Respiratory 1- Respiratory Physiology Lecture

Question 1

What are the functions of the respiratory system?

Answer 1

Gas exchange – Oxygen added to the blood from the air, carbon dioxide removed from the blood into the air.

Acid base balance – regulation of body pH (see renal lectures)

Protection from infection

Communication via speech

Question 2

Why do we breathe?

Answer 2

to produce energy - burn oxygen and carbohydrate and produce carbon dioxide as a waste product

Question 3

What is the respiratory system responsible for?

Answer 3

oxygen in and carbon dioxide out

Question 4

What does the CVS do? (cardiovascular system)

Answer 4

to deliver fuel to the active cells within the tissues, and remove waste products.

Question 5

What links the respiratory and CV systems?

Answer 5

gas exchange

Question 6

What is cellular/ internal respiration?

Answer 6

biochemical process that releases energy from glucose either via Glycolysis or Oxidative Phosphorylation

Question 7

What is external respiration?

Answer 7

movement of gases between the air and the body’s cells, via both the respiratory and cardiovascular systems.

Question 8

Describe the difference between pulmonary and systemic circulations?

Answer 8

Pulmonary: It delivers CO2 (to the lungs) and collects O2 (from the lungs)
Pulmonary artery- rich in CO2

Systemic: Collects CO2 and delivers O2 to peripheral tissues
Systemic vein- rich in CO2

Question 9

What is the function of pulmonary vein?

Answer 9

carries oxygenated blood

Question 10

What is function of pulmonary artery?

Answer 10

carries deoxygenated blood

Question 11

Function of pulmonary circulation?

Answer 11

specialised part of CVS

just serves lungs

opposite to systemic

Question 12

Blood flow in pulmonary circulation?

Answer 12

takes blood from right side of body to lungs and to left side of body

Question 13

Blood flow in systemic circulation?

Answer 13

taking oygenated blood from heart and taking to peripheral

Question 14

What is the net volume of gas exchanged in the lungs per unit time?

Answer 14

250ml/min O2; 200ml/min CO2
and equal to the net vol exchanged in tissues

Question 15

What is normal respiration rate and and max?

Answer 15

12-18 breaths/min at rest,
Can reach 40 - 45 at max. exercising capacity in adults

Question 16

Describe nose and functions?

Answer 16

cilia and mucus trap particles and warm and moisten the air

Question 17

Describe pharynx and functions?

Answer 17

from your nose, air moves down into pharynx or throat- shared with digestive system

Question 18

Describe epiglottis and functions?

Answer 18

small flap of tissue folds over the trachea and prevents food from entering it when you swallow

Question 19

Describe larynx?

Answer 19

contains your vocal chords- vibrate to produce sound

Question 20

Describe trachea and functions?

Answer 20

from the pharynx air moves down towards the lungs through your trachea.
Made up of stiff rings of cartilage that support and protect it.

Question 21

Describe bronchus and functions?

Answer 21

air moves from the trachea into the right and left bronchi - which lead inside the lungs.

Question 22

What are the parts of upper and lower respiratory tract?

Answer 22

upper- mouth, nasal cavity, pharynx , larynx

lower- trachea, bronchi , lungs

Question 23

What is the lower respiratory system enclosed by?

Answer 23

thorax, bounded by ribs, spine and diaphragm

Question 24

How can airway diameter and therefore resistance to air flow, be altered ?

Answer 24

by activity of bronchial smooth muscle to protect alveoli from inhaling dangerous substances

Question 25

describe how the bronchi are divided further and further on either side of the lungs?

Answer 25

Primary Bronchi (Main Bronchi):
The trachea bifurcates into the right bronchus and left bronchus, each entering the corresponding lung.
The right bronchus is wider, shorter, and more vertical compared to the left bronchus.

Secondary Bronchi (Lobar Bronchi):
Each primary bronchus divides into secondary bronchi.
The right lung has three secondary bronchi (one for each lobe: upper, middle, and lower).
The left lung has two secondary bronchi (one for the upper lobe and one for the lower lobe).
These bronchi branch off to serve the individual lobes of the lungs.

3. 3. Tertiary Bronchi (Segmental Bronchi):
      Each secondary bronchus divides further into tertiary bronchi.
      These bronchi serve the bronchopulmonary segments, which are distinct sections of the lung that can function independently.
      The right lung has 10 bronchopulmonary segments, while the left lung has 8 or 9, depending on anatomical variations.
      Tertiary bronchi can be recognized by their branching patterns to each segment.

Smaller Bronchi:
As the bronchi continue to branch, they become progressively smaller in diameter.
The walls of these smaller bronchi become thinner, and cartilage plates (supporting tissue) start to diminish.

Bronchioles:
Eventually, the bronchi become bronchioles.
Bronchioles have no cartilage and are smaller than 1 millimeter in diameter.
These are the smallest airways that still have smooth muscle in their walls, allowing for constriction and dilation.

Alveolar Ducts and Alveoli:
Respiratory bronchioles further divide into alveolar ducts, leading to the alveolar sacs, which contain alveoli.
The alveoli are tiny air sacs where oxygen and carbon dioxide are exchanged between the lungs and the bloodstream.

Question 26

What muscle separates thoracic from abdominal?

Answer 26

diaphragm - changes vol of thoracic cavity

Question 27

What is anatomical dead space?

Answer 27

The conducting zone of the airways consists of the trachea, bronchi (highest points of resistance to air flow), and bronchioles. Air in these airways is referred to as Anatomical Dead Space as it does not participate in gas exchange as the walls of the airways are too thick.

Question 28

What is the respiratory zone?

Answer 28

The respiratory zone of the airways consists of the alveoli, which are the sites of gas exchange, and those airways to which alveoli are attached.

Question 30

What is a cluster of alveolis surrounded by?

Answer 30

elastic fibres (help push air out of alveolis)
and a network of capillaries

Question 31

What are alveoli composed of?

Answer 31

composed of type I cells for gas exchange and type II cells that synthesize surfactant.

Question 32

What do alveolar macrophages do?

Answer 32

ingest foreign material that reaches the alveoli