Cell structure

Question 1

Give 3 properties of light microscope

Answer 1

.uses beam of light to form images
.Can magnify up to 400 times
. Cam be used to view living objects

Question 1

Give 3 properties of an electron microscopy

Answer 1

.uses beam of electrons to form images
.Can magnify up to 2 000 000 times
.Cannot be used on living objects

Question 2

Difference between transmission and scanning electron microscope

Answer 2

Transmission = 2D but higher magnification 
Scanning = 3D but lower magnification

Question 3

What is the resolving power of a light microscope in comparison to a transmission electron microscope

Answer 3

Light -> 200nm

Transmission electron -> 0.2nm

Question 4

How many metres in a kilometre, centimetres in a metre, millimetres in a centimetre, Micrometers in a millimetre and nanometers in a micrometer

Answer 4

1km = 1000m
1m = 100cm
1cm = 10mm
1mm = 1000 []m
1[]m = 1000nm

Question 5

What is the mitochondria

Answer 5

Where energy is transferred to during aerobic respiration

Question 6

What does a vacuole contain and what is its purpose

Answer 6

1. Cell sap

2. Keeps cell rigid

Question 7

Why aren’t onion cells green

Answer 7

They contain white chlorophyll

Question 8

Give organelles found inside a prokaryotic cell

Answer 8

.cytoplasm
.cell membrane
.cell wall
.single DNA loop

Question 9

Why do muscle cells contain many mitochondria

Answer 9

They have specialised to contain them because they require a lot of energy

Question 10

What is a nerve cell’s purpose + adaptations to carry it out

Answer 10

1. Carry electrical impulses around the body
   2.
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   - Dendrites to make connections with other nerve cells
   - Nerve endings to carry impulses to other cells

Question 11

What is a muscle cell’s purpose + adaptations to carry it out

Answer 11

1. To contract and relax to allow movement
   2.
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   - Special proteins that slide over each other
   - Many mitochondria to transfer energy needed for chemical reactions

Question 12

What is a sperm cell’s purpose + adaptations to carry it out

Answer 12

1. Carry genetic information from male parent
2. I
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   - Long tail to allow for fast swimming
   - An acrosome to store digestive enzymes to break down outer layers of egg

Question 13

What is a root hai cell’s purpose + adaptations to carry it out

Answer 13

1. Increase surface area of root to absorb water and minerals
   2.
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   -Large permanent vacuole to speed up water movement by osmosis
   -Greatly increase surface area available for water to move into cell

Question 14

What is a photosynthetic cell’s purpose + adaptations to carry it out

Answer 14

1. Allows plants to perform photosynthesis
   2.
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   - have many chloroplasts to trap light needed for photosynthesis
   - found in continuous layers in leaf + outer layers of stem

Question 15

What is a xylem cell’s 2 purposes + adaptations to carry it out (3)

Answer 15

1. -Transport water + mineral ions from roots to stems
   -Xylem tissue supports plant
   2.
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   -lignin builds up in spirals within cell wall
   -cells die and leave hollow tube to allow water and mineral ions through
   -spirals + rings of lignin also make tubes very strong/resistant

Question 16

What is a phloem’s purpose + adaptations to carry it out

Answer 16

1. Transports food made from photosynthesis to rest of plant
   2.
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   -cell walls between phloem cells breaks down to form sieve plates
   -phloem cells lose lots of structure but kept alive by companion cells