Topic 7 The Respiratory System

Question 1

How many breaths does the average person take when at rest?

Answer 1

12-18 per minute

Question 2

What are the components of the respiratory system?

Answer 2

• The airway
• The lungs
• The muscles of respiration

Question 3

What is the purpose of the cilia in the nasal cavities?

Answer 3

To warm the air and trap any potentially harmful particles

Question 4

What are ‘cardiac impressions’?

Answer 4

The special grooves on each lung in which the heart sits

Question 5

What do terminal bronchioles further divide into?

Answer 5

• Respiratory bronchioles
• Alveolar ducts
• Alveolar sacs

Question 6

What shape is the base of each lung?

Answer 6

Concave

Question 7

What is the term for the exchange between the body and the environment of CO2 and O2?

Answer 7

External respiration

Question 8

What is the conduction zone?

Answer 8

The name given to the collective of the nasal passages, pharynx, larynx, bronchi and bronchioles

Question 9

What are the components of the conduction zone?

Answer 9

• Nasal passages
• Pharynx
• Larynx
• Bronchi
• Bronchioles

Question 10

Roughly how big, in an adult human, is the respiratory surface?

Answer 10

About 140m squared

Question 11

What are the components of the respiratory zone?

Answer 11

• Bronchioles
• Alveolar ducts
• Alveoli

Question 12

What is the respiratory zone?

Answer 12

Where gas exchange occurs during respiration

Question 13

What is haemoglobin?

Answer 13

An iron-containing protein

Question 14

How does haeomoglobin function?

Answer 14

It binds with oxygen in the lungs in order to transport it to tissues

Question 15

What is ‘partial pressure’?

Answer 15

The amount of each individual gas in the atmosphere

Question 16

What is haemoglobin?

Answer 16

An iron-containing protein present in red blood cells

Question 17

What does haemoglobin do?

Answer 17

Binds to oxygen in the lungs and transports it to tissues

Question 18

What is haemoglobin formed of?

Answer 18

Four polypeptide chains; two alpha & two beta chains

Question 19

What is a haem group?

Answer 19

What gives haemoglobin its ability to bind to oxygen

Question 20

What are haem groups comprised of?

Answer 20

An iron atom which is able to bind with an oxygen molecule

Question 21

What is the force which governs binding of O2 to Hb?

Answer 21

Positive cooperativity

Question 22

What is deoxyhaemoglobin?

Answer 22

Hb which does not have O2 bound to it

Question 23

What biological factors affect Hb binding?

Answer 23

• CO2
• Acidity
• 2,3-DPG (2,3-diphosphoglyceric acid)
• Exercise
• Temperature

Question 24

What is the Bohr effect?

Answer 24

The name for the influence which CO2 and acidity have on the affinity of haemoglobin for oxygen

Question 25

A reaction between which molecules generates bicarbonate?

Answer 25

Water and carbon dioxide

Question 26

What is the formula of bicarbonate?

Answer 26

HCO3

Question 27

What is the equation for the reaction which produces bicarbonate?

Answer 27

H2O + CO2 H2CO3 H+ + HCO3

Question 28

What does carbon dioxide combine with water to form?

Answer 28

Carbonic acid

Question 29

Which enzyme is facilitates and speeds up the reaction that produces carbonic acid?

Answer 29

Carbonic anhydrase

Question 30

What causes sickle cell disease?

Answer 30

A nucleotide substitution (a glutamic acid codon is converted to a valine codon)

Question 31

What is the cause of the cell distortion in HbS (sickle cell disease)?

Answer 31

Valine amino acids binding to each other when the HbS becomes deoxygenated

Question 32

Is sickle cell a recessive or dominant condition?

Answer 32

Recessive; two mutated alleles are required for the condition to develop

Question 33

What is haemolysis?

Answer 33

The rupture and destruction of erythrocytes

Question 34

What are thalassaemias?

Answer 34

A group of inherited autosomal recessive disorders

Question 35

What do thalassaemias cause?

Answer 35

Anaemia

Question 36

Alterations in *what?* is the principle driver of respiration in humans?

Answer 36

PCO2

Question 37

Neurons from which regions of the brain synapse on to the diaphragm and intercostal muscles to regulate breathing rate?

Answer 37

Pontine and medullary

Question 38

What are neuromuscular junctions?

Answer 38

They synapse chemical junction between a motor neuron and a muscle fibre

Question 39

What are type 1 glomus cells?

Answer 39

Peripheral chemoreceptors which sense and respond to the oxygen, carbon dioxide and pH levels of the blood

Question 40

What chemical do glomus cells release across the neuromuscular junction?

Answer 40

Dopamine

Question 41

What is the effect of the dopamine that glomus cells release on nerves?

Answer 41

It causes afferent signals to be sent to the medullary respiratory centres, which in turn send action potentials to the phrenic and intercostal nerves

Question 42

What is the overall effect or purpose of the dopamine released by glomus cells?

Answer 42

To increase the respiration rate

Question 43

Which parts of the brain are involved with the control of breathing during speech and behavioural tasks which modify breathing?

Answer 43

* Motor cortex * Thalamus * Cerebellum

Question 44

What is hypopnoea?

Answer 44

Reduction in airflow

Question 45

In respiration, where does gas exchange occur?

Answer 45

In the respiration zone - the bronchioles, alveolar ducts and alveoli

Question 46

How is most of the CO2 carried in the blood?

Answer 46

As bicarbonate

Question 47

How is O2 carried in the blood?

Answer 47

Bound to haemoglobin which is present in erythrocytes

Question 48

What is the Bohr effect?

Answer 48

The influence of CO2 and acidity on the affinity of haemoglobin for oxygen

Question 49

What is the Haldane effect?

Answer 49

The influence of oxygen on haemoglobin transport of carbon dioxide