Cell structure and organisation Flashcards
Cell membrane
Surrounds the cytoplasm, it is made out of lipids and proteins, controls substances in and out of the cell and is partially permeable only allowing small and soluble substances to pass through
Cytoplasm
Enclosed by the cell membrane, site of cellular activities and contains organelles
Vacuole
Fluid spaces enclosed by a partially permeable membrane, stores substances within the cell, plant cell has a large and central vacuole that stores sugar, mineral salts and amino acids and animal cell has numerous small vacuoles that store food and water.
Mitochondria
Oval-shaped organelles, site of aerobic respiration, breaks down food in the presence of oxygen to release energy for cellular activities
Chloroplasts
Oval structure found in plants, contains green pigment called chlorophyll for photosynthesis
Ribosome
Oval-shaped organelles, attached to organelles or lied freely in the cytoplasm, responsible for protein synthesis.
Cell wall
Surrounds the cell membrane, made out of cellulose. is fully permeable, gives the cell a fixed shape and protects it from injury.
Structure of the red blood cell and its functions
Biconcave shape- increase surface area to volume ratio for increase uptake of oxygen
Contains haemoglobin- bind to oxygen and transports it around the body
Flexible - squeeze through capillaries such as narrow blood vessels
No nucleus - Allows more packing of haemoglobin so more oxygen can be transported
Structure of the muscle cell and its function
Contains many mitochondria- break down food in the presence of oxygen to release energy for muscle contraction
Has contractile muscle fibre to relax and contract movements
Elongated and cylindrical in shape
Structure of the root hair cell and its function
Long and narrow extensions- increased surface area to volume ratio for increased rate of absorption of water and mineral salts.
Lower water potential in vacuole- allow water molecules to enter root hair cell via osmosis
