Week 5 Respiratory system

Question 1

What is the purpose of the respiratory system

Answer 1

Gas exchange (CO2/O2) between environment and body
Regulation of acid-base balance during exercise

Question 2

What is pulmonary respiration?

Answer 2

External ventilation, exchange of O2 and CO2 in the lungs

Question 3

What is cellular respiration?

Answer 3

Internal, utilization of O2 and CO2 production by the tissues.

Question 4

What is the definition of ventilation

Answer 4

Ventilation is mechanical process of moving air into (inspiration) and out of (expiration) the lungs

Question 5

What is the definition of diffusion

Answer 5

Movement of O2/CO2 molecules between the lungs and blood at the alveolus.

Question 6

What is the defence system in the respiration system

Answer 6

Warming of air - lungs are very sensitive and dont want cold air (done in conduction zone)
Mucus - traps particles
Cilia - spit or swallow
Macrophages - in alveoli, eat foreign bodies.

Question 7

What are the components of the conduction zone and what does it do

Answer 7

Trachea, bronchial tree and bronchioles

Conducts air to respiratory zone and warms and filters air

Question 8

What are the components of the respiratory zone and what does it do

Answer 8

Respiratory bronchioles and alveolar sacs

Exchanges of gases between air and blood

Question 9

What does the intrapulmonary pressure and diaphragm do in both inspiration and expiration

Answer 9

Inspiration - pressure lowered, diaphragm pushed downward, ribs lifted upward
Expiration - pressure increased, diaphragm relaxed and ribs pulled downward.

Question 10

What are the respiratory muscles involved in inspiration (4)

Answer 10

1. Sternocleidomastoid
2. scalenes
3. external/internal intercoastals
4. diaphragm

Question 11

What are the respiratory muscles involved in expiration (3)

Answer 11

1. Internal intercoastals
2. external/internal obliques
3. transverse/rectus abdominus

Question 12

Define tidal volume, alveolar ventilation and dead space ventilation

Answer 12

Tidal volume is the amount of air moved per breath
Alveolar ventilation is volume of air that reaches respiratory zone
Dead space ventilation is volume of air remaining in conducting airways

Question 13

What is Dalton’s Law

Answer 13

The total pressure of a gas mixture is equal to the sum of the pressure that each gas would exert independently

Question 14

What are the partial pressures of O2 and CO2 (PO2 and PCO2) in the:

1. Atmospheric air
2. Alveolar air
3. Pulmonary veins
4. Systemic arteries

Answer 14

1. PO2 = 159, PCO2 = 0.2
2. PO2 = 105, PCO2 = 40
   3 & 4. PO2 = 100, PCO2 = 40

Question 15

What are the partial pressures of O2 and CO2 (PO2 and PCO2) in the:

5. Tissues
6. Systemic veins
7. Pulmonary arteries

Answer 15

All 3 are
PO2 = 40
PCO2 = 46

Question 16

How is oxygen transported in the blood and what increases the amount of oxygen being able to be transported?

Answer 16

Haemoglobin transfers oxygen in the blood. Haemoglobin is in the RBCs. Haemoglobin can carry four oxygen molecules. High altitude training increases haemoglobin count. Myoglobin is what O2 binds to in haemoglobin.

Question 17

What is haemoglobin-oxygen saturation affected by

Answer 17

PO2, pH, temperature and PCO2 and PO2 binding.

Question 18

How is CO2 transported (3)

Answer 18

1. Dissolved in blood plasma (7-10%)
2. As bicarbonate ions resulting from dissociation of carbonic acid (60-70%)
3. Bound to amino groups on haemoglobin (carbonaminohemoglobin) 20-33%

Question 19

What happens to the artery-vein difference of O2 during rest and exercise

Answer 19

At rest 20mL of O2 per 100mL blood is taken from artery and 4-5mL O2 is taken by capillaries and 15-16mL O2 is taken by veins to go back to lungs
During exercise 15mL O2 is taken by capillaries to go to muscle while 5mL is taken by veins back to lungs

Question 20

What are the factors determining O2 uptake/delivery (3)

Answer 20

Oxygen content of blood
Amount of blood flow
Local conditions in muscle (pH, temp).

Question 21

Describe pons and medulla oblongata regarding regulation of pulmonary ventilation

Answer 21

They control the rate and depth of the breathing by sending impulses to respiratory muscles
Receive majority of input control signals from periphery

Question 22

List the regulators of pulmonary ventilation (8)

Answer 22

1. Central control - pons and medulla oblangata
2. Chemical changes (PCO2, PO2, H+)
3. Chemoreceptors
4. Muscle mechanoreceptors
5. Conscious control
6. Dyspnea/Hyperpnea
7. Hyperventilation
8. Valsava manouevere

Question 23

What is dyspnea and hypersnea

Answer 23

Dyspnea - Shortness of breathing

Hypersnea - Increase in breathing

Question 24

What is valsava manouevere

Answer 24

Breathing in and not allowing air to escape, during extensive period can reduce cardiac output

Question 25

What is ventilatory breakpoint

Answer 25

The point during intensive exercise at which ventilation increases disproportionally to the O2 consumption. When work rate exceeds 50-75% VO2 max, O2 delivery can no longer match intensity. This results in energy being derived from anaerobic glycolysis

Question 26

What is anaerobic threshold

Answer 26

Point during exercise of progressively increasing intensity at which metabolism becomes increasingly more anaerobic

Question 27

What are buffers in the blood (4)

Answer 27

Bicarbonate Haemoglobin Proteins Phosphates

Question 28

What are chemical buffers in the body

Answer 28

HCO3- Phosphate Proteins

Question 29

List the respiratory structure anatomy (9)

Answer 29

1. Nasal cavity 2. Nostril 3. Mouth 4. Larynx 5. Trachea 6. Right/left bronchus 7. Right/left lung 8. Pharanx 9. Diaphragm

Question 30

Name respiratory factors involved in acid-base balance (4)

Answer 30

1. important chemical H+ buffers in body 2. Pulmonary ventilation removes H+ from blood by the HCO3- reaction 3. Kidney - long term regulation, secrete Cl- and conserve Na+ and K+ 4. Acute - reuptake and oxidation of Lac- into contracting and non-contracting tissue

Question 31

Does ventilation limit performance?

Answer 31

Respiratory muscles are more resistant to fatigue than other muscles during heavy exercise (even though they take a lot of O2). Pulmonary ventilation isnt usually a limiting factor apart from in some elite athletes and people with asthma.