B1 - Cell structure and transport
Light microscopes
Magnification = size of image / size of real object
Use a beam of light to form an image.
Can magnify objects up to 2000 times.
Can be used to view living objects.
Are relatively cheap and easy to carry around.
Electron microscopes
Use a beam of electrons to form an image.
Can magnify objects up to 2,000,000 times.
Cannot be used for living objects.
Are very expensive and need to be kept in special conditions.
1.2
Resolving power of 0.2nm
Resolving power of 200nm
Animal features that are common to all cells are a nucleus, cytoplasm, cell membrane, mitochondria, and ribosomes.
Plant and algal cells contain all the structures as the animal cell, and they also have cellulose cell wall.
Many plant cells also contain chloroplasts and a permanent and a permanent vacuole filled with sap.
Cells - structure and function
Animal
Plants
Nucleus control the cells activity's
Cytoplasm - liquid gel where organelles are suspended, chemical reactions take place.
Cell membrane - controls movement of substances, glucose and mineral ions to the cell - urea and hormones out of cell.
Mitochondria - energy is transferred in aerobic respiration.
Ribosomes - protein synthesis takes place.
Cell wall - made of cellulose
Chloroplasts - contain chlorophyll for photosynthesis - chloroplasts absorb light to make food.
Permanent vacuole - contains cells sap - keeps cell rigid & supports plant.
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