Cells

Cells
Hello everyone. One of the first things we lean in Biology is cells. All living organism consist of cell, and many structures (organelle) within the cell are common to most organisms, with a few exception. So what is a cell?
" A cell is the smallest unit of an organism that is considered living". There is a debate whether virus is a living organism or not, and that would be looked at later.

Cell theory
1. All organisms are composed of cells
2. Cells are alive
3. All cells come from other cells.

You should know the function of the following organelles and be able to identify them on a diagram.
1. Cell wall :       protection
                          Not found on animal cells (but on plant, fungus and bacterial cells)
2. Cell membrane/ Plasma membrane: regulate what enters and leaves the cell.
3. Nucleus:         Contains DNA and controls the cell
4. Mitochondria:  Site of cellular respiration.
5. Chloroplast   :  Site of photosynthesis, and only found in plants.
other structures of interest includes: ribosomes, endoplasmic reticulum, cytoplasm, vacuole.

Animal cell

Plant cell