Bio paper 1

• Cytoplasm


  Chemical reaction takes place
• Cell membrane 


  Controls what enters and leaves the cell
• Mitochondria 


  Aerobic respiration takes place
• Ribosomes


  Sites of protein synthesis
• Chloroplast


  Contains chlorophyll

  sites of photosynthesis
• Cell wall


  Cellulose

  strengthen the cell
• Permanent vacuole


  Cell sap to give shape
• Differentiation 


  When cells become specialised to do a certain job
• How are sperm cells specialised


  Long tail

  streamline

  mitochondria for energy to swim
• Where is the genetic material In prokaryotic cells


  Single loop of dna
• Parts of prokaryotic cells


  Single loop of dna

  cell membrane

  cell wall

  cytoplasm
• Enzymes in sperm cell


  Digest their way through outer layer of the ovum
• Purpose of nerve cells

  Send electricle impulses around the body
• Long axon


  Carries electricle impulses from one part of the body to another
• Myelin


  Insulates the axon

  speeds up transmossion of nerve impulses
• Synapses 


  End of axon

  junctions allow impulses to pass from one nerve cell to another
• Dendrites


  Increase surface area so another nerve cell can connect easier
• how are muscle cells specialised

  Can contract
• How do muscle cells shorten


  Contain protein fibre

  packed with mitochondria to provide energy for muscle contraction

  work together to form muscle tissue
• Muscle tissue


  Contracts to move whatever it’s attached to
• Glandular


  Produce enzymes and hormones
• Glands 


  Pancreas and salivary

  produce digestive juices
• Stomach and small intestine

  Digest food
• Liver


  Produces bile
• Small intestine


  Absorbs insoluble food molecules
• Large intestine 


  Absorbs water from undigested food

  faeces
• Lock and key


  Enzymes have a specific shape so fits onto substance involved in reaction
• What fits in the active site in the lock and key

  Substrate
• Enzymes


  Large protein made up of chains of amino acids
• Denatured enzymes


  Too hot bonds holding enzymes together break

  changes shape of active site

  substrate won’t fit
• Enzymes ph


  Too high or too low interferes with bonds holding enzymes together

  changes shape of active site and denatures enzyme
• enzymes optimum ph


  Work best at

  mostly neutral 7
• Enzymes in digestion


  Produced by cells

  released into gut to mix with food
• Amylase


  Carbohydrates

  break down starch
• Amylase is made


  Salivary glands

  pancreas

  small intestine
• Protease 


  Converts proteins to amino acids
• Protease made in


  Stomach

  pancreas

  small intestine
• Lipases


  Converts lipids into glycerol and fatty acids
• Lipases made 


  Pancreas

  small intestine
• Benedict’s test for sugar


  Prepaid food sample and water bath (75*)

  add 10 drops of solution to test tube

  leave for five mins

  should change to green yellow or red