SB8

Question 1

give an example of a chemical reaction

Answer 1

respiration

Question 2

give an example of a mechanical action

Answer 2

breathing

Question 3

respiration equation

Answer 3

glucose + oxygen –> carbon dioxide + water

Question 4

describe and explain the sa: vol ratio of multicellular organisms

Answer 4

small sa: vol ratio because molecules needed can’t diffuse fast enough

Question 5

what system do multicellular organisms need

Answer 5

transport system to move substances in the body

Question 6

describe + link the sa: vol ratio of multicellular organisms

Answer 6

large sa: vol ratio for slower diffusion

Question 7

how are lungs adapted

Answer 7

have lots of alveoli

Question 8

how are alveoli adapted

Answer 8

large sa for faster diffusion and one cell thick for good blood supply

Question 9

when does diffusion occur in the lungs and what gases are involved

Answer 9

gas exchange of oxygen and carbon dioxide

Question 10

what are alveoli surrounded by

Answer 10

capillaries

Question 11

do larger objects have a large or small sa: vol rato

Answer 11

small

Question 12

what four things does blood contain

Answer 12

plasma, RBC, WBC, platelets

Question 13

what is plasma + what does it do

Answer 13

the liquid part of blood that transports food molecules around the body

Question 14

what do RBCs do + what else are they known as

Answer 14

transport O2 and absorb CO2 - also known as erythrocytes

Question 15

how are RBCs adapted

Answer 15

prokaryotic for more space + a concave shape for large sa

Question 16

what do WBCs do + what two types of WBCs are there

Answer 16

fight infection - two types are phagocytes and lymphocytes

Question 17

what are phagocytes and what do they do

Answer 17

type of WBC - kill microorganisms by phagocytosis which involves engulfing, killing and digesting it

Question 18

what are lymphocytes and what do they do

Answer 18

type of WBC - release antibodies

Question 19

what do platelets do + what are they covered in

Answer 19

stick to damaged blood vessels forming clots over the wound which stops bleeding - they are covered in proteins

Question 20

what do arteries do + how are they adapted

Answer 20

carry blood away from the heart - adapted with thick elastic cell walls to cope with the pressure of blood (which is high as it is thick)

Question 21

what do capillaries do + how are they adapted

Answer 21

carry blood close to cells - adapted with thin cell walls to allow O2 and nutrient diffusion

Question 22

anaerobic respiration equation + what kind of reaction is it

Answer 22

glucose –> lactic acid
- an exothermic reaction