Breathing

Question 1

what happens to the diaphragm muscle when you exhale?

Answer 1

it relaxes, moves up and becomes dome shaped.

Question 2

what happens to the diaphragm muscle when you inhale?

Answer 2

it contracts, moves down and flattens

Question 3

what is ventilation?

Answer 3

the process of moving air in and out of the lungs.

Question 4

how do you test for carbon dioxide, using limewater?

Answer 4

1. breathe through a straw into limewater.

2. if it goes cloudy carbon dioxide is present

Question 5

how do you test for carbon dioxide, using bicarbonate indicator?

Answer 5

1. crush germinating peas and put them in a test tube - this causes the peas to release the CO2 in their cells.
2. then set up the experiment - 2 test tubes with a tube connecting them, on with the peas and one with the bicarbonate indicator.
3. if the bicarbonate indicator changes from red to yellow. CO2 is present.

Question 6

how do you measure heat energy produced by respiration?

Answer 6

put germinating peas in a conical flask and secure a thermometer in there with cotton wool - make sure no air can escape. Then read the thermometer at regular intervals.

Question 7

what is the percentage of carbon dioxide in inhaled air?

Answer 7

0.04%

Question 8

what is the percentage of carbon dioxide in exhaled air?

Answer 8

4%

Question 9

what is the percentage of oxygen in inhaled air?

Answer 9

21%

Question 10

what is the percentage of oxygen in exhaled air?

Answer 10

16%

Question 11

what is underneath the lungs?

Answer 11

a sheet of muscle called the diaphragm

Question 12

what are the lungs protected by?

Answer 12

the ribcage

Question 13

where are the lungs located?

Answer 13

inside the thorax (chest)

Question 14

what does breathing do?

Answer 14

1. gets air in and out of the lungs
2. gets oxygen from the air into the blood
3. gets carbon dioxide from the blood into the air

Question 15

what is the percentage of water vapour in inhaled air?

Answer 15

variable

Question 16

what is the percentage of water vapour in exhaled air?

Answer 16

always high

Question 17

what is the percentage of nitrogen in inhaled air?

Answer 17

78%

Question 18

what is the percentage of nitrogen in exhaled air?

Answer 18

78%

Question 19

how do ciliated cells keep lungs clean?

Answer 19

they have tiny cells that wave and move the mucus upwards and out of the lungs.

Question 20

how do goblet cells keep the lungs clean?

Answer 20

they make mucus which traps dust and bacteria

Question 21

what takes place in the alveoli?

Answer 21

gas exchange

Question 22

what things are in the structure of the thorax?

Answer 22

trachea
ribs 
intercostal muscle 
bronchiole
bronchus 
diaphragm 
pleural membrane
alveoli 
lungs 
pleural cavity

Question 23

what happens to the ribs when you inhale?

Answer 23

they move upwards and outwards.

Question 24

why are alveoli folded?

Answer 24

it gives a large surface area

Question 25

why are the walls of the alveoli only one cell thick?

Answer 25

there is a short distance so diffusion is fast

Question 26

why is the lining of the alveolus moist?

Answer 26

gases can dissolve which speeds up diffusion?

Question 27

what is each alveolus surrounded by and why?

Answer 27

blood capillaries to transport oxygen

Question 28

how many alveoli are there in each lung?

Answer 28

millions - there is a large surface area for gas exchange

Question 29

what happens to the intercostal muscles when you inhale?

Answer 29

they contract

Question 30

what happens to the pressure in the lungs when you inhale?

Answer 30

it decreases

Question 31

what happens to the intercostal muscles when you inhale?

Answer 31

they relax

Question 32

what is emphysema?

Answer 32

the alveoli gets a thicker wall which means diffusion takes longer - it also reduces surface area.

Question 33

what happens during gas exchange in the alveoli?

Answer 33

CO2 diffuses out and O2 diffuses in

Question 34

what does COPD do?

Answer 34

narrows the airways and destroys lung tissue

Question 35

what happens to the ribs when you exhale?

Answer 35

they move downwards and inwards

Question 36

what does smoking do to the alveoli?

Answer 36

damages the walls

Question 37

what happens to the pressure in the lungs when you exhale?

Answer 37

it increases

Question 38

what happens to the volume of the thorax when you exhale?

Answer 38

it decreases

Question 39

what happens to the volume of the thorax when you inhale?

Answer 39

it increases

Question 40

how is smoking cough caused?

Answer 40

harmful chemicals damage the cilia which leads to a build up of mucus which causes smoking cough