B1 Flashcards
How many meters in a km?
1000m
How many cm in a m?
100cm
How many mm in a cm?
10mm
How many μm (micrometers) in a mm?
1000μm
How many nm (nanometers) in a μm (micrometer)
1000nm
What is the average size of a plant cell?
10-100μm
What is the average size of an animal cell?
10-30μm
List parts of a microscope?
Eyepiece
Arm
Clips
Course Focusing Wheel
Fine Focusing Wheel
Nose Piece
Objective Lens
Stage
Condenser
Light
Base
How to focus a microscope?
Turn course focusing wheel until cells come into focus, then turn fine focusing wheel until you can clearly see the cells
What is the Image?
What you see when you look down the microscope
What is the Object?
The real sample you’re looking at
What is Magnification?
Enlarging the apparent size of the object, not its physical size
What magnification does the eyepiece already have?
x10
How to find the magnification?
Whichever magnification the objective lens has (x4, x10 or x40) times by 10 as the eyepiece already has a x10 magnification.
The IAM triangle
I A Image = Actual Size ÷ Magnification
M
What is Resolution?
The ability to distinguish 2 points/objects that are very close to each other
What does a high resolution mean?
You can see more detail
What does low resolution mean?
You can see less detail
How do light microscopes work?
What are their magnification?
Resolution?
Image?
Samples?
Light passes through cells then reflects through lens. Lens bends light towards your eye which magnifies it.
3 lenses: x4, x10, x40. Eyepiece has magnification of x10
Low, details are blurry
In colour
Dead or alive
How do electron microscopes work?
Magnification?
Resolution?
Image?
Samples?
Beam of light replaced by ray of electrons. Lenses replaced by coil shaped electromagnets.
x1000000
High, details are clear
Shows as a micrograph (photo.) In black and white
Have to be held in a vacuum for electrons to pass through easier so samples are dead
List plant cell organelles and their functions?
Vacuole: Chemical store, keeps cell rigid and stores cell sap
Cell Membrane: Regulates the transport of materials entering and exiting the cell
Cellulose Cell Wall: Gives strength and structure to the cell
Nucleus: Stores genetic information and controls the cell
Ribosomes: Where proteinsynthesis occurs
Chloroplasts: Absorbs light so photosynthesis can happen. Contains chlorophyll
Mitochondria: Releases energy through respiration
Cytoplasm: Where other organelles are held and where chemical reactions occur