Respiratory - The lung 2/2

Question 1

How do the epithelial cells change as the cells get deeper into the reparatory tract?

Answer 1

They become shorter (i.e. go from columnar to cuboidal to squamous in the alveoli)

Question 2

What is the purpose of the smooth muscle surrounding the bronchiole?

Answer 2

Can constrict or relax to control flow of air

Question 3

What does the control of smooth muscle in the bronchiole make it?

Answer 3

The main controller of air flow

Question 4

What happens in an asthma attack related to the bronchioles?

Answer 4

Asthma is when the smooth muscle in the bronchioles constrict

Question 5

How can an asthma attack be alleviated?

Answer 5

With a bronchodilator (relaxes the smooth muscle)

Question 6

What is a common bronchodilator?

Answer 6

Salbutamol

Question 7

Label the diagram

Answer 7

Question 8

What are alveolar sacs?

Answer 8

A group of alveoli

Question 9

In the terminal bronchiole, is there gas exchange? Why?

Answer 9

No because the wall of the bronchiole is too thick to allow the diffusion of gases (i.e. gas exchange)

Question 10

What are alveoli?

Answer 10

A group of alveolus

Question 11

What are alveolus?

Answer 11

An individual air sac in the lung

Question 12

Label the diagram

Answer 12

Question 13

What is the function of the surfactant cells?

Answer 13

It secretes a surfactant that decreases the surface tension inside the alveolus

Question 14

What is the advantage of secreting a surfactant inside the alveolus?

Answer 14

It prevents it from collapsing therefore reducing the work of breathing as it means the alveolus doesn’t have to re-inflate the cells every time you breathe

Question 15

What is the function of the alveolar macrophage?

Answer 15

It is a last line of immune defence against any foreign bodies that get into the lungs

Question 16

What is the location of the alveolar macrophage?

Answer 16

They move around so don’t have a specific position

Question 17

Label the diagram

Answer 17

Question 18

What is the diffusion barrier trying to do?

Answer 18

Trying to minimise its distance between the blood and air

Question 19

How close are the basement membranes of the alveoli and capillaries? Why?

Answer 19

They are touching to minimise the distance between air and blood

Question 20

What is the trend of the epithelial lining in the lungs?

Answer 20

Starts off columnar (i.e. thick) and trends into the lower respiratory tract getting thinner into squamous cells

Question 21

What is the trend of the smooth muscle in the lungs?

Answer 21

Less smooth muscle in the upper tract with the most in the bronchiole but NONE in the alveoli

Question 22

What does the trend of smooth muscle indicate about the control of air flow?

Answer 22

The lower respiratory tract has greater control over air flow than the upper respiratory tract

Question 23

What is the trend of the mucous glands in the lungs? Why?

Answer 23

Found only in the upper respiratory tract (trachea and bronchus) where there is more space for the glands in the thicker layers

Question 24

What is the trend of the cartilage in the lungs?

Answer 24

Found only in the upper respiratory tract (trachea and bronchus)

Question 25

What are the subdivision of the lungs?

Answer 25

Primary, secondary and tertiary bronchi

Question 26

What are the primary bronchi?

Answer 26

The left and main stem supplying each lung

Question 27

What are the secondary bronchi?

Answer 27

The bronchi supplying each of the lobes of the lungs (2 on the left, 3 on the right)

Question 28

Wha are the tertiary bronchi?

Answer 28

The segmental bronchi supplying segments of the lung (8 on the left 10 on the right)

Question 29

What does each segment of the lung have? What does it make this?

Answer 29

Each segment has its own air and blood supply making it a seperate functional unit

Question 30

How does the segment aid a patient with lung disease?

Answer 30

If there is the disease isolated to a single segment it can be removed without affect the rest of the lung adversely

Question 31

What membrane covers the lungs?

Answer 31

The pleurae

Question 32

What is the structure of the pleurae?

Answer 32

A double layered membrane that is continuous at the root of the lung (hilum) with a thin film of fluid separation the layers

Question 33

Label the diagram

Answer 33

Question 34

What is the purpose of the pleural fluid?

Answer 34

Allows sliding between the pleurae layers and also prevents them from separating (liquid layer creates suction between layers FYI)

Question 35

What are the muscles on the rib cage that are used for breathing called?

Answer 35

Internal and external intercostal muscles

Question 36

What are the external intercostal muscles used for?

Answer 36

They help to move the ribs up which result in the expansion of the lungs causing ~25% of the air movement of the lungs

Question 37

What are the internal intercostal muscles used for?

Answer 37

They are used during exercise to increase the rate of expiration by pulling the rib cages down forcing air out of the lungs faster

Question 38

What is quiet breathing?

Answer 38

Breathing when you are not exerting yourself

Question 39

Why you are doing quiet breathing, what is the energy usage?

Answer 39

Inspiration is active (external intercostal muscles and diaphragm contract), expiration is passive (both relax)

Question 40

When you are breathing during exercise, what is the energy usage?

Answer 40

Inspiration is active (external intercostal muscles and diaphragm contract), and expiration is active (internal intercostal muscles contract)

Question 41

How does the diaphragm control air flow into the lungs?

Answer 41

The diaphragm is connected onto bones via the vertebrae and the sternum and is connected to the floor of the thorax (i.e. bottom of the lungs) by the pleurae fluid. When it contracts it pulls the lungs downwards lowering air pressure therefore brining air into the lungs, when it relaxes it makes the lungs smaller therefore pressure increases expelling air

Question 42

Label the diagram

Answer 42

Question 43

What part of the diaphragm contracts?

Answer 43

The muscular portion

Question 44

What kind of muscle is the muscular portion? What is it innervated by?

Answer 44

Fast action skeletal muscle Phrenic nerve

Question 45

What portion of the bulk flow of air during quiet breathing is caused by the diaphragm?

Answer 45

75%