cell transport

Question 1

how do you calculate percentage change in mass after osmosis?

Answer 1

change in mass/start mass x 100

Question 2

solute+solvent=?? [1]

Answer 2

solution

Question 3

osmosis [2]

Answer 3

movement of water molecules from a dilute to concentrated solution

Question 4

what can osmosis only happen through? [1]

Answer 4

a partially permeated membrane

Question 5

how is the small intestine adapted for absorsion of nutrition? [4]

Answer 5

• many villi and many microvilli- increases the surface area
• thin walls of the villus- short diffusion distance
  -good blood supply- maintains the concentration gradient
  -many mitochondria- for respiration to release energy for active transport.

Question 6

how are root cells adapted for absorpsion of sustances from the soil? [3]

Answer 6

projection (bit that juts out) makes a larger surface area which means better absorbtion

Question 7

hypotonic solution [1]

Answer 7

one which is more dilute than the cell

Question 8

isotonic solution [1]

Answer 8

one which is the same concentration as the cell

Question 9

hypertonic solution [1]

Answer 9

one which is more concentrated than the cell

Question 10

what will happen to cells if put in a hypotonic solution? [2]

Answer 10

animal cell bursts, plant cell turgid (firm)

Question 11

what will happen to cells if put in an isotonic solution? [2]

Answer 11

animal cell normal, plant cell flacid (limp)

Question 12

what will happen to cells if put in a hypertonic solution? [2]

Answer 12

animal cell shrivels, plant cell plasmolysed (shrunk)

Question 13

What name is given to the process by which water moves across a membrane? [1]

Answer 13

osmosis

Question 14

suggest three factors that can affect the rate of diffusion

Answer 14

-concentration gradient
-surface area
-wall thickness

Question 15

active transport needs _____ to take place

Answer 15

energy

Question 16

describe the difference between magnification and resolution.

Answer 16

magnification- the increase in size of an object when viewed through a microscope,
resolution-the ability of a microscope to distinguish between two separate objects that are close together.

Question 17

describe the advantages and disadvantages of using a light and electron microscope.

Answer 17

light- cheaper and small but low magnification and resolution
electron- big and expensive high magnification and resolution

Question 18

cell membrane function

Answer 18

controls what goes in and out of the cell

Question 19

Nucleus function

Answer 19

Contains the cell’s genetic material (DNA) which controls the cells activity

Question 20

Mitochondria function

Answer 20

powerhouse of the cell, where aerobic respiration occurs, releasing energy

Question 21

Cytoplasm function

Answer 21

where chemical reactions happen, contains enzymes

Question 22

Ribosome function

Answer 22

makes proteins

Question 23

Vacuole function

Answer 23

stores food, nutrients and waste products

Question 24

cell wall function

Answer 24

provides strength and structure, protects the the cell

Question 25

Chloroplast function

Answer 25

Where photosynthesis takes place

Question 26

what are the differences between animal and plant cells

Answer 26

-Plant cells have cell walls, animal cells only have a cell membrane -Plant cells contain chloroplast, animals cells don’t -Plant cells have vacuoles, animals cells don’t -Plant cells have a rectangular shape while animal cells have a circular shape

Question 27

Why do animals have specialised cells?

Answer 27

to carry out specific functions

Question 28

compare the structure of a specialised and generalised animal cell.

Answer 28

generalised cells have a more simple structure whereas specialised cells have a more complex structure

Question 29

how is a sperm adapted to its function

Answer 29

-Have a long tail so they can swim to find an egg -Contain many mitochondria to release energy for movement -Enzymes in the head of the sperm help it break into into the egg -Nucleus contains half the DNA code required to make a person

Question 30

how is a nerve cell adapted to its function

Answer 30

-extremely elongated -many branches at both ends to connect to other nerve cells

Question 31

why does surface area affect the rate of diffusion.

Answer 31

As the surface area of the membrane increases, the rate of diffusion also increases because there is more space for molecules to diffuse

Question 32

active transport

Answer 32

the movement of substances against their concentration gradient (low to high)