20 10 review materials of geography and biology examination

Chapter I Reproduction and Development of Organisms

Section 1 Plant Propagation

First, sexual reproduction

1, flower propagation

Calyx, corolla, etc

pillar; mainstay

Mature plant → stamen → style

Ovary → ovule → egg cell

Stamens → fertilized eggs

Anther → Pollen → Sperm ↓

Pistil → seed embryo

Filament ↓

New generation factory

2. Definition: hermaphroditic germ cells combine into fertilized eggs and develop into new individuals, which belongs to sexual reproduction.

3. Benefits: High survival rate.

Second, asexual reproduction

1, definition: A new reproductive mode in which a new individual is born by the mother without the combination of bisexual germ cells is called asexual reproduction. For example: pepper grass with leaves, potatoes with tubers and so on.

2. Benefits: Time-saving, labor-saving and high efficiency.

3. Application of asexual reproduction

(1) Grafting (apple, pear, peach): Grafting the buds or branches of one plant to another plant to make the combined two parts grow into a complete plant. When grafting, the scion (bark with bud) should be closely combined with the cambium of the rootstock to ensure the survival of the scion. Grafting includes branch grafting and bud grafting.

⑵ Cuttings (sweet potato, grape, chrysanthemum, rose, begonia purpurea): breed excellent varieties.

(3) Stratification

⑷ Tissue culture: It is a high-tech means to make plant tissues develop into new plants rapidly through cell proliferation and differentiation under artificial control by using the principle of asexual reproduction. Advantages: high technology content and fast replication speed.

Section 2 Reproduction and Development of Insects

Morphological structure and living habits

Larvae are soft and have links. Eight pairs of feet ate mulberry leaves, spun silk and molted (5 times).

The pupa is smooth, oval, motionless without eating or drinking, and plumes into moths.

Adults are soft, jointed, 8 pairs of feet, smooth, oval, scaly and hairy, and die after mating and spawning.

First, the reproduction and development of silkworms.

1, silkworm development process: silkworm lays eggs, larvae, silkworms spin cocoons, silkworm pupae, silkworm emergence, and mating between male and female moths.

2. Metamorphosis development: In the process of developing from fertilized eggs to new individuals, the development process in which the morphological structure and living habits of larvae and adults are very different is called metamorphosis.

Second, the development of other insects.

1, complete metamorphosis: the development process of eggs, larvae, pupae and adults is called complete metamorphosis. Such as silkworms, bees, cabbage butterflies, flies, mosquitoes and other insects.

2. Incomplete development: The development process of chaos, nymph and adult is called incomplete development. Such as locusts, crickets, crickets, crickets, mantis, etc.

3. Locust nymphs are similar to adults, but smaller in size, with immature reproductive organs and only wing buds, so they can jump, call jump and molt five times.

Section III Reproduction and Development of Amphibians

1. Amphibians: frogs, toads, monitor lizards and salamanders.

First, the reproduction and development of frogs.

1. Frog's reproductive development process: male frog chirping (courtship), male and female frogs embracing (fertilization), laying eggs (black: absorbing sunlight heat, shortening incubation period), tadpoles (breathing through gills), young frogs and adult frogs (breathing through lungs and skin-assisted breathing). (metamorphosis, in vitro fertilization)

2. Why are turtles and crocodiles not amphibians: ① they are not abnormal; ② They breathe with their lungs; ③ No in vitro fertilization; ④ Their eggs don't need to hatch in water; Their eggs have hard shells.

Second, the reproductive development and environment of amphibians

1. What is the effect of environmental change on the reproduction of amphibians? (1) affect racial reproduction; ② Affect individual development.

Section 4 Breeding and Development of Birds

First, observe the structure of bird eggs.

1, bird egg structure: eggshell, air chamber, eggshell membrane, egg white, lacing, yolk membrane, yolk and blastoderm.

2. Egg yolk is the main nutritional part of egg cells. The egg white outside the yolk also contains nutrients and water needed for embryonic development. Eggshell and eggshell membrane play a protective role. There are also many pores invisible to the naked eye on the eggshell.

Second, the breeding and development process of birds.

1. The reproductive development of birds generally includes several stages: courtship, mating, nesting, spawning, hatching and brooding, and each stage is accompanied by complex reproductive behavior.

Chapter II Inheritance and Variation of Organisms

The first section gene control biological characteristics

I. Biological characteristics

1, heredity: similarity between parents and children.

2. Variation: the difference between parents and offspring.

3. Character: the appearance of a part of an organism.

4. Relative traits: different manifestations of the same trait.

Second, genes control shape.

1. In the process of biological seed transfer, the genes that control the shape are passed down, and the genes determine the shape.

