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• What happens during a CT scan?

  • The patient is given a radioactive tracer which allows different parts of the brain to show up. A CT scan is carried out, taking many different X-rays of the skull and brain from different angles and a computer puts all these images together to form a three dimensional image
• What do the cerebral hemispheres do?

  Voluntary movement, interpret sensory information and are responsible for learning and memory
• What does the medulla oblongata do?

  Regulates the heart beat and breathing
• What does the cerebellum control?


  Precise and smooth movement
• What are the three types of neurones?

  Sensory neurones, motor neurones and relay neurones
• What do sensory neurones do?

  Carry impulses to the central nervous system
• What do motor neurones do?

  Carry impulses to the central nervous system to the effector organs
• Where are relay neurones found?

  Only in the central nervous system
• What is the travelling or transmission of impulses called?

  Neurotransmission
• Where does neurotransmission take place?

  In neurones
• What are neurones?

  Nerve cells
• What is the process of the process through a receptor cell?

  Receptor cell, dendrite, dendron, axon
• What is the fatty layer surrounding dendrons and axons?

  Myelin shealth
• What does a myelin sheath do?

  Electrically insulates a neurone from neighbouring neurones which stops the signal losing energy and also makes an impulse ‘jump’ along the cell between the gaps in the myelin, speeding up transmission
• What is the process of the CNS?

  Sensory neurone, CNS, relay neurone (sometimes), motor neurone, reaction
• What test is used for protein?


  Biuret test, potassium hydroxide is mixed with a solution of the food. Two drops of copper sulfate solution are then added. If the pale blue solution turns purple, this indicates that protein is the the food
• How are fats and oils (lipids) tested for?

  The ethanol emulsion test. THe food is mixed with ethanol and sharken. Some of that mixture i then poured into water and shaken again. Fats and oils dissolved in the ethanol float to the surface, forming a cloudy emulsion, when the mixture is left to stand
• What arw the two stages of protein synthesis?

  Transcription, Translation
• What happens during transcription?

  Transcription:

  • A section of DNA is unwound and the two strands separate
  • The enzyme RNA polymerase binds to the non-coding DNA in front of the gene
  • Free complementary bases pair with the open bases on one DNA strand. The free nucleotides are joined together by the enzyme RNA polymerase to make a strand of complementary mRNA
  • The mRNA leaves through pores in the nucleus into the cytoplasm
• Translation

  1. mRNA attaches to ribosome

  2. Ribosome moves along mRNA reading one triplet of bases (codon) at a time

  3. tRNA molecules bring amino acids to ribosomes

  4. Complementary bases of tRNA pair with bases on the mRNA strand

  5. Amino acids that are close together are joined to make an amino acid chain (a polypeptide)

  6. tRNA is free to collect another amino acid

  7. Amino acids in a particular order fold into a specific protein

  8. One section of DNA codes for a specific protein
• What is a polypeptide?

  An amino acid chain
• Where does translation take place?

  In the cytoplasm when the mRNA strand attaches to a ribosome
• What is the reflex arc?

  The reflex arc is a neural pathway that allows for an automatic and rapid response to a stimulus, bypassing conscious thought.
• What is the process of the reflex arc?

  Stimulus, receptor, sensory neurone, relay neurone, motor neurone, response
• Relay neurone

  
• Motor neurone

  
• Sensory neurone

  
• Where are relay neurones found?

  Central nervous system
• Four I’s used to describe what the reflex arc is -

  Immediate

  Involuntary

  Innate

  Invariable
• What do reflexes do?

  Protect us from immediate harm
• What do the cornea and the lens do in the eye?


  Focus the light to form a sharp image on the retina
• WHat happens when the suspensory ligaments contract and the ciliary muscles relax?

  The lens becomes wider and the ligaments pull it thinner
• What happens when the suspensory ligaments relax and the ciliary muscles contract?

  Its diameter becomes smaller; the suspensory ligaments slacken causing the lens to go back to its normal thicker shape
• When does the pupil become smaller?

  When focusing on nearer objects and in bright light
• When does the pupil become larger?

  When focusing on a distant object or in dim light
• What are present in a bacterial cell?

  Chromosonal DNA

  Plasmid DNa

  Flagellum (not always present)

  CEll membrane

  Cell wall
• What are present in an animal cell?

  Cytoplasm

  Nucleus

  Ribosome

  mitochondria

  Cell membrane
• What are present in a plant cell?

  Cytoplasm, nucleus, vacuole, cell wall, cell membrane, mitochondria and chloroplasts
• What is the function of ribosomes?

  PROTEIN SYNTHESIS
• WHAT IS THE FUNCTION OF THE VACUOLE?

  Fill with cell sap to keep the cell swollen