Oral photography aperture

Review materials of biology at the end of the first grade.

Unit 1 Biology and Biosphere

Chapter 1 Understanding Biology

The first section biological characteristics

First, the biological characteristics:

1. Biology needs nutrition. 2. Living things can breathe. 3. Waste can be excreted.

4, stress 5, composed of cells (except viruses) 6, growth and development 7, reproduction 8, genetic variation

Second, the observation method of P2

The second part investigates the creatures around us

First, the general method 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.

Second, the 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.

Chapter II The biosphere is the home of all living things.

Section 1 Biosphere

1. Biosphere range: bottom atmosphere: birds, insects, bacteria, etc.

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

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

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

In the second quarter, the influence of environment on living things

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

Second, the experiment of the influence of light on the life of mice and girls (understanding and mastering the topic of the senior high school entrance examination paper)

Third, the process of inquiry: 1, finding problems, asking questions 2, making assumptions 3, making plans 4, implementing plans 5, drawing conclusions 6, expressing and communicating.

Four. Control experiment P 15

Five, the influence of biological factors on biology:

According to the relationship between the same species or different species, biological factors can be divided into two types: 1, and the intra-species relationship: intra-species mutual assistance (ants moving food) and intra-species struggle (two leopards competing for antelope and habitat).

2. Interspecific relationships: parasitism (ascaris lumbricoides), competition (lions and leopards compete for food) and mutual assistance (rhinoceros and hornbill).

The third quarter biological adaptation and influence to the environment

I. Examples of biological adaptation to the environment P 19

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

Section 4 Ecosystem

I. Composition of the ecosystem:

1. Biological parts: producers, consumers and decomposers.

2. Abiotic parts: sunlight, water, air and temperature.

Second, the food chain and food web:

1. The food chain starts from the producer.

2. Material-energy flows along the food chain-food web.

3. The higher the trophic level, the less the biomass; The higher the trophic level, the more toxic substances are accumulated, such as aquatic diseases in Japan.

Third, 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.

Section 5 The biosphere is the largest ecosystem

I. Types of ecosystems

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

Second, the biosphere is a unified whole p30

Pay attention to the examples of DDT (usually practice paper topics)

Unit 2 Organisms and Cells

The first chapter is to observe the cell structure.

Section 1 Practice using a microscope

I. 1. 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. Lights are used to adjust the intensity of light:

Mirror: it can be rotated to make the light reflect upward through the light hole. The two sides are different:

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 (also known as coarse adjustment): the lens barrel rises and falls greatly when it rotates; Fine-tuning focal screw (also called fine-tuning).

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.

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

1. The observed object image is opposite to the actual image.

2. Magnification = objective multiple x eyepiece multiple

3. The biological specimen observed under the microscope should be thin and transparent, and the light can pass through, so that it can be observed clearly. Therefore, it must be processed into slide specimens.

Section 2 Observation of Plant Cells

First, the difference between slicing, smearing and assembling P42

Two. Experimental process P43-44

Third, the basic structure of plant cells.

1, cell wall: support, protection

2. Cell membrane: controls the entry and exit of substances.

3. Cytoplasm: liquid and mobile.

4. Nucleus: storing and transmitting genetic information.

5. Chloroplast: the site of photosynthesis.

6. Vacuole: Cell fluid

7. Mitochondria: the place to breathe.

Section III Observation of Animal Cells

First, the oral epithelial cell experiment P47 was observed.

Second, the structure of animal cells.

1. Cell membrane: controls the entry and exit of substances.

2. Nucleus: storing and transmitting genetic information.

3. Cytoplasm: liquid and mobile.

Chapter II Cell Life

Section 1 Cell life needs matter and energy

1. Matter consists of molecules that are constantly moving. Take the experiment of sugar melting as an example to illustrate.

Molecules are not the smallest particles that make up matter. Molecules are made up of atoms. Atoms are the smallest units of matter, while cells are the structural and functional units of organisms.

Second, the substance in the cell.

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.

Third, the cell membrane controls the entry and exit of substances, and it is selective for substances, and useful substances enter and waste is discharged.

Four, the energy converter in the cell:

Chloroplast: Photosynthesis is a process in which carbon dioxide and water synthesize sugar and produce oxygen.

Mitochondria: It performs respiration and is the "power factory" and "engine" in cells.

Section 2 The nucleus is the genetic information base

First, genetic information exists in the nucleus.

Dolly's example p55

Second, the carrier of genetic information in the nucleus-DNA.

1, DNA structure is like a spiral staircase.

2. Genes are DNA fragments with specific genetic information.

Third, DNA and protein constitute chromosomes.

1, different biological individuals have completely different chromosome morphology and number.

2, individuals of the same species, chromosomes in the form and quantity to maintain a certain.

3. Chromosomes are easily dyed dark by alkaline dyes.

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

Fourth, the control center of cells is the nucleus.

The third part of cell division produces new cells.

First, the growth of organisms from childhood is due to: cell growth and cell division.

Second, 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.