Life at the Cellular 1 Flashcards
Describe a cell.
The functional unit of all living things.
Why are cells small?
They need a large surface area for things such as absorption and evaporation.
Give 3 features of a prokaryotic cell.
Bacteria, lack nuclear membrane, no mitochondria, no membrane bound structures.
Give 3 features of a eukaryotic cell
Human cells, multicellular animals and plants, nucleus with membrane, membrane bound structures.
What are the 2 types of stem cells?
Multipotent (can differentiate into many cell types) and pluripotent (can differentiate into all cell types).
Give the characteristics of cancer cells.
Continuously dividing, don’t co-ordinate with normal cells, don’t differentiate into specialised cells and displace and replace normal cells if not stopped.
Define apoptosis.
A central mechanism controlling multicellular development. Apoptosis is intimately coupled to cell proliferation.
Name the 4 types of tissue.
Epithelial, connective, nervous, muscle.
Define tissues.
Functional arrangement of cells.
Define organs.
Mixture of different tissues.
Define systems.
Cells or organs with similar functional roles.
What 2 components make up the cell membrane?
Lipids (amphiphatic) and proteins (span some membranes).
What are the 6 functions of the plasma membrane?
Transport, enzymatic activity, receptors for signal transduction, intercellular joining, cell-cell recognition, attachment to the cytoskeleton and extracellular matrix.
Define passive diffusion.
Concentration gradient needed, lipid soluble molecules only.
Define facilitated diffusion.
Concentration gradient needed, requires carrier proteins.
