B1

• eukaryotic cell


  contain their genetic material (dna) enclosed in a nucleus
• prokaryotic cells


  in these cells, genetic material (dna) is not enclosed in a nucleus, and are much more smaller than eukaryotic cells.
• eukaryotes contain:

  • a cell membrane
  • a nucleus
  • a cytoplasm
  • genetic material (dna)
• prokaryotes contain:

  • a cell membrane
  • a cell wall
  • a cytoplasm
  • genetic material (loop of dna and plasmids)
• centi(cm)

  1/100th
• milli(mm)

  1/1000th
• micro(μm)

  1/1,000,000th
• nano(nm)

  1/1,000,000,000th
• order of magnitude

  usually 10x bigger than the one before
• 10x

  one order of magnitude
• 100x

  two orders of magnitude
• 1000x

  three orders of magnitude
• example question:

  A fox is 40 cm long, a tick living on a fox is 0.4cm long. How many orders of magnitude is the fox longer than the tick?

  40/0.4=100

  =two orders of magnitude
• label the numbers:

  • 1=nucleus
  • 2=cytoplasm
  • 3=cell membrane
  • 4=mitochondria
  • 5=ribosomes

  
• animal cell


  they are eukaryotic

  their genetic material is enclosed in a nucleus
• nucleus

  enclose genetic material
• cytoplasm

  watery solution where chemical reactions take place
• cell membrane 


  controls the molecules that can enter and leave the cell
• mitochondria 


  where aerobic respiration takes space
• ribosomes


  sites of protein synthesis
• plant cells :

  • can use light to undergo photosynthesis
  • the shapes can change
  • genetic material is enclosed in a nucleus
  • eukaryotic
• label the numbers:

  6=chloroplasts

  7=cell wall

  8=permanent vacuole

  
• cell wall

  made from cellulose

  this strengthens the cell
• chloroplast

  contains chlorophyll and are the sites of photosynthesis
• permanent vacuole 


  filled with a fluid called cell sap

  the vacuole helps give the plant cell its shape
• animal cell specialisation

  • most are specialised
  • they have adaptations which help them to carry out their particular function
  • when cells become specialised scientists call that differentiation
• sperm cell

  their job is to join with an ovum which creates fertilisation
• label the numbers

  1=cytoplasm

  2=ribosomes

  3=nucleus

  4=mitochondria

  5=cell membrane

  
• sperm cells contain:

  • enzymes
  • a nucleus
  • a tail
  • mitochondria
• label the numbers

  1=nucleus

  2=tail

  3=enzymes

  4=mitochondria

  
• nucleus (sperm cell)


  genetic information is stored here

  sperm cells only contain half the genetic information of a normal adult cell
• tail


  allows them to swim to the ovum(egg cell)

  streamlined to make this easier
• mitochondria (sperm cell)


  packed full of it

  provides energy needed for swimming
• enzymes


  allow them to digest their way through the outer layer of the ovum
• nerve cell


  their job is to send electrical impulses around the body
• nerve cells contain 


  • dendrites
  • an axon
  • myelin (sheath)
  • synapse
• label the numbers

  1=dendrites

  2=axon

  3=synapse

  4=myelin(sheath)

  
• axon


  carries out the electrical impulses from one part of the body to the other
• myelin (sheath)


  insulates the axon and speeds up the transmission of nerve impulses
• synpase


  junction which allows the impulses to pass from one nerve cell to another