Unit one

• Cellulose


  Structural carbohydrate that makes up plant cell walls
• Ribosomes


  Organelle where proteins are made
• Micrometres


  Unit used to measure cell size
• Cell membrane


  Controls the entry and exit of substances in a cell
• Cytoplasm


  Site of chemical reactions
• Mitochondria


  Site of Aerobic respiration
• Vacuole


  Organelle filled with cell sap in plant cells
• Chloroplast


  Site of photosynthesis
• Cell wall


  Provides structure and support, preventing a cell from bursting
• Nucleus


  Controls cells activities
• Plasmid


  Single, circular loop of DNA found in a bacterial cell instead of a nucleus
• Cells that contain a nucleus

  • Animal
  • Plant
  • Fungal
• Cells that contain a cell wall

  • Plant
  • Fungal
  • Bacterial
• Cells that contain mitochondria

  • Animal
  • Plant
  • Fungal
• Structures found in all cells

  • Cell membrane
  • Ribosomes
  • Cytoplasm
• Cells that contain a vacuole

  • Plant
  • Fungal
• The only cells that can contain chloroplasts are plant cells
• Diffusion


  Movement of molecules from a higher to lower concentration
• Osmosis


  Movement of water molecules from a higher to a lower water concentration
• Passive transport


  Diffusion and osmosis that do not require energy
• Concentration gradient


  Difference in concentration
• Active transport


  Movement of molecules and ions from lower to higher concentration against the concentration gradient, requiring energy
• Plasma membrane


  Made up of proteins and phospholipids
• Selectively permeable


  Cell membrane only lets some molecules through and not others
• Turgid


  What happens to a plant cell when placed in pure water
• Plasmolysed


  What happens to a plant cell when placed in strong sugar solution
• Bursts


  What happens to an animal cell when placed in pure water
• Shrinks


  What happens to an animal cell when placed in strong sugar solution
• DNA


  Double stranded helix
• Complementary base pairs


  Adenine-Thymine and Cytosine-Guanine
• Amino acids


  What proteins are made of
• mRNA


  Molecule that carries a copy of the DNA code from the nucleus to the ribosome
• Ribosome


  Organelle that is the site of protein synthesis
• Nucleus


  Where mRNA is synthesised
• Chromosomes


  Thread-like structures made of DNA
• Proteins


  Chemicals that the information carried in DNA is used to make
• Gene


  Part of DNA that codes for a protein
• Sequence of bases


  Determines the order of amino acids and thus the structure and function of a protein
• Catalase

  Enzyme that breaks down hydrogen peroxide into oxygen and water
• Denatured

  What happens to an enzyme when it is exposed to high temperatures