26. Breathing

Question 1

Label diagram

top to bottom

Answer 1

nose and mouth
larynx
epiglottis
trachea
rings of cartilage
bronchus
bronchiole
alveoli
lungs
ribs
diaghram
pleural membrane and pleural cavity

Question 2

Function of nostrils

Answer 2

Filters the air:
Sticky mucus traps dirt and germs
Hairs/cilia trap dirt and germs
warms and moistens air-easier diffusion of oxygen

Question 3

Function of:
Larynx
Epiglottis
Intercostal muscles
Rings of cartilage

Answer 3

Larynx: Produces noise
Epiglottis: Stops air moving down the oesophagus
Intercostal muscles: Contract to move ribcage up and down
Rings of cartilage: Protect trachea

Question 4

Function of diaghram

Answer 4

a sheet of muscle that moves up and down during breathing

Question 5

Function of:

1. Trachea
2. Bronchus
3. Bronchiole

Answer 5

1. Trachea: brings air in and out of lungs, has cilia and mucus to filter air
2. Brings air from trachea to lungs
3. Brings air from bronchus to alveoli

Question 6

Function of alveoli

Answer 6

Little sacs at end of bronchiole where gaseous exchange occurs.

Question 7

Function of pleural membrane and cavity

Answer 7

Membrane: Surrounds the lungs
Cavity: reduces friction during breathing

Question 8

Process of inhalation

Answer 8

1. Intercostal muscles contract
2. Causes ribs to pull up and out
3. Diaphragm flattens downwards
4. This causes volume of thorax cavity to increase. So air pressure in chest cavity drops. More air is drawn into the lungs and alveoli

Question 9

Process of Exhalation

Answer 9

1. Intercostal muscles relax
2. Ribs pull down and in
3. Diaphragm pushes upwards
4. Causes volume of thorax cavity to decrease. Air pressure in chest cavity rises. Air breathed out

Question 10

Gaseous exchange

Answer 10

1. Oxygen diffuses through the alveolus and capillary linings
2. Passes into the RBCs
3. O2 diffuses into body cells
4. CO2 diffuses from body cell into plasma
5. CO2 is diffused into alveoli and is exhaled.

Question 11

How is oxygen transported

Answer 11

Haemoglobin in RBC

Question 12

How is CO2 transported

Answer 12

Dissolved in plasma of the blood

Question 13

By what method are gases exchanged

Answer 13

Diffusion

Question 14

Adaptations of the lungs and alveoli for gas exchange

Answer 14

Alveoli have large surface area (numerous alveoli)
Large supply of capillaries around alveoli (less distance for O2 to travel)
Alveoli walls 1 cell thick
Alveoli walls are elastic and moist.

Question 15

What kind of action is breathing?

Answer 15

Automatic: involuntary reflex action

Question 16

What is the controlling factor of breathing and what part of the body detects this factor

Answer 16

Carbon dioxide
Medulla Oblongata (has receptors to detect CO2 concentration)

Question 17

What happens when CO2 levels increase?

Answer 17

1. CO2 levels increase because of increased respiration (exercise)
2. CO2 dissolves in the blood
3. pH of blood falls (acidic)
4. Medulla oblongata detects this change
5. It sends an impulse to the intercostal muscles and diaphragm to contract.
6. Breathing rate increases to exhale the increased CO2

Question 18

Name 3 breathing disorders

Answer 18

Asthma
Bronchitis
Pneumonia
TB
Emphysema

Question 19

Asthma symptoms

Answer 19

Wheezing, 
short of breath, 
tightness of chest, 
unable to take in much oxygen,
coughing

Question 20

Asthma causes

Answer 20

Pollen, Dust, Damp air, Certain animals, Chemicals, Smoke, Exercise

Question 21

Asthma treatment and prevention

Answer 21

Specific drug treatments
Steroids
Inhaler
Bronchodilators
Nebulizer
Prevention: Identify triggers and avoid or remove