CELLS AND MOLECULES

Question 1

NUTRITION

Answer 1

• all need
• plants make ther eown
• animals feed on other organisms
• protiens for growth

Question 2

GROWTH+DEVELOPMENT

Answer 2

• growth-increasing in size

- developing- becoming more complex

Question 3

RESPIRATION

Answer 3

• release of energy from nutrients

- inside cells

Question 4

EXCRETION

Answer 4

• removal of waste chemicals made inside the body

- e.g breathing out CO2

Question 5

REPRODUCTION

Answer 5

-making new individuals of the same species

Question 6

MOVEMENT

Answer 6

-only living organisms can move their bodies or parts of of their bodies

Question 7

SENSITIVITY

Answer 7

-can sense change in their surroundings and react

Question 8

CONTROL INTERNAL CONDITIONS

Answer 8

-e.g animals can control their heart rate, body temperature and blood and glucose levels

Question 9

LEVELS OF ORGANISATION

Answer 9

ORGANELLE-parts of the cell
CELL
TISSUE- a group of simialr cells working together for 1 function
ORGANISM-a human being
ORGAN-mafde of tissue

Question 10

CELL MEMBRANE

Answer 10

allows what comes in or out of the cell

Question 11

CELL WALL

Answer 11

hold the structure of the cell like a skeleton

Question 12

CYTOPLASM

Answer 12

were chemical reactions take place

Question 13

NUCLEUS

Answer 13

hold the DNA+genes

controls what the cell does and when

Question 14

MITOCHONDRIA

Answer 14

releases energy from food

were aerobic respiration happenes

Question 15

CHLOROPLASTS

Answer 15

traps energy from sunlight
contains chlorophyll
this is then used for photosynthesis

Question 16

RIBASMES

Answer 16

very small

were protiens are made by joining amino acids

Question 17

3 WAYS SUBSTANCES INTO AND OUT OF CELLS

Answer 17

• diffusion
• osmosis
• active transport

Question 18

DIFFUSION

Answer 18

• movement of molecules or particles from a HIGH to LOW concentration
• e.g oxygen from the air in the alveoli into the blood

Question 19

OSMOSIS

Answer 19

the movement of water molecules across a semi-permable membrane.

• HIGH h2o concentration to a LOW h2o concentration
• to much water in red blood cell-swelling
• to little water in red blood cell-the plasma won’t absorb oxygen very well.

Question 20

ACTIVE TRANSPORT

Answer 20

this is the movement of molecules into a cell against a concentration gradient

• LOW TO HIGH concentration
• need energy from respiration
  e. g mineral ions from soil into root hair cells of plants

Question 21

TEST FOR STARCH

Answer 21

• add a few drops of iodine

- brown to black = starch is present

Question 22

TEST FOR PROTEIN

Answer 22

• add 1cm3 of Biuret reagent

- blue to purple=protein is present

Question 23

TEST FOR GLUCOSE

Answer 23

• add 1cm3 Benedicts reagent
• place in hot water bath (70°c-80°c) for 3-5 minutes
• blue to green=some glucose
• blue to red=lots of glucose

Question 24

TEST OF OSMOSIS

Answer 24

-pure water and potato slice
-water moves to potato cells
-potato mass would increase
>put potato in sugar solution
>water moves out of cell by osmosis

Question 25

TEST OF DIFFUSION

Answer 25

• agar blocks of jelly

- colour change from green to red