Respiratory System

Question 1

what is a respiratory surface?

Answer 1

one across which o2 and co2 are exchanged

Question 2

where does the swim (gas) bladder of fish lie?

Answer 2

above the gut (it develops as outgrowth of gut)

Question 3

from which part of the gut do the lungs develop?

Answer 3

the foregut

Question 4

which part of the germ layer does the lung lining come from?

Answer 4

gut endoderm

Question 5

which part of the germ layer do the surrounding tissues come from?

Answer 5

mesoderm

Question 6

how many pairs of ribs are there?

Answer 6

12

Question 7

how are the ribs attached to the sternum?

Answer 7

costal cartilages

Question 8

what type of cavities is the thorax divided into?

Answer 8

pleural cavities

Question 9

what separates the pleural cavities?

Answer 9

a central wall of tissue (mediastinum)

Question 10

what is each lung wrapped in?

Answer 10

pleura

Question 11

which layer is the visceral pleura?

Answer 11

inner layer

Question 12

what does the visceral pleura lie against?

Answer 12

the lung

Question 13

which layer is the parietal pleura?

Answer 13

outer layer

Question 14

what does the parietal pleura attach to?

Answer 14

the inside of the rib cage

Question 15

what does the pleural cavity contain?

Answer 15

lubricating fluid

Question 16

the pressure in the pleural cavity is positive. true or false?

Answer 16

false- it is negative

Question 17

what is another name for the root of the lungs?

Answer 17

the hilum

Question 18

the visceral and parietal pleura are continuous with one another at the hilum. true or false?

Answer 18

true

Question 19

how many lobes does the right lung have?

Answer 19

3 lobes

Question 20

what are the lobes of the right lung?

Answer 20

upper, middle and lower

Question 21

how many lobes does the left lung have?

Answer 21

2 lobes

Question 22

what are the lobes of the left lung?

Answer 22

upper and lower

Question 23

why is the left lung smaller than the right?

Answer 23

it fits against the cardiac notch

Question 24

what happens at the root of the lung?

Answer 24

structures enter or leave the lung

Question 25

what structures enter/leave the lung at the hilum?

Answer 25

one main bronchus, autonomic nerves, 1 pulmonary artery, 2 pulmonary veins.

Question 26

what supplies the alveoli with blood?

Answer 26

pulmonary artieries

Question 27

what is emphysema?

Answer 27

the thinning of the alveoli, loss of elastic tissue and collapse of small bronchioles and alveoli, therefore decrease in lung capacity

Question 28

where does gas exchange occur in an embryo?

Answer 28

placenta

Question 29

what is surfactant?

Answer 29

a chemical (lipid protein) that is secreted into the lungs and stops the alveoli collapsing

Question 30

when does most of lung maturation take place?

Answer 30

in the last few weeks of pregnancy

Question 31

describe the process of breathing in

Answer 31

volume of lungs increases, pressure decreases. therefore atmospheric pressure forces air into lungs. lungs expand until pressure is equal inside and out.

Question 32

describe the process of breathing out

Answer 32

volume of lungs decrease, pressure increase. therefore air forced out

Question 33

in what directions can the thoracic cavity expand?

Answer 33

bilaterally, superiorly/inferiorly, anteroposteriorly

Question 34

describe the movement of the respiratory system during inhalation.

Answer 34

first rib fixed by neck muscles (scalenes). EXTERNAL intercostal muscles pull ribs UPWARDS towards first rib. this action also moves ribs OUT and sternum FORWARDS. diaphragm CONTRACTS and FLATTENS.

Question 35

describe the movement of the respiratory system during exhalation.

Answer 35

lower rib fixed by abdominal muscles. INTERNAL intercostal muscles pull ribs DOWN. diaphragm RELAXES and returns to domed resting position.

Question 36

what is the diaphragm made of?

Answer 36

skeletal muscle and tendon

Question 37

what supplies the diaphragm?

Answer 37

left and right phrenic nerves

Question 38

how do the phrenic nerves lie in the body?

Answer 38

start in neck, travel through thorax to diaphragm