Bio 1

• Conversion table


  m = 10^0

  mm = 10^-3

  /mm = 10^-6

  nm = 10 ^-9

  pm = 10^-12
• Food tests


  Starch = iodine (blue/black if present)

  Reducing sugars (not sucrose) = benedicts solution (blue to cloudy orange/brick red when heated if present)

  Protein = buiret [potassium hydroxide and copper sulfate] (mauve/purple if present)

  Lipids = emulsion test [ethanol and water] (cloudy/milky white of present)
• Mitosis


  Interphase - NOT MITOSIS. DNA copied

  Prophase - DNA gets short and fat. Membranes dissappear

  Metaphase - chromosomes line up in the middle, attached to spindles

  Anaphase - spindles pull chromosomes to opposite sides of cell

  Telephase - membranes reform

  Cytokenesis - daughter cells fully form
• The brain


  2 cerebral hemispheres (cerebral cortex) folded for high surface area. Connected by corpus callosum

  Includes: frontal lobe - thinking, emotion, personality, motor cortex

  Temperal lobe - sound, hearing, speech, memory

  Occipital lobe - vision, shape, colour, perspective

  Parietal lobe - memory, movement

  Medulla oblongata - controls base functions like heartbeat, breathing, temp. etc.

  Cerebellum - base of brain, pressure, balance

  Spinal cord - made of nerves, connects brain to nervous system  
• Cones

  Sensitive to colour of light. Processed in occipital lobe. Works best in brighter light
• Rods

  Light intensity, works well in dim light
• Pupil

  Where light enters. Controlled by iris to protect retina (receptor cells) from bright light
• Cornea

  Focuses on clear point in retina
• Lens

  Fine tunes focusing
• Ciliary muscles

  Controls lens (fatter - near, thinner - farther)
• Short sightedness

  • Eye is too long
• Long sightedness

  • Eye is too short
• Correcting short/long sightedness

  1. Glasses

  2. Laser surgery
• Cataracts

  • Cloudy protein in lens. Can be corrected through lens replacement
• Colour blindness

  • Cones don't work properly. Red/green (green cones dont work properly) most common. Most common in men. Can't be corrected
• Pros and cons of asexual reproduction

  Pros

  Lack of need for a mate.

  Rapid reproduction

  Less energy needed

  Cons

  No variation (wiped out easier)

  Harder for species to adapt 
• Pros and cons of sexual reproduction

  Pros

  Variation

  High evolutionary change

  Helps adaptation

  Cons

  Need to find a mate

  Energy required
• Lytic pathway 


  Virus takes control of host, reproduces and bursts out, killing the host.

  1. Synthesisers protein to break down hosts DNA to take over machinery
  2. Use machinery to synthesise proteins for production of new virus.
  3. Causes virus to burst out of host cell in process of lysis, killing the cell.
  4. Repeats with other cells 
• Lysogenic pathway


  Virus incorporates its DNA into host DNA to replicate without killing

  1. Virus attaches to surface of host and penetrates it
  2. Injects DNA into hosts cytoplasm
  3. Cell replicates and virus DNA copies with it
  4. Under conditions, viral DNA undergoes induction. Cycle turns lytic.