Section 2 Gene Transmission from Parents to Children

1, the inheritance of shape is essentially that parents pass on genes to their offspring through the process of reproduction.

2. Sperm and egg cells are the "bridge" of gene transmission between parents and children.

I. Genes and chromosomes

1, two genes determine a trait.

2. Chromosome =DNA+ protein

Gene is the smallest unit of DNA.

4. Chromosome is the carrier of DNA (DNA is on chromosome).

5. Chromosomes, DNA and genes (outside germ cells) all appear in pairs. For example, there are 23 pairs of chromosomes, including 23 pairs of DNA molecules and tens of thousands of pairs of genes, which determine the heritable traits of human body.

Second, gene transfer through sperm or egg cells.

1,1In 883, the Belgian embryologist Edward Van Beneden discovered that the sperm and egg cells of the horse-riding worm had only two chromosomes.

2. 1890, German cytologist Boveri, 189 1 year, German zoologist Henkin studied this, and confirmed that in the process of cell division to form sperm or egg cells, chromosomes will be reduced by half, not any half, and one chromosome in each pair will enter sperm or egg cells.

Dominance and Recessiveness of Genes in Section 3

First, Mendel's pea hybridization experiment

1, the father of genetics: Mendel, Austrian.

2. Dominance and recessive of genes and their relationship with shape: (1) Relative traits can be divided into dominant shape and recessive shape. (2) In the inheritance of relative traits, the genetic composition of recessive traits is only dd (the case of the same English letter represents dominant and recessive genes respectively); There are two dominant genes: Dd or DD. (3) The genome becomes Dd. Although the traits controlled by D are not expressed, D (recessive gene) is not affected by D (dominant gene) and will be inherited.

Second, it is forbidden to marry close relatives.

1. According to the laws of China, it is forbidden to get married between lineal blood relatives and collateral blood relatives within three generations.

2. Reasons for forbidding consanguineous marriage: If a family once suffered from a certain genetic disease or carried a gene for treating the disease, it is more likely that its offspring will carry the disease-causing gene. If the related offspring remarry and have children, the probability of this genetic disease will increase.

3. Significance of forbidding consanguineous marriage: forbidding consanguineous marriage is beneficial to family happiness and national prosperity.

The fourth quarter of human sex inheritance

First, the differences between male and female chromosomes.

In 1 and 1902, American cytologist Mike Lang found that the first 22 pairs of chromosomes of men and women are the same, called autosomes, and the last pair is different, called sex chromosomes.

2. 1905, American cytologist Wilson called the chromosomes in male somatic cells X chromosome and Y chromosome respectively, while the same pair of chromosomes in female is the same, both of which are X chromosomes.

Second, men and women have equal opportunities.

1, women will excrete an egg cell containing X chromosome between menstruation. Men emit hundreds of millions of sperm in a reproductive activity, one of which contains X chromosome and the other contains Y sperm.

2. The genetic material of biological traits is controlled by genes.

3. An egg cell can only combine with one sperm: identical twins and fraternal twins.

Section 5 Biological Variation

First, explore a variation phenomenon.

1, as long as there is heredity, there is variation, and variation is universal.

2. Variation depends on ① genetic material (heritable variation) ② environmental factors (non-heritable variation, but if the genetic material basis is affected, it will be inherited).

Second, human beings apply the principle of genetic variation to cultivate new varieties.

1. China applies the principle of genetic variation to cultivate new varieties: high-yield lodging-resistant wheat, space pepper, high-yield dairy cows, etc.

2. The father of hybrid rice in the world: Yuan Longping.

Chapter III Biological Evolution

The origin of life on earth

1, the primitive ancestor of mankind: forest apes.

Geological research shows that the earth was formed about 4.6 billion years ago. The primitive atmosphere includes: water vapor, hydrogen, ammonia, methane, carbon dioxide, hydrogen sulfide, etc.

3. 1953, American young Miller synthesized amino acids from primitive atmosphere.

4. 1969, it was found that the meteorite falling in the town of Carson, Australia contained amino acids that did not come from the earth. Astronomers have discovered dozens of organic substances in interstellar space.

5. Cell = nucleic acid+protein (amino acid is the smallest unit of protein).

6. The experiments of Miller and other scholars show that although life can't be formed on the primitive earth, the organic matter that constitutes life can be formed.

Scientists speculate that the temperature of the earth is gradually decreasing, and things in the primitive atmosphere condense into rain and fall to the ground. These organics enter lakes and rivers with rainwater, and final gathering is in the primitive ocean.

8. The primitive ocean is like a thin hot soup. It took about 654.38 billion years after the formation of the earth to gradually form primitive life.