Cell biology

• What are two types of eukaryotic cells?

  Animal and plant
• What type of cell are bacteria?

  Prokaryotic
• Where is DNA found in animal and plant cells?

  In the nucleus
• What is the function of the cell membrane?

  Controls movement of substances in and out
• What is the function of mitochondria?

  Site of respiration to transfer energy
• What is the function of chloroplasts?

  Contain chlorophyll for photosynthesis
• What is the function of ribosomes?

  Enable production of proteins
• What is the function of the cell wall?

  Strengthens and supports the cell
• What is the structure of the main genetic material in a prokaryotic cell?

  Single loop of DNA
• How are electron microscopes different from light microscopes?

  Use beams of electrons instead of light
• What is the function of a red blood cell?

  Carries oxygen around the body
• Give three adaptations of a red blood cell.

  No nucleus, contains haemoglobin, bi-concave shape
• What is the function of a nerve cell?

  Carries electrical impulses around the body
• Give two adaptations of a nerve cell.

  Branched endings, myelin sheath insulates axon
• What is the function of a sperm cell?

  Fertilises an egg
• Give two adaptations of a sperm cell.

  Tail, contains lots of mitochondria
• What is the function of a palisade cell?

  Carries out photosynthesis in a leaf
• Give two adaptations of a palisade cell.

  Lots of chloroplasts, located at top surface
• What is the function of a root hair cell?

  Absorbs minerals and water from soil
• Give two adaptations of a root hair cell.

  Long projections, lots of mitochondria
• What is diffusion?

  Net movement of particles from high to low concentration
• Name three factors that affect the rate of diffusion.

  Concentration gradient, temperature, surface area
• How are villi adapted for exchanging substances?

  Large surface area, one cell thick, good blood supply
• How are the lungs adapted for efficient gas exchange?

  Alveoli, moist membranes, good blood supply
• How are fish gills adapted for efficient gas exchange?

  Large surface area, thin layer of cells, good blood supply
• What is osmosis?

  Diffusion of water through a partially permeable membrane
• What is active transport?

  Movement of particles against a concentration gradient
• Why is active transport needed in plant roots?

  Mineral ions must move against concentration gradient
• What is the purpose of active transport in the small intestine?

  Sugar absorbed when concentration is lower in intestine