y9 microscope-cells revision Flashcards
Whats the function of a microscope?
To magnify small objects
What does a light microscope use to magnify specimens?
Light.
What does a electron microscope use to magnify specimens?
electrons pass through the specimen
where/apperance is the stage and what does it do?
its the square thing that holds the specimen
where/apperance is the arm and what does it do?
the long thing which holds it all together.
where/apperance is the eyepeice lens and what does it do?
what u look into and it magnfies the specimen
Where is the diaphragm and function
under stage. adjusts light intensity when turned
a.what is the glass called that the specimin sits on?
b. what do liquid do you put ontop of the specimin?
c. what do you put ontop (square)?
slide.
stain.
coverslip.
what is magnification. fully accurate.
How many times bigger an image is compared to the object.
what is resolving power?
The ability to distinguish between two points on a object.
In which microscope do specimin have to be DEAD
electron
- Disadvantages of light microscope.
1&2. magnification AND resolution power is not high enough to produce a image with great enough detail and intricate cell sctructure.
- Limited contrast can make it hard to see different parts of a specimen without a stain.
whats the difference between coarse focus and fine focus
Coarse Focus: Moves the stage up and down quickly for initial focusing.
Fine Focus: Makes small adjustments for precise clarity after using coarse focus.
which objective lens is used first,
- 4x (red) depending
2.10x (yellow) depending
- 40x (blue) depending
how many mm in cm
10
you divide by 1000 each times when going from…
(nm)nanometre to
(µm)micrometre to
(mm)millimetre to
(m)metre
you times by 1000 each times when going from…
(m)metre to
(mm)millimetre to
(µm)micrometre to
(nm)nanometre
how to find image, size of object or image size?
use I / AxM
how to turn mm into cm?
x10
how to turn mm into m
divide 1000
how to turn mm into nm
x1000
x1000
how to turn cm into µm
x10 = mm
x1000 = µm
how to turn nm into m
divide 1000
divide 1000
divide 1000
how to find magnification. (not i am)
eyepeice lens x objective lens
step 1 for onion skin required practical
collect a sample of the cell you want to observe
step 2 for onion skin required practical
Remove the inner skin of a layer of onion using forceps.
step 3 for onion skin required practical
Place the thin slice onto a clean glass slide. Use your forceps to keep the onion skin flat on the glass slide.
step 4 for onion skin required practical
Using a pipette, add one or two drops of dilute iodine solution on top
step 5 for onion skin required practical
Hold the coverslip by its side and lay one edge of the cover slip onto the microscope slide
step 6 for onion skin required practical
- Lower the cover slip slowly so that the liquid spreads out. (using the mounted needle)
how many organells are there (i shld know)
8.
what type of cell has 5 of the organells
animal
function of cell membrane
Controls the movement of substances in and out of the cell.
function of the nucelus
Contains DNA and controls the activities of the cell.
whats the function of cytoplasm
jelly like substance
Where chemical reactions take place.
whats the function of mitochondria
where respiration takes place
whats the function of ribosomes
where protein-synthesis takes place
whats the function of cell wall
Made of cellulose, this supports the cell.
whats the function of chloroplasts
Contain chlorophyll, which absorbs light for photosynthesis.
whats the function of permanent vacuole
Filled with cell sap, helping to keep the cell rigid.
