B1 Cell structure and transport Flashcards
1 kilometre (km) in metres (m)
1000 metres (m)
1 metre (m) in centimetres (cm)
100 centimetres (cm)
1 centimetre (cm) in milimetres (mm)
10 milimetres (mm)
1 milimetre (mm) in micrometres (µm)
1000 micrometres (µm)
1 micrometre (µm) in nanometres (nm)
1000 nanometres (nm)
How do you calculate the size of an object
magnification = size of image / size of real image
Label a light microscope
What are the two types of microscope
light microscope
electron microscope
What are the benefits of the light microscope
cheaper
used almost anywhere
can magnify live specimins
What are the benefits of the electron microscope
Can view small organelles
Higher magnification and resolution
can create 3D images
What are the disadvantages of the electron microscope
Large
Very expensive
kept at special temperature, pressure and humidity
What is resolution?
The ability to distinguish between two separate points and it is the resolving power of a microscope that affects how much detail it can show
What is the resolving power of a light microscope
200nm or x 2 000 000
What is the resolving power of an electron microscope
0.2nm or x 2 000
What is the function of the nucleus
controls all the activities of the cell and is surrounded by the nuclear membrane. It contains the genes on the chromosomes that carry the instructions for making the proteins needed to build new cells or new organisms. the average diameter is around 10µm
What is the function of the cytoplasm
A liquid gel in which the organelles are suspended and where most of the chemical reactions needed for life to take place
What is the function of the cell membrane
Controls the passage of substances such as glucose and mineral ions into the cell. It also controls the movement of substances such as urea or hormones out of the cell.
What is the function of the mitochondria
Structures in the cytoplasm where aerobid respiration takes place, releasing energy for the cell. They are very small: 1-2µm in length and only 0.2-0.7µm in diameter
What is the function of the ribosomes
Where protein synthesis takes place, making all the proteins needed in the cell
Label an animal cell
Are plant cells bigger or smaller than animal cells
bigger
What organelle do all plant cells have that animal cells don’t
cell wall
What is the function of the cell wall
Made of cellulose that strengthens the cell and gives it support
What is the function of the chloroplast
They are green due to them containing a green substance (chlorophyll). chlorophyll absorbs light so the plant can make food by photosynthesis. each chloroplast is around 3-5µm long. Root cells do not have chloroplasts because they are underground and do no photosynthesise.
What is the function of the permanent vacuole
Its a space in the cytoplasm filled with cell sap. this is important for keeping the cells rigid to support the plant
label a plant cell
Give examples of eukaryotic cells
Animal, Plant, fungi, protista
What organelles do Eukaryotic cells have?
cell membrane, cytoplasm, genetic material enclosed in nucleus
What is genetic material
a chemical called DNA and this forms structures called chromosomes that are contained within the nucleus.
What is bacteria
sing;e-celled living organisms
Give an example of Prokaryotes
bacteria
How big is a Prokaryote?
0.2-2.0µm
How much smaller are prokaryotes than eukeryotes
1-2 orders of magnitude smaller
What organelles do bacteria contain?
cytoplasm, cell membrane, cell wall,
Where is DNA in prokaryote
singe DNA loop found free in the cytoplasm or extra small rings of DNA/plasmids