Respiratory System

Question 1

What is the function of the ribs

Answer 1

Protect internal organs of the thorax

Question 2

What is the function of the trachea

Answer 2

Brings air into the lungs. Supported by rings of cartilage that prevent it collapsing.

Question 3

What is the function of the bronchus

Answer 3

Branches off the trachea to bring air into the lungs, also supported by rings of cartilage

Question 4

What is the function of the pleural fluid

Answer 4

Fluid found in the pleural cavity (between the pleural membrane layers). It further reduced friction during breathing

Question 5

What is the function of the intercostal muscles

Answer 5

Muscles between the ribs that aid breathing

Question 6

What is the function of the pleural membranes

Answer 6

Thin layers that reduce friction between the lungs and the inside of the chest wall during breathing

Question 7

What is the function of the lungs

Answer 7

Organ where gas exchange occurs

Question 8

What is the function of the thorax

Answer 8

Part of the body between the neck and abdomen

Question 9

What is the function of the diaphragm

Answer 9

Sheet of muscle below the ribs that aids breathing

Question 10

What is the function of the nasal cavity

Answer 10

Air is warmed and filtered as it enters the body

Question 11

What is the function of the alveoli

Answer 11

Small air sacs that are the site of gas exchange

Question 12

What is the function of the bronchiole

Answer 12

Branch off the bronchi

Question 13

Describes the structure of the trachea

Answer 13

16-20 c shaped cartilage rings stacked on top of each other. It has 4 layers- the inner mucosal layer has a lining of ciliates tissue with goblet cells that produce mucus. The outer cartilage layer is sturdy but flexible and prevents the trachea collapsing

Question 14

What is the first defensive barrier to infection

Answer 14

Ciliated tissue in the trachea/ bronchi protects the lungs and airways provided by the action of mucus and cilia

Question 15

Describe the structure of the bronchi/ bronchioles

Answer 15

Lack cartilage in their walls, rely on smooth muscle to maintain wall integrity, club cells in the bronchioles form surfactant

Question 16

Describe the first type of pneumocytes

Answer 16

Thin cells that are adapted to carry out gas exchange, most type 1 are flat to minimise the distance that gases have to diffuse between the capillary and the alveoli

Question 17

Describe the second type of pneumocytes

Answer 17

Secrete a solution called surfactant that creates a moist surface inside the alveoli to prevent the side of the alveolus adhering to each other. This thin layer creates a film of moisture that supports diffusion of gases

Question 18

What 5 specialisations are there of the alveoli for gas exchange

Answer 18

-large surface area to volume ratio
-good blood supply
-short diffusion difference
-moisture levels
-body temperature

Question 19

What mechanics are involved during inhalation

Answer 19

-diaphragm contracts (moves down) low pressure draws air inwards
-external intercostal contract (rib cage up and outwards)

Question 20

What mechanics are involved in exhalation

Answer 20

-elastic recoil of the tissue of the lungs
-diaphragm relaxes and moves up (increases pressure so forcing air out of the lungs)
-External intercostals relax

Question 21

What 4 factors increase diffusion

Answer 21

-short distance
-strong gradient
-temperature
-surface area of type 1 pneumocytes is high

Question 22

What are the three methods that carbon dioxide molecules are transported in the blood from body tissues to the lungs

Answer 22

Dissolution directly into the blood 5-7%
Binding to haemoglobin 10%
Carried as a bicarbonate ion 83-85%

Question 23

What does pulmonary surfactant do

Answer 23

Form a layer on the surface of the moisture lining with hydrophilic heads facing the water and hydrophobic tails facing the air. This reduces surface tension and stops the lungs from collapsing