Cellular Organisation Flashcards
If all cells are genetically identical in an organism, how do cells differentiate?
Only a few of genes are switched on in any one cell. Different genes are switched on in each type of differentiated cell.
How do different specialized cells differ?
- in shape (e.g long palisade cells)
- in proportions of cell organelles (e.g muscle cell many mitochondria)
What is a tissue?
A collection of similar cells that perform a specific function.
Give two examples of tissues
- epithelial tissues: protective/secretory function (line trachea)
- xylem: mechanical support function
What is an organ?
A combination of tissues that are coordinated to form many functions, with one predominant one
What tissues does the stomach organ have?
- muscle: churns
- epithelium: protect wall from acid
- connective tissue: hold together tissues
What tissues does a plant organ have?
- palisade: photosynthesis
- spongy mesophyll: gas diffusion
- epidermis: protect leaf
- phloem: take materials away
- xylem: bring materials to leaf
How are veins + arteries organs but capillaries aren’t?
Capillaries only made out of one tissue
What is an organ system?
Organs working together as a single unit
Name the 3 main organ systems in humans
- digestive
- respiratory
- circulatory
What is cell differentiation?
As a cell matures its structure becomes specialist to suit its specific role
