Stuff About Stuff

 No Brain Too Small  BIOLOGY 

Transport

normal

flaccid

isotonic

turgid

flaccid

turgid does not explode normal

flaccid

plasmolysed

Cell gains water and become turgid (stiff and hard), does not explode because of the rigid cell wall. Cells lose water and become flaccid (floppy). If it keeps loosing water, water leaves the vacuole and membrane pulls away from wall. Becomes plasmolysed.

Excytosis adds to the cell membrane while endocytosis removes part of the cell membrane. Paramecium

Osmoregulation.
This is the control of water inside a cell or organism. It is very important if you are a unicellular organism living in fresh water. Water is continually moving into the organism by osmosis (passive transport) and unless the excess water is removed the unicellular organism will explode/die. To prevent this, the unicellular organism has contractile vacuoles which collect and pump the Excess water out of the organism (active transport).

contractile vacuole

contractile vacuole

osmosis

hypotonic

Plant cells in different solutions:

phagocytosis

diffusion

Exocytosis: this is the removal of substance from the cell and is basically the reverse of endocytosis.

pinocytosis

turgid/explodes

Cell gains water and become turgid
(stiff and hard).
If water keeps entering by osmosis animal cells will explode.
Cells lose water and become flaccid
(floppy)

Endocytosis: this is the taking in of substances into the cell by the infolding of the cell membrane, to produce a vesicle. If it’s fluid being taken in – pinocytosis (cell drinking) or if it’s solids - phagocytosis (cell eating).

endocytosis

hypertonic

Red blood cells in different solutions: hypotonic isotonic hypertonic Types of active transport:

concentration gradient

Osmosis is a special type of diffusion, where water moves across a selectively permeable membrane from high water concentration to low water