sb1

• when was the first microscope using 2 lenses produced

  invented by robert hooke in 1665
• antonie Van Leeuwenhoek managed to make better lensess than robert hookes this meant he created a microscope that had higher magnifications of up to..........

  230x
• over time the production of better lenses has meant that light microscopes can now magnify up to.........

  x1500 with resolutions of 0.0001mm
• when was the electron microscope crceated and how does it work

  invented in the 1930s and a beam of electrons pass through an object to produce an image (x2,000,000 magnification, 0.0000002mm resolution)
• what is the resolution

  the smallest distance between 2 points
• what does the magnification of a microscope equal

  magnification of microscope = eyepeice magnification x lens magnification
• standard form for pico,nano,micro and millimeters

  pico10^12, nano 10^9, micro 10^6, milli10^3
• What does eukaryotic mean?

  cell with a nucleus (plants and animals)
• What does prokaryotic mean?

  no nucleus or organelles
• what is the subcellular structure of an animal cell

  nucleus,cell membrane,mitcondria,ribosomes
• what is a nucleus

  controlls the cell and contains genetic info
• what is the cell membrane

  controls what leaves and enters the cell,seperates one cell from another
• what are the mitcondria

  the site of aerobic respiration
• ribosomes are..

  the site of proteinsynthesis
• what is proteinsynthesis

  the process of making proteins
• what is the subcellular structure of a plant cell

  the same as an animal cell but also cell wall,chloroplasts and vacuole
• what is the cell wall

  made of cellulose and supports the cell
• what are chloroplasts

  contains chlorophyll that traps the suns energy for photosynthesis
• what is the vacuole

  stores cell sap and keeps the cell firm and rigid
• what do sperm cells contain

  acrosome, haploid nucleus, mitochondria,tail(flagellum)
• what is the use of the acrosome

  a small vacuole that contains an enzyme that breaks down the egg cell jelly coat
• what is the use of a haploid nucleus

  one copy of each chromosone
• what is the use of the mitcondria

  the site of aerobic respiration
• what is the use of the tail/flagellum

  movement (moves in a propeller like movement)
• what do egg cells contain

  nutrients in the cytoplasm, haploid nucleus and changes in the cell membrane after fertilisation
• why are there nutrients in the cytoplasm

  to provide the embryo with nutrients for growth
• changes in the cell membrane after fertilisation

  becomes hard after fertilisation to stop more sperm getting in
• what do cilliated epithelial cells contain

  cillia
• what is the use of cillia

  they are hair like structures that help move along egg cells
• what do bacteria contain

  chromosnal DNA, plasmid DNA, cell membrane, ribosomes, flagella(not on all bacteria)
• what is the use of chromosonal DNA

  controls the cells activities
• whata is the use of plasmid DNA

  ring of DNA controls some cell activities
• what is an enzyme

  a protein that catalyses biological
• what does a catalyst do

  speeds up a chemical reaction without being used up in a reaction
• what can enzymes do

  can synthesise polymers (e.g. proteins) from monomers (e.g. amino acids)
• what are proteins made up of

  amino acids
• what is starch made up of

  glucose
• what are lipids made up of

  fatty acids and glycerol
• where is amylase found and the reaction catalysed

  found in the saliva and small intestine. breaks down starch to small sugars such as maltose.
• where is catalase found and the reaction catalysed

  most cells, but especially liver cells. breaking down hydrogen peroxide made in many cell reactions to water and oxygen