Cells

This week we have been discussing cells. We looked at the difference between plant and animal cells. Students should note animal cells DO NOT have cell walls, central vacuoles, and chloroplasts.

We talked about the cell parts and what they do, particularly that nucleus is the largest of the organelles and contains the chromatin (DNA).

We have been learning about sex cells, also called gametes, in the human body. Each sex cell carries 23 chrosomes in its nucleus. This is the genetic material that will be needed to make a new individual with a total of 46 chromosomes (what most people have).
Sperm are the sex cells made by the male reproductive organ.

Eggs (ova) are the sex cells made by the female reproductive organ.

We are learning about the difference in sexual and asexual reproduction. Sexual reproduction is when two sex cells join to produce a new individual. It is called fertilization the moment the sperm and egg cell meet. Asexual reproduction is when one cell makes more cells that are genetically identical to it. Types of asexual reproduction are: budding, regeneration, and fission.

Our body cells have similarities and differences. The differences are the size, shape, and function. The similarities are their needs, waste, and parts. Every cell needs water, food, and oxygen to survive. These are carried to the cells all over the body by our arteries. All cells produce waste from the food, water, and oxgen called urea and carbon dioxide. This waste is carried away from the cells by veins. The main parts of a cell are also similar. All cells have a nucleus, cytoplasm, cell membranes, and organelles.