Keywords for Cell Structure
Term
Definition
Magnification formula
Magnification = power of objective lens x power of eyepiece lens
Stage
The stage holds the slide which contains the specimen to be viewed
Diaphragm
The diaphragm controls the amount of light reaching the specimen
Fine focus
The fine focus sharpens the image under high and low power. It moves the stage by small amounts
Coarse focus
The coarse focus focuses the image under low power
Objective lens
A lens attached to the nosepiece which magnifies the specimen
Eyepiece lens
The eyepiece lens magnifies the image, usually 10 times
Magnification formula
Magnification = power of objective lens x power of eyepiece lens
Compound Microscope
A microscope that uses two lenses for magnification
Protoplasm
The Protoplasm is all the living parts of the cell
Function of the cell wall
The cell wall gives strength to the cell
Function of the vacuole
The vacuole gives the cell strength and stores water, salts and sugars
Cytoplasm
The cytoplasm is the jelly like material outside the nucleus
Ultrastructure of the cell
Cell ultrastructure is the fine details of the cell that can be seen using an electron microscope
Cell membrane
The cell membrane is a thin membrane around the cell that is made of phospholipids and proteins
Function of cell membrane
Cell membranes retain the cell contents and they control what goes in and out of the cell
Nucleus
The nucleus is the control centre of the cell
Chromatin
Chromatin consists of DNA and proteins that makes up a chromosome when it is not dividing
Nucleolus
The nucleolus is an area of the nucleus where ribosomes are made
Mitochondria
The mitochondria supply energy to the cell. Respiration occurs here
Chloroplasts
Chloroplasts are only found in plant cells. They are the green structure where photosynthesis takes
place.
Cell Walls
Cell walls are only found in plant cells. They are made of cellulose.
Function of cell wall
The function of the cell wall is to give strength and support to the plant cell. They are fully permeable.
Ribosomes
Ribosomes are tiny structures which are made of DNA and protein. Their function is to make proteins.
Prokaryotic Cells
Prokaryotic Cells do not have a nucleus or membrane bound organelles
Eukaryotic Cells
Eukaryotic Cells have a nucleus and cell organelles
Electron Microscope
A microscope that achieves much greater magnification than a light microscope as it uses a parallel
beam of electrons to illuminate the object instead of a beam of light