Cell Biology (AQA)

Cards (36)

  • All living things are made out of cells.
  • Cells can either be prokaryotic or eukaryotic.
  • The nucleus contains the genetic material that controls the cell's activities.
  • Cytoplasm is a gel-like substance in which most of the chemical reactions takes place.
  • The cell membrane holds the cell together and controls which substances can go in and out of the cell.
  • Plant cell wall is made up of cellulose.
  • The permanent vacuole of the plant cell contains cell sap (solution made up of sugar and salts)
  • Photosynthesis occurs in the chloroplasts
  • chloroplasts contain a green pigment called chlorophyll, which absorbs sunlight for photosynthesis
  • Bacterial cells don't have a nucleus. They have a singular circular strand of DNA that floats freely in the cytoplasm.
  • magnification = image size / real size
  • the function of the sperm cell is to get male DNA to the female DNA
  • the sperm cell has a long tail & a streamlined head to help it swim to the egg
  • sperm cells have lots of mitochondria
  • sperm cells also have enzymes in its head to digest the egg cell membrane.
  • The function of the nerve cell is to carry electrical signals from one part of the body to another
  • nerve cells are long in structure and have branched connections at their ends to connect to other nerve cells. This creates a network throughout the body
  • function of muscle cells is to contract quickly
  • muscle cells are long and contain lots of mitochondria to generate the energy needed for contraction
  • chromosomes contain genetic information
  • the nucleus contains all of the genetic material in the form of chromosomes
  • chromosomes are coiled up lengths of DNA molecules
  • stem cells can divided into different types of cells based on the given instructions
  • stem cells are found in early embryos and are found in bone marrow for adults
  • embryonic stem cells are used to make insulin-producing cells for people with diabetes
  • embryonic stem cells can also produce nerve cells for paralysed people
  • stem cells in plants are found in the meristems
  • stem cells can be used to make clones of whole plants quickly & cheaply
  • stem cells can also be used by farmers to grow crops with their desired features
  • Diffusion is the net-movement of particles from a region of higher concentration to a region of lower concentration
  • diffusion only occurs in solutions & gases
  • the bigger the concentration gradient, the faster the rate of diffusion
  • the larger the surface area of the membrane, the faster the rate of diffusion
  • Osmosis is the net-movement of water particles from a region of higher concentration to a region of lower concentration, through a partially permeable membrane.
  • a partially permeable membrane is a membrane with very small holes in it
  • active transport is the movement of substances from a region of lower concentration to a region of higher concentration, against a concentration gradient