Respiratory System

Question 1

What is external respiration?

Answer 1

exchange of gases between blood and lungs

Question 2

What is internal respiration?

Answer 2

exchange of gases between cells and blood

Question 3

What is in the upper respiratory tract?

Answer 3

nose, pharynx, larynx

Question 4

What is in the lower respiratory tract?

Answer 4

Trachea and lungs

Question 5

What is the conductive zone?

Answer 5

it includes all airways

Question 6

What is the respiratory zone?

Answer 6

alveoli, where gas exchange occurs

Question 7

What is the structure of the nasal cavity?

Answer 7

Includes 2 equal passages, the lining is ciliated columnar epithelium. Paranasal sinuses are cavities in the face and cranium bones.

Question 8

What is the function of the nasal cavity?

Answer 8

Passageway for air
Warming
Filtering and cleaning (hair and mucus)
Humidification (air travelling through moist mucus)
Smell

Question 9

What is the structure of the pharynx?

Answer 9

Nasopharynx, oropharynx and laryngopharynx

Question 10

What is the function of the pharynx?

Answer 10

Passageway for air and food
Warming
Humidifying
Hearing (connection to the middle ear)
Protection (lymphatic tissue; tonsils)
Speech: acting as a resonating chamber for sound ascending from larynx
Facilitating swallowing via palate and uvula

Question 11

What happens to the uvula and soft palate when swallowing?

Answer 11

they are pushed upwards close to the nose

Question 12

What is the larynx?

Answer 12

Composed of several cartilages including thyroid and cricoid cartilage. Includes 2 pale folds of vocal cords stretched across laryngeal opening. Epiglottis: a leaf shaped fibroelastic cartilage attached on a flexible stalk. The lid of the voice box and will close the box during swallowing.

Question 13

What is the function of the larynx?

Answer 13

sound (pitch, volume, tone)
Speech
Protection of lower respiratory tract when swallowing
Passageway for air
Warming
Humidifying
Filtering

Question 14

What is the trachea?

Answer 14

10-11cm long
Composed of 16-18 C-shaped cartilages: incomplete at posterior to allow expansion of oesophagus during swallowing
Position:  
Lateral: lungs, 
Posterior: oesophagus 
Anterior: aorta, sternum
Inferior: RT and LT Bronchi

Question 15

What is the function of Trachea?

Answer 15

Air of passageway
Warming, humidifying and filtering
Mucociliary escalator: regular beating of the cilia membrane upwards towards larynx where it is swallowed or coughed u
Cough reflex

Question 16

What is the structure of the lungs?

Answer 16

Composed of the bronchi and smaller air passages, alveoli, connective tissue, blood and lymph vessels and nerves embedded in an elastic connective tissue. Contains 300 million alveoli in each lung. Includes 5 lobes.

Question 17

What is the name for the cells lining the alveoli?

Answer 17

Pneumocytes

Question 18

what are the two types of cells in the alveoli?

Answer 18

PneumocyteType 1

PneumocyteType 2

Question 19

What is the function of PneumocyteType 1?

Answer 19

oxygen in — carbon dioxide out

Question 20

what is the function of PneumocyteType 2?

Answer 20

Surfactant

Question 21

What is the function of the lungs?

Answer 21

External respiration via diffusion

Question 22

What is a Pleura?

Answer 22

A closed sac of serous membrane for each lung. It includes the visceral pleural. the parietal pleural. A cavity inside the sac: pleural cavity a few millilitre of plural fluid allowing the two layers to glide over each other

Question 23

What are the breathing muscles?

Answer 23

Intercostal muscles

Diaphragm

Question 24

Describe the Intercostal muscles.

Answer 24

11 pairs between 12 pairs of ribs. Arranged in 2 layers: internal and external. The first pair of ribs are fixed, when these muscles contract rib cage would move upwards allowing lungs to expand.

Question 25

Describe the diaphragm.

Answer 25

It is a dome- shaped muscular structure. Separating thoracic and abdominal cavities. During respiration it contracts and moves towards abdomen allowing lungs to expand.

Question 26

Describe the transport of gases in blood stream.

Answer 26

Oxygen is combined with Haemoglobin (98.5%). Solution is plasma water (1.5%).

Carbon dioxide appears as HCO3 in the plasma (70%). Combined with Haemoglobin (23%). Dissolved in plasma (7%)

Question 27

What is the pH of blood?

Answer 27

between 7.35 and 7.45

Question 28

How is respiration controlled?

Answer 28

The nervous system is the respiratory centre. Chemoreceptors are located both centrally in the the medulla of the brain and peripherally in the arch of the aorta and carotid bodies.

Question 29

What are chemoreceptors?

Answer 29

They are sensitive to the increase of arterial PCO2.

Sensitive to small reduction of PO2. Substantial PO2 depresses breathing.

Question 30

what are the changes in pregnancy?

Answer 30

Chest shape alters during pregnancy
The ribs flare out, prior to mechanical pressure exerted by the growing uterus. the diaphragm rises by approx 4cm. the diameter of the chest )anterior- posterior and transverse diameters) both increase by 2 cm, leading to overall increased chest circumference of 5-7 sm. These effects are due to progesterone and relaxing on the the ribcage and associated ligaments.

Question 31

what happens to blood during pregnancy?

Answer 31

Expanded blood volume and vasodilation can produce oedema (swelling) and hyperaemia (Increase blood flow) in the upper respiratory tract. Pregnant women can often experience nasal congestion, epistaxis (nosebleeds) and sometimes even changes in voice

Question 32

What effect does progesterone have during pregnancy?

Answer 32

Progesterone is a respiratory stimulant; it increases the sensitivity of the peripheral and central chemoreceptors for carbon dioxide. Therefore respiratory drive is stimulated at lower carbon dioxide so pregnant women breathe more deeply.

Oxygen consumption increases but arterial oxygen pressure does not change.