valerie'E-portfolio

Cells are made up of parts that enable them to function.Animal cell and plant cell are made up of many parts.

Animal Cell:
-cytoplasm
-a nucleus
-a cell membrane
-vacoules

Vacoules are small cavities inside the cell which play role in the digestion inside the cell.
Cytoplasm is a jelly-like substance that is found in all cells.It allows substances such as food and oxygen to be transported around the cell.
Nucleus is found in the the cytoplasm.It controls everything that happen in the cell.There are thread-like structures in the nucleus.they contain information on how the cells should function.
Cell membrane holds the cytoplasm inside it.It controls the substances that go into or out of the cell.

Plant cell:
-cytoplasm
-a nucleus
-a cell membrance
-a vacuole
-a cell wall

Vacoule help plants to stand upright as plants do not have skeletal system to provide support.
Cell wall is made of a stiff material that gives the plant its shape.
Chloroplast contain chlorophyll,the green pigment that traps sunlight to make food for the plant.

Cells also multiply to replace old cells that die.This process take place in organisms all the time.

Multicellular organisms
human beings
As we grow,our body increases in size.This is because the number of cells in our body increases.Our body multiply by a process known as cell division.The nucleus and the cytoplasm of one cell divide to produce two cells.The new produced cells are identical to the original cells.

Our skin cells can live up to three weeks,while cells lining on our intestines are replaced by new cells every three days.Some cells also help to repair our damaged part of our body.

Unicellular organisms
Bacteria and paramecia

Unicellular organisms,such as bacteria and paramecia,multiply by dividing theselves.

Yeast

During the process of budding,a small bud grows from a yeast cell.The bud then increases in size and breaks away from the original yeast cell.

 From cell to organism
Human:
Cell>Tissue>Organ>System>Organism

Plants:
Cell>Tissue>Organ>System>Organism

Energy in cells
An organism needs energy because its cells need energy to grow and divide themselves.

1.Nutrients enter the cell through the cell membrane.
2.The cell converts the nutrients into energy.This is used by the cell for cell division,growth and repair.
http://www.youtube.com/watch?v=wJyUtbn0O5Y
Information in cells
When organism reproduce,they pass on certain characteristics or genetic traits to their young.These characteristics are contained as genes and stored in the thread-like structures in the cell nucleus.