in the nucleus that are easily stained by alkaline dyes to a dark color. ② The number of chromosomes is certain in the cells of each organism. ③ In somatic cells, chromosomes exist in pairs, and in germ cells, chromosomes exist in singles.
(e.g., there are 23 pairs of chromosomes in a human muscle cell, 23 pairs in a fertilized egg, and 23 chromosomes in an egg cell.)
(2) Genes: DNA can be divided into many segments, each of which has specific genetic information; these segments are called genes .
4. The birth process of Dolly the cloned sheep proves that: genetic information is in the nucleus.
In vitro culture
Ewe A (provide nucleated oocytes)
Fusion cells Embryo Ewe C (surrogate) Dolly the sheep
Ewe B (provide nucleus)
5, the growth of the cell: the newly formed plant and animal cells, the volume is very small, and need to constantly absorb nutrients from the surrounding environment to build the cells, so as to make the cell size Gradually increase, this process is the growth of cells. This process is cell growth. Cell growth is not unlimited, growth to a certain extent will stop growing.
6, the growth of organisms: ① cell growth → increase in cell size
② cell division → increase in the number of cells
7, cell division: refers to the phenomenon of a cell gradually divided into two cells.
8, the process of division: (1) the nucleus of the cell is first divided equally into two. (2) The cytoplasm is divided into two. (3) Each cytoplasm contains a nucleus. (4) In the center of the original cell to form a new cell membrane (plant cells also form a cell wall).
9. The process of cell division takes place from the inside out. The number of somatic cells after division is 2 n. n represents the number of divisions.
10, Changes in chromosomes during cell division:
Process:(1) Chromosomes are doubled before cell division,
(2) During cell division, chromosomes are divided into two copies of exactly the same form and number,
(3) Two identical copies of the genetic material are brought into the two new cells respectively.
Results: Due to the doubling of chromosomes before cell division, the two new cells have the same form and number of chromosomes after cell division, and the new cells have the same form and number of chromosomes as the original cells.
Significance: ensures that the new cell contains the same genetic material as the original cell.
11, cell differentiation to form tissues:
(1) cell differentiation: in the process of development, the cells each have a different function, they are in the form, structure, but also gradually changed, this process is called cell differentiation.
(2) Organization: A group of cells formed by the association of cells with similar morphology, structure and function is called an organization.
12. Definition: A group of cells that are similar in form, identical in structure and have certain functions is called an organization.
Plant tissues: protective tissues, conductive tissues, basic tissues, meristematic tissues
Classification Animal tissues: epithelial tissues, muscular tissues, connective tissues, neural tissues
13, the order of: cell division → cell growth → cell differentiation
14, the organ: different tissues are combined together in a certain order to form a structural unit with a certain function. The structural unit:. Such as: the human stomach, intestines, liver, spleen, kidneys, etc. are organs, take the human stomach: the outer layer of the stomach is formed by the epithelial tissue of the gastric wall, the stomach plays a protective role; the stomach of the inner layer of the stomach, is composed of muscular tissues, which is conducive to the peristaltic movement of the stomach, has the function of movement. The tissues that make up the organ must be united in a certain order.
15, system: can *** with the fulfillment of one or several physiological functions of a number of organs in accordance with a certain order of combination together to constitute a system.
16, green flowering plants have six organs: (1) nutrient organs: roots, stems, leaves. (2) reproductive organs: flowers, fruits, seeds.
17, green flowering plant structural level: cell → tissue → organ → individual
animal body structural level: cell → tissue → organ → system → individual
18, single-celled organisms: the body of only one cell composition of organisms known as single-celled organisms. Most live in the water environment. Common species include yeasts, lacewings, chlamydospores, eyeworms, amoebas, and so on.
19, the structure and life of lacewing: see textbook P70
(1) the structure of lacewing: the basic structure includes the surface membrane, cytoplasm, nucleus.
(2) The life of lacewing:
①Respiration: the respiration of lacewing is realized through the epithelium, oxygen enters through the epithelium, carbon dioxide is discharged through the epithelium, and wastes produced by metabolism in the body are discharged to the outside of the body through the epithelium.
②Feeding: Crawfordia feeds through the mouth groove, forming food vesicles. The food residue formed after the food is digested by the worm is discharged from the cystic anus.
③Excretion: the excess water and metabolic wastes in the body of the grasshopper are discharged through the collecting tubes and telescopic vesicles.
