biology

• what function of does the motor neurone do 


  carry nerve impulses away from the central nervous system
• what is evolution 


  gradual change in the characteristics of species over time
• cytokinesis is..


  the cytoplasm and cell membrane dividing to form 2 daughter cells
• order of the cell cycle

  interphase

  prophase

  metaphase

  anaphase

  telophase

  cytokinesis
• what is natural selection 


  variation of some individual make them better at copying with change than others and more likely to survive
• metaphase is 


  chromosome line up at the centre of the cell
• anaphase is 


  each chromosome split in half

  each half is exactly the same as the other half

  2 halves are pulled to opposite ends of the cell
• telophase is

  membrane form around each new set of chromosomes
• 2 strands coiled together are

  a double helix
• nucleotide is made up of

  a sugar phosphate group and one base
• DNA stands are 


  polymers
• what is it called when the cell divides

  mitosis
• advantages of reflex arc

  quick, automatic response to stimuli
• 2 types of DNA found in bacterial cells 


  plasmid DNA

  chromosonal DNA
• what do receptor cells do 


  detect change in environment
• what do synapses do to the speed of neurotransmissions

  rapidly increase
• 3 factors that affect enzyme activity 


  PH

  tempreture

  concentration
• why do we grind the fruit 


  breaks cell apart from each over and breaks down cell wall
• why do we use detergent 


  breaks down cell membranes and membranes around nuclei
• DNA extraction: why do we use the salt 


  makes the DNA clump together
• investigating cells: what is the coverslip used for 


  keep specimen in place
• investigating enzyme action:

  when you add iodine near the end it, it should be yellow in colour why is this?

  the enzyme has broken down all the stratch present
• investigation enzyme action:

  why does the temp have to be optimum 37

  starch won’t break down at a temperature that is to high or low as the enzymes won’t work at those tempretures
• investigating enzyme action:

  if a temperature is to high or low the active site won’t fit the substrate as it denatures
• physical barriers humans

  the body has skin

  saliva- protect the thinner surface of the body
• chemical barriars human


  hydrochloric acid to kill pathogens
• selective breeding is when we choose the best individuals from one generation to mate together so that their offspring will have desirable characteristics
• 6 MARKER!

  pathogens enter the body, white blood cells identify antigens, phagocytes engulf and digest pathogens, lymphocytes with antibodies that perfectly fit with antigen are activated, activated lymphocytes divide rapidly, some lymphocytes produce lots of antibodies and memory lymphocytes stay in the body
• some mutations change an organism phenotype
• a change in bases of a gene creates a genetic variation/ mutation
• what is the function of the chloroplast


  contains chlorophyll-where photosynthesis takes place
• function of the vacole 


  contains cell sap
• function of cell wall


  protect and strengthen the cell
• function of ribsome


  make protein
• function of mitochondria 


  produces energy
• function of cell membrane


  controls what enters and exits cell
• function of nucleus 


  contains DNA
• label 8 organelles of a plant cell


  cytoplasm

  mitochondria

  nucleus

  ribsome

  chloroplast

  cell membrane

  cell wall

  vacole
• function of cytoplasm


  where chemical reactions take place
• why are light microscopes better than electron


  cheaper

  can see organisms