B1

• what is eukaryotes?

  made from complex cells called eukaryotic cells (e.g. all animals and plants)
• what are prokaryotes


  smaller and simpler cells called prokaryotic cells (e.g. bacteria)
• what is a nucleus

  contains DNA in the form of chromosomes that controls the cells activities
• what is cytoplasm

  gel like substance where most of the chemical reactions happen
• what is mitochondria

  these are the site of cellular respiration and contain the enzymes needed for the reactions involved
• what are ribosomes

  these are where proteins are made in the cell
• what is cell membrance

  holds the cell together and controls what goes in and out by providing a selective barrier. they also contain receptor molecules that are used for cell communication
• what extra cell structures does a plant cell have

  cell wall, chloroplasts and vacuole
• what is a cell wall

  made of cellulose, gives support for the cell
• what are chloroplasts

  where photosynthesis occurs, they contain a green substance called chlorophyll
• in a bacterial cell what cell structures does it contain that eukaryotic cells dont have

  slime capsule, plasmids and pili
• what is a vacuole

  helps keep the cell rigid, they are full of cell sap
• what is a slime capsule

  an outer convering that protects the cell from drying out and poisionus substances
• what is pili

  hair like structures to enable the cell to attatch to structures
• what are plasmids

  circular piece of DNA used to store genes which are not involved in reproduction
• what is the nucleoid region

  area of the cytoplasm that contains the single bacterial DNA molecule
• what is resolution

  how well a microscope distinguishes between two points that are close together
• what do electron microscopes help us to see

  smaller things in more detail (e.g. internal structure of mitochondria)
• what can light microscopes help us see

  nuclei and chloroplasts
• what are transmission electron microscopes

  a higher magnification and resolution than light microscopes but they are not portable, they are expensive and a complicated process to prepare specimens. but they cant be used to look at living tissue
• what is magnification

  how many times bigger the image is than its real size
• what is the equation for total magnification

  eyepiece lens magnification x objective lens magnification
• what is the equation for magnification

  image size/real size
• what does DNA contains

  all organisms genetic material - the chemical instructions it needs to grow and develop
• what is DNA arranged into

  chromosomes
• what are chromosomes

  long molecules of coiled up DNA. The DNA is divided up into short sections called genes
• what is a double helix

  a double stranded spiral. each of the two DNA strands is made up of lots of nucleotides joined together in a long chain
• what does each nucleotide contain

  a base. DNA has 4 of these
• what are the bases

  • A - Adenine
  • C - Cytosine
  • G - Guanine
  • T - Thymine
• what bases always pair up with eachother

  A + T

  C + G
• what 3 things do nucleotide contain

  1. sugar
  2. phosphate group
  3. base
• true or false DNA is a polymer

  true
• what are polymers

  large, complex molecules composed of long chains of monomers
• what are monomers

  small, basic molecular units
• how are proteins made

  reading the code in DNA
• what does DNA control in protein photosynthesis

  the production of proteins
• what is a section of DNA that codes for a particular protein called

  a gene
• what are proteins made up of

  chains of molecules called amino acids
• what is amino acids coded by

  a sequence of 3 bases (a triplet code)
• where are proteins synthesised

  ribosomes