Overview of Cells
Cells are the building blocks of all organisms.
Only viruses are not made of cells; they also do not carry out many of the life processes.
Bacteria, fungi, plants and animals are all made up of cells.
These cells are organised into tissues. Different types of tissues form organs and organs from organ systems.
The life processes can be described as MRS GREN. Here's how it goes:
M - Movement
R - Respiration
S - Sensitivity
G - Growth
R - Reproduction
E - Excretion
N - Nutrition
Types of cells
Types of cells are:
- Single celled
- Has a cell wall and DNA but no nucleus surrounding it.
- Some are pathogenic but some can be quite useful.
- Not real cells
- Parasitic viruses "live" by hijacking host cells and taking over all their cell functions including reproduction
- Made up of mycelium (strands) of branched hyphae. These are special because they contain multiple nucluei and make up the majority of the fungus.
- Some pathogenic, causing ringworm and athlete's foot.