Respiratory System

Question 1

Ideal respiratory surface

Answer 1

• large in relation to volume of animal
• thin
• wet
• well supplied with blood
• contact with the source of oxygen (air or water)

Question 2

Upper respiratory tract

Answer 2

• nasal cavity
• pharynx

Question 3

Lower respiratory tract

Answer 3

• larynx
• trachea
• main, subsidiary bronchi
• bronchioles and alveoli
• associated blood vessels (pulmonary arteries and veins)

Question 4

Thoracic walls

Answer 4

• bony thoracic skeleton
• diaphragm
• intercostal muscles
• muscles of arms and abdomen

Question 5

Each lung has:

Answer 5

• 1 primary
• 2 (left) or 3 (right) secondary bronchi
• many smaller bronchi and bronchioles

Question 6

What kind of epithelium lines the alveoli?

Answer 6

simple squamous => forms thin layer for diffusion of oxygen and CO2

Question 7

Lungs before birth

Answer 7

“pond” area => gas exchange across placenta
lung maduration takes place last few wakes

Question 8

Thoracic cage

Answer 8

Protects lungs

Question 9

How many pairs of ribs?

Answer 9

12 + midline sternum

Question 10

Thoracic walls

Answer 10

Thoracic cavity must be expanded in all directions => bilaterally, superiorly/ inferiorly, anteroposteriorly

Question 11

What happens during INHALATION?

Answer 11

• external intercostal muscles pull RIBS UP toward 1st rib and this action also moves the ribs OUT and around the sternum forward
• DIAPHRAGM contracts + flattens (moves inferiorly)
• volume CHEST increases

Question 12

What happens during EXHALATION?

Answer 12

• lower ribs fixed by abdominal muscles
• ribs DOWN (pulled by internal intercostal muscles)
• diaphgram relaxes and moves UP
• volume of chest decreases

Question 13

Components of respiratory system

Answer 13

• rib cage + sternum
• intercostal muscles
• diaphgram (muscle)

Question 14

Left lung does not have

Answer 14

horizontal fissure