④Movement: cilia are the locomotor structures of Cnidaria. It relies on the oscillation of the cilia to produce movement.
20.Response of Cnidaria to external stimuli: Although the structure of Cnidaria is very simple, it can respond to favorable or harmful stimuli from outside, i.e., it can tend to the favorable stimuli and escape from the harmful stimuli.
21, the types of viruses: viruses generally can not live independently, must be parasitized in the living cells of other organisms,
according to the different cells of the virus parasitism, it can be divided into three categories:
(1) Animal viruses: specializing in the parasitism in the cells of the body of humans and animals, the common types of influenza viruses, hepatitis viruses and so on.
(2) plant viruses; specialized in parasitism in plant body cells, common types are tobacco mosaic virus, etc..
(3) Bacterial viruses (phage): specialized in parasitizing bacterial cells, common types include E. coli virus, etc.
22, the structure and life of viruses:
(1) structure: no cellular structure, composed of a protein shell and internal genetic material.
(2) life: ① reproduction: can only be parasitized in living cells, relying on their own genetic information in the genetic material, the use of intracellular material, to create new viruses. ②Crystallization: If a virus leaves a living cell, it usually becomes crystallized, and as soon as it has a chance to invade a living cell, its life activity will start again.
Unit 3, Chapters 1 and 2, The Life of Green Plants and Angiosperms
1. Algae, bryophytes, and ferns all reproduce by spores and are sporophytes. A spore is just a cell that can only sprout if it is dispersed in a moist environment, otherwise it quickly loses its vitality.
2. Gymnosperms and angiosperms both reproduce by seeds and are seed plants. Seeds are much more viable than spores.
Algae: cladodes, sea surface, kelp, purslane
Spore plants Bryophytes: cucurbits, lichens
Plants Ferns: kidney ferns, manchurian, spinulose ferns
Seed Plants Gymnosperms: cedar, thuja, sapindales, ginkgo
Angiosperms: poplar, willow, wheat, maize, rice, peonies,
3、Groups of Plants
Groups of Plants
Living Environment
Basic Characteristics
Significance of Existence
Representative Plants
Algae plants
Mostly live in the water, and a few in the wet land
There are unicellular as well as multicellular, and there is no differentiation of roots, stems, and leaves
The plants have been known to be a source of oxygen. p>
Release oxygen; make bait for fish; edible; medicinal
Chlamydospermum, watermilfoil, staghornwort, skunk cabbage, stonewort,
Bryophytes
Wet land
Generally have true stems and leaves, (but no tubes in the stems, and no veins in the leaves,) and have no true roots, only pseudoroots. The plants are generally dwarfed.
Often used as indicator plants to detect levels of air pollution; to store water and retain soil and water
Fen mosses, wall mosses
Ferns
In moist environments in forests and mountains
Have true roots, stems, and leaves in the differentiation. The body has specialized sparing tissues and is generally taller.
Edible; medicinal; green manure and fodder, ancient ferns formed coal
Kidney fern, Manjunga,
Fetal dogbane, spinulose tree fern (a nationally protected plant)
4. Similarities and differences between gymnosperms and angiosperms:
Comparative Items
Similarities
Differences
Nudibranchs
Produce seeds and reproduce by seeds for the next
generation
Seeds are naked and not covered by pericarp
Angiosperms
Seeds are not naked and are covered by pericarp
5. Similarities and Differences Between Vegetable Bean and Corn Seeds
Compare Items
Similarities
Similarities<
Differences
Cabbage bean seeds
Germ
Both have seed coat and embryo Embryonic axis
Radicle
Cotyledons
Two cotyledons without endosperm, nutrients are stored in the cotyledons
Corn seeds
One cotyledon, endosperm, nutrients are stored in the endosperm
< p>6, the conditions of seed germination①, the external conditions of seed germination: suitable temperature, a certain amount of water and sufficient air.
②, the seed germination of its own conditions: the seed is complete, the embryo is alive, and has passed the dormant period.
7, the process of seed germination: ① seed absorption of water,
② cotyledon or endosperm in the transfer of nutrients to the radicle, germ, embryonic axis.
3) The radicle first breaks through the seed coat and develops into a root, the embryonic axis elongates, and the germ develops into a stem and leaves.
Number of sprouted seeds
Number of seeds for testing
8. Determination of germination rate: germination rate = ------ ---- ×100%
9, the structure of the root tip
(1) The root tip from the tip, in turn, is the root crown, meristematic zone, elongation zone and maturation zone four parts.
