The Respiratory System

Question 1

List major structures which air/oxygen passes through during respiration.

Answer 1

1. Oral Cavity/Nasal Cavity - filters, humifies, moistens
2. Pharynx - passageway for food and air
3. Larynx
   
   1. Voice box w/ 2 vocal cords
   2. Passageway for air ONLY(gets covered by epiglottis when a person is swallowing food/drink)
   3. Sits below pharynx and in front of esophagus
4. Glottis - opening of the larynx
5. Trachea - Passagway for air ONLY, directs air to lungs
6. Bronchi
7. Bronchioles
8. Alveoli (major structure of gas exchange)
   
   1. Surrounded by a network of capillaries for O2 and CO2 gas exchange

Question 2

Major purposes of oral and nasal cavity

Answer 2

1. Filter (nasal cavity: goblet cell secete mucous trap small particles and vibrissae trap larger particles)
2. Humifies/Moistens (