The Human Cell Flashcards
Organisation of a Organism
Cell > Tissue > Organ > System > Organism
What are or organelles
Small organs
What are cells surrounded by?
semi-permeable ‘fluid’ plasma membrane
What is the cell membrane predominantly made up off?
Lipids that help provide structure
What is the most abundant lipid in the cell membrane
Phospholipid
Structure of phospholipid
Head: Phosphate group (Charged polar head
Hydrophilic)
Tail: Glycerol with 2 fatty acid tails (Uncharged non polar tail
Hydrophobic)
A bend in a phospholipid tail signifies what?
Its an unsaturated phospholipid
What is the function of proteins in cell membrane?
Adhesion, cellular recognition, enzymatic activity, transport and signalling (communication)
Cellular transport is?
Facilitate transport of substances from outside of the cell (extracellular) to the inside of the cell (intracellular), and vice-versa
Passive cellular transport is?
The transport of small substances through the membrane without using any energy. Examples include oxygen, carbon dioxide and lipid soluble molecules.
Facilitated cellular transport is?
A ‘gate’ or ‘carrier’ to help entry/exit to the cell. This is still passive at it does not require energy. Example, insulin facilitates the entry of glucose
Active cellular transport
When cellular energy is used to ‘force’ movement across a membrane
What is osmosis?
A balance of fluid concentration
Tonicity is?
The practical application of osmosis.
What is the Nucleus?
Contains DNA and is the site of transcription
