B1 - Cell Biology

Cards (40)

  • Diffusion
    Particles/ molecules move from a high concentration, to a low concentration until an equilibrium is reached. No energy required.
  • Osmosis
    Movement of water particles from a high concentration to a low concentration across a partially permeable membrane.
  • Factors speeding up diffusion & osmosis

    - Higher temperature (particles gain kinetic energy)
    - Thinner membranes (shorter diffusion distance)
    - Higher concentration gradient (takes longer for an equilibrium to be reached)
  • Water potential
    Water concentration
  • Active transport
    Particles move from a low concentration to a high concentration and requires energy.
  • Diffusion (Examples)
    - In the lungs (Carbon Dioxide, oxygen, glucose)
    - Carbon dioxide into plants via stomata
  • Osmosis (Examples)
    - Distilled water entering a cell
    - Small intestine
  • Active transport (Examples)
    - Root hair cells (mineral ions from a low concentration in soil to a high concentration in root hair cell)
    - Small intestine (glucose and amino acids from low concentration in small intestine to a high concentration in the blood using energy)
  • Light microscope
    - Low magnification
    - Low resolution
    - Living sample
    - Image in colour (from dye), 2D
    - Image can be blurry
    - Cheaper
    - Used in schools
  • Electron microsope
    - High magnification
    - High resolution
    - Dead sample
    - Image in black & white
    - Pass electrons through sample
    - Expensive
    - Uses a vacuum
  • Microscope parts
    - Eye piece
    - Arm
    - Objective lenses
    - Stage
    - Focus
    - Light
    - Base
  • Magnification
    How much bigger an object appears to be than it really is when viewed through a microscope. (Image/ actual)
  • Resolution
    The smallest distance that can be seen between two points. (The smaller the distance, the higher the resolving power)
  • Metres order
    Kilometres, metres, millimetres, micrometres, nanometres
  • Nucleus
    Controls the cell's activities and contains DNA
  • Mitochondria
    Site of respiration (Release energy through respiration)
  • Cytoplasm
    Site of chemical reactions
  • Cell membrane (inside)
    Allows chemicals in and out of the cell
  • Cell wall
    Strength and support for the cell
  • Ribosomes
    Make proteins
  • Vacuole
    Stores cell sap (cell food) and keeps cell turgid (full)
  • Chloroplasts
    Site of photosynthesis, contain chlorophyll
  • Eukaryotic cells
    - Have a nucleus
    - Bigger
    - Mitochondria
    Plants, animals, yeast
  • Prokaryotic cells
    - No nucleus
    - Smaller
    - No mitochondria
    Bacteria
  • Sperm cell
    Long tail, pointy head - Help swim and dig into the egg
  • Muscle cell
    Overlapping edges - Allows muscles to contract, move
  • Nerve cell
    Many branches - Carry more nerve impulses at a time
  • Root hair cell
    Elongated shape, tail - Increase surface area to absorb more water
  • Phloem
    Little cytoplasm, no nucleus - More room for sugars
  • Xylem
    Pits, lignin - Water can move between adjacent cells, stronger walls
  • Stem cell
    A cell that hasn't undergone differentiation (all cells start off like this)
  • Mitosis
    Cells divide to allow for growth, replace damaged cells (repair)
  • Production of new cells - Duplication
    DNA replicated so form two copies of the chromosomes. Increase number of mitochondria, ribosomes, etc.
  • Production of new cells - Mitosis
    One set of chromosomes is pulled to each side of the nucleus and then the nucleus splits into two.
  • Production of new cells - Cleaving
    Cytoplasm and cell membranes split and form two genetically identical cells.
  • Meristem tissue
    Plant stem cell
  • Therapeutic
    Relating to the treatment of a disease
  • Therapeutic cloning
    1 - Need two cells; one from the patient and a donated egg cell.
    2 - Remove nucleus from egg, skin cell and replace with patient's nucleus.
    3 - Electric shock is uses to stimulate cell division to develop into an embryo

    Used to treat cancer, diabetes, heart disease, infertility, regrow tissues, replace faulty organs
  • Animal stem cell - Embryonic
    Undifferentiated ( Allow them to develop into a foetus - fertilised egg cell)
  • Animal stem cell - Adult
    Differentiated (specialised), used to repair damaged tissues and replace dying cells, found in blood, skin, brain, heart, liver etc.