B1

Question 1

Name an advantage of a light microscope

Answer 1

cheap, can be used anywhere

Question 2

Name an advantage of an electron microscope

Answer 2

better resolution (0.2nm) , better magnification

Question 3

What’s the equation linking size of real object, magnification and size of image?

Answer 3

Size of real object = size of image / magnification

Question 4

Where do most reactions take place?

Answer 4

Cytoplasm

Question 5

What are ribosomes?

Answer 5

Where protein synthesis takes place, making all the proteins needed in the cell

Question 6

What does chlorophyll do?

Answer 6

Absorbs light for photosynthesis

Question 7

Describe a eukaryotic cell

Answer 7

cell membrane, cytoplasm, and genetic material enclosed in a nucleus

Question 8

describe a prokaryotic cell

Answer 8

cytoplasm and cell membrane surrounded by a cell wall. Genetic material forms a DNA loop rather than being in a nucleus, plasmids

Question 9

Name a adaption of a nerve cell

Answer 9

Long axon - carries impulses
Many dendrites- to make connections

Question 10

Name an adaption of a muscle cell

Answer 10

Special proteins - slide over each other to make fibres contract
Many mitochondria - for chemical reactions taking place

Question 11

Name an adaption of a root hair cell

Answer 11

Large surface area - so more water can move into the cell
Large vacuole - speeds up movement of water by osmosis
Many mitochondria - transfer energy needed

Question 12

Name an adaption of a photosynthetic cell

Answer 12

Many chloroplasts - more chlorophyll
Large permanent vacuole - keeps cell rigid for osmosis and keeps leaf spread out to capture lots of light

Question 13

Name an adaption of a xylem cell

Answer 13

Dead lignin spirals form a hollow tube that allows water to move
Dead cells keep cell strong and withstand pressure

Question 14

Name an adaption of a phloem cell

Answer 14

Sieve plates - allow water carrying dissolved food to move up and down
Companion cells keep them alive

Question 15

What is diffusion?

Answer 15

The spreading out of particles of any substance, resulting in a net movement from an area of high to low concentration, down the concentration gradient

Question 16

Define isotonic

Answer 16

Where the concentration of solutes in the solution outside and inside the cell are equal

Question 17

Define hypertonic

Answer 17

Where the concentration of solutes in the solution outside the cell is higher than inside, causing the cell to shrivel

Question 18

Define hypotonic

Answer 18

Where the concentration of solutes in the solution outside the cell is lower than inside, causing the cell to burst

Question 19

What is osmosis?

Answer 19

The movement of water from a dilute to concentrated solution through a partially permeable membrane

Question 20

Osmosis is important to keep plant cells ____

Answer 20

Turgid

Question 21

What is active transport?

Answer 21

Movement of molecules from a low to high concentration, against a concentration gradient. It requires energy

Question 22

What does active transport enable in PLANTS?

Answer 22

allows root hair cells to absorb mineral ions required for healthy growth

Question 23

What does active transport enable in ANIMALS?

Answer 23

Enables sugar molecules used for cell respiration to be absorbed into the gut into the blood where the concentration of sugar is higher

Question 24

Describe two adaptions of an effective exchange surface

Answer 24

• large surface area
• thin walls
  These both increase rate of diffusion as there is a shorter distance

Question 25

What is a plasmid in a prokaryotic cell?

Answer 25

closed-circles of DNA

Question 26

some prokaryotic cells contain small rings of DNA called…

Answer 26

plasmids

Question 27

What type of specialised plant tissue carries water and mineral ions up from the soil to the leaves?

Answer 27

Xylem

Question 28

How could you determine the concentration of glucose within a plant tissue?

Answer 28

Find the concentration of glucose solution in which the plant cell can be placed in where there’s no change in mass

Question 29

How could you determine the concentration of glucose within a plant tissue?

Answer 29

Find the concentration of glucose solution in which the plant cell can be placed in where there’s no change in mass