Three slide specimen preparation methods and storage times

1. rub

2. drip

3. tear

4.Exhibition

5. cover

6. Dye

7.suck

1. The purpose of staining: to see the structural composition of cells more clearly

2. Distinguish bubbles and cells under a microscope: the bubbles are round and have a black edge around them. The bubbles will move and deform.

3. Almost all living things are composed of cells. Various life activities of organisms are completed through cells. Cells are the basic unit of structure and function of organisms.

3. Both animal cells and plant cells have three parts: cell membrane, cytoplasm and nucleus.

4. The life activities of cells require various nutrients at all times. When these substances enter and leave the cell, they must pass through the cell membrane. There are some special structures on the cell membrane that can selectively control the substances that enter and exit the cell: the substances that cells need to live. Enter the cells, keep some substances out of the cells, and expel some unnecessary or harmful substances produced by the cell's life activities. It can be seen that the cell membrane has the function of controlling the entry and exit of substances.

5. The nucleus is a very important structure in the cell. It is the control center of the cell's life activities. There is a substance in the cell nucleus that is easily stained darkly by basic dyes - chromosomes. There are DNA residues in the chromosomes. Transfer matter - DNA.

6. The outermost layer of plant cells is the cell wall, which protects and supports the cells.

plant cells

animal cells

egg donor ewe

Nuclear donor ewe

After cell division, the nucleus divides into two, but the genetic material contained in the nucleus does not change. This is because when a cell divides, the chromosomes are duplicated, doubled in number, and then evenly distributed into the two daughter cells. The two newly formed daughter cells contain the same genetic material as the original cell, maintaining the stability of the genetic material before and after division.

After cell division, the newly formed cells absorb nutrients from the surrounding environment and grow in size from small to large. This is cell growth. Through the continuous division of cells, the number of cells increases. Through the growth of cells, the volume of cells increases. After a series of changes, the organism grows from small to large.