2. Basic Cells Flashcards
Nucleus
control centre of cell, contains DNA
Cytoplasm
jelly-like substance inside cell that acts as support. Contains cytosol and organelles
Cell membrane
selectively permeable phospholipid bi-layer with embedded proteins, cholesterol and sugars.
Mitochondria
produces ATP from glucose, ‘powerhouse’ of the cell
Ribosomes
make proteins. Free or attached to rough ER.
Rough ER
network of membrane channels with attached ribosomes. Transports substances around the cell.
Smooth ER
membrane channels with no ribosomes. Breaks down fats, detoxifies drugs/pesticides
Golgi Apparatus
collects proteins from rough ER. Modifies, packages and sends out proteins in vesicles
Lysosomes
contain powerful enzymes to digest worn-out organelles or foreign substances.
Cytoskeleton
dense support scaffold of filaments & cylinders for intracellular transport & shape
Describe the 4 main components of the cell membrane:
- Bi-layer of phospholipids
- Proteins
- Cholesterol
- Carbohydrates (sugars) - Glycolipids and Glycoproteins
Describe the arrangement of the phospholipid bi-layer:
water-loving (hydrophilic) ends face outwards & water-hating (hydrophobic) ends face inwards, creating an oily film.
Describe the role of the embedded proteins within the cell membrane:
Receptors - for neurotransmitters and hormones
Channels – gates allowing water and other substances through
Carriers - pumping things in or out of cell
Osmosis:
movement of water across a cell membrane
Diffusion:
passive transport of molecules across cell membrane (lipid -soluable fats, oxygen, CO2)