(2) ① the root crown plays a protective role belongs to the protective tissue
② the meristematic zone of the cell is small, the cell nucleus is large belongs to the meristematic tissue, has a strong ability to divide and proliferate, and can continue to divide to produce new cells, is the key part of the root growth.
③ The cells in the elongation zone elongate rapidly, and are the fastest growing part of the root.
④ The epidermal cells of the mature zone protrude outward, forming root hairs, which are the main part of the root to absorb water and inorganic salts. It belongs to the transport tissue.
10, Root growth is the result of division of the meristematic zone and elongation of the elongation zone.
That is, root growth depends on the division of cells in the meristematic zone to increase the number of cells on the one hand, and on the other hand, it depends on the elongation of the cells in the elongation zone to increase their size.
Buds Axis -→ stem
11, the structure of leaf buds Bud primordia -→ new shoots
Young leaves -→ leaves
12, the growth of plants need a variety of inorganic salts, which need the most amount of
Nitrogen-containing, phosphorus-containing, potassium-containing inorganic salts.
13.
Three types of inorganic salts
Role in plant life
Performance in case of deficiency
Nitrogen-containing inorganic salts
Facilitates cell division and growth, which leads to proliferation of branches and leaves. I.e.: "Fruitfulness"
Plants are short and thin, with yellowish leaves
Inorganic salts containing phosphorus
Promote the development of seedlings and the opening of flowers, and make the maturity of fruits and seeds earlier. I.e. "fruitful"
Plants are especially short, with dark green leaves and a mauve color
Inorganic salts containing potassium
Promote the formation and transport of starch, resulting in a "robust stalk"
The stalks are weak and easily fall over, and the tips and edges of the leaves are brown and gradually scorched.
Petals
Filaments
Stamens Anthers → pollen → pollen tubes -> sperm
Stamens Stigmas
Pistils Styles
Ovary wall - ---------- - Pericarp
14, flower Ovary Bead Being ------ seed coat Fruit
embryo Bead Seed
Oocyte-→ fertilized egg→ embryo
Flower receptacle
Calyx
(1) The most important structures of a flower are the stamen and the pistil
(2) The riddle about peanut is "Hemp house, red tent, in which there is a white fat man"; in which
"Hemp house, red tent, in which there is a white fat man"; in which
"Hemp house, red tent, in which there is a white fat man".
"Hemp house" refers to the pericarp, which develops from the wall of the ovary
"Red tent" refers to the seed coat, which develops from the beads
"White fat man" refers to the embryo, which develops from the pistil
"White fat man" refers to the embryo, which develops from the pistil. "is the embryo, which develops from the fertilized egg.
(3) The mung bean sprouts we eat are mainly developed from the elongated embryonic axis part of the mung bean seed, which develops after the fertilization of the egg cell.
15, the classification of flowers
① unisexual flowers: a flower with both pistils and stamens is called hermaphroditic flowers. For example: peach blossom
② hermaphroditic flowers: a flower only pistil or only stamens in the flower called unisex flowers. For example: cucumber, loofah flowers.
Only the pistil is called a female flower, only the stamen is called a male flower.
16, pollination and fertilization
(1), the definition of pollination: the process by which pollen falls from the anthers to the stigma of the pistil.
(2), pollination: ① autoflowering: pollen falls on the stigma of the same flower
② heteroflowering: pollen falls on the stigma of another flower by external forces.
(3) Definition of fertilization: the process by which a sperm combines with an egg cell to form a fertilized egg.
(4), the process of fertilization:
① After the pollen falls on the stigma, the mucus on the stigma stimulates the pollen to sprout and grow pollen tubes.
② The pollen tube passes through the style, enters the ovary, and reaches all the way to the ovule
③ The sperm in the pollen tube moves downward with the elongation of the pollen tube, and eventually enters the interior of the ovule.
④ The egg cell in the ovule combines with the sperm from the pollen tube to form a fertilized egg.
17. Life of angiosperms
Leaves - photosynthesis: organic matter
Seed germination → Plant growth → Flowering → Pollination → Fertilization → Fruit and Seed Formation
Roots - Absorption of water and inorganic salts
Unit 3 Chapter 3 Green Plants and the Biosphere The Water Cycle
1. Plants need water to live
① Water is an important component of the plant body. In general, water is the most abundant substance in the plant body, can reach 50% -90%.
