B1 - Cell Structure and transport Flashcards
How does a light microscope work?
Light microscopes use a beam of light to form an image
How does an electron microscope work?
Electron microscopes use a beam of electrons to form an image
Give a pro and con of light microscopes:
Pro
Relatively cheap
Can be used almost anywhere
Can produce colour images
Small - takes up less room
Con
Low resolving power
Give a pro and con of electron microscopes:
Pro
Higher resolution
Higher magnification
Can see tiny sub-cellular structures
Con
Very expensive
Must be kept in certain conditions
Large - take up a lot of space
Only produces black and white images
What are the two types of eukaryotic cell?
Animal and plant
What type of cell are bacteria?
Prokaryotic
Where is DNA found in animal and plant cells?
Nucleus
What is the function of the cell membrane?
Controls movement of substances in and out of the cell
What is the function of mitochondria?
Site of aerobic cellular respiration to transfer energy for the cell
What is the function of chloroplasts?
The organelles in which photosynthesis takes place. Contains chlorophyll to absorb light energy for photosynthesis
What is the function of ribosomes?
Where protein synthesis takes place, making all the proteins needed in the cell
What is the function of the cell wall?
Made of cellulose
Strengthens and supports the cell
What is the structure of the main genetic material in a prokaryotic cell?
Single loop of DNA
What is the function of a red blood cell?
Carries oxygen around the body
Give 2 adaptations of a red blood cell:
No nucleus
Contains a red pigment called haemoglobin
Has a bi-concave disc shape
What is the function of a nerve cell?
Carries electrical impulses around the body
Give 2 adaptations of a nerve cell:
Branched endings
Myelin sheath insulates the axon
What is the function of a sperm cell?
Fertilises an ovum (egg)