②. Sufficient water makes the plant stiff and maintains an upright position, so that the leaves are stretched in favor of photosynthesis.
③. Inorganic salts can be absorbed by the plant body and transported to other organs of the plant body only if they are dissolved in water.
2. Water affects the distribution of plants: as different plants have different needs for water. So the amount of water in the environment, the plant body to absorb water and
3, the root is suitable for water absorption characteristics: plants mainly rely on the root to absorb water, the root is suitable for water absorption characteristics: the main part of the root to absorb water is the mature area of the root tip, the mature area has a large number of root hairs. A large number of root hairs can increase the area of water absorption. Improve the efficiency of root water absorption.
4, water transportation pathway
①, water is transported through the conduit from the root → stem → leaves, flowers, fruits and other ways.
②, the conduit is located in the xylem, belongs to the transport organization, transport water and inorganic salts, the direction is from bottom to top.
③, sieve tubes are located in the phloem and belong to the transporting tissues, transporting organic matter made by leaves to other organs, the direction is from top to bottom.
④, the formation of the layer belongs to the meristematic tissue, the cells can continue to divide, so that the stem grows thicker every year, while the formation of new phloem and new xylem. (Herbs do not have a formation layer, so they cannot make stems grow thicker year after year.)
5, transpiration: the process by which water is dissipated from the body to the outside in the form of water vapor, mainly through the leaves of the plant body.
6, transpiration is affected by light intensity, temperature, atmospheric humidity and other external conditions.
7, the significance of transpiration:
(1) Transpiration is the driving force for the absorption and transportation of water in the plant body.
(2) Transpiration promotes the transportation of inorganic salts by the plant body.
(3) Transpiration lowers the temperature of the leaves.
(4) It participates in the water cycle, increasing atmospheric humidity and precipitation.
8, regulation: stomata is the plant transpiration water loss "portal", stomata opening and closing can regulate transpiration, so that the plant body to maintain the right amount of water. At the same time, stomata are also photosynthesis absorption of carbon dioxide, respiration of carbon dioxide discharge of a major "window". Stomata is a pair of half-moon shaped cells - defense cells surrounded by the cavity, so the defense cells control the stomata open and closed, when the defense cells absorb water, stomata open, when the defense cells lose water, stomata closed.
9, the structure of the leaf blade
(1). Epidermis: ① Epidermis has an upper epidermis and lower epidermis, the cells of which are closely arranged and play a protective role.
② defense cells are distributed in the epidermal cells, generally less stomata in the upper epidermis than in the lower epidermis.
(2). Leaf pulp: it is the most dominant part of the leaf with abundant chloroplasts and is the main site of photosynthesis in the leaf.
Fence tissue: close to the upper epidermis of the leaf pulp cells are arranged closely, regular, containing more chloroplasts;
Sponge tissue: close to the lower epidermis of the leaf pulp cells are arranged laxly, irregularly, containing fewer chloroplasts.
(3), leaf veins: with conduits and sieve tubes, can transport water, inorganic salts and organic matter, with support and transport.
10, expand:
1), vegetable farmers sell vegetables to sprinkle water on the green vegetables is to keep fresh, to prevent wilting and softening of green vegetables.
2), the biggest influence on plant distribution is water. After applying fertilizer to timely watering is because inorganic salts can only be dissolved in water to be absorbed
and transported.
3), water transportation pathway in the plant: soil solution → root hair cells → root epidermis within the layers of cells → root conduit → stem conduit → leaves, flowers, fruits, seeds of the conduit → stomata → atmosphere.
4), to ensure the survival of transplanted plants are: (1) fixed trunk to reduce shaking; roots with a lump of soil (to protect the young roots and root hairs
(2) choose cloudy, rainy days, or evening transplantation; cut off some of the branches and leaves; to give the plant shade (to reduce the transpiration)
(3) timely and appropriate watering .
5), the structure of the leaf: composed of upper and lower epidermis (protective tissue) leaf flesh (nutritive tissue) leaf veins (transport tissue).
When making freehand sections, the purpose of cutting thin slices into water is to avoid the loss of water in the cells
6), the stomata are enclosed by a pair of half-moon shaped guard cells. The guard cells control the opening and closing of the stomata. Stomata open during the day and mostly close at night. The stomata of terrestrial plants are mostly located in the lower epidermis, while those of aquatic plants are mostly located in the upper epidermis.
......
The word limit for Unit 3 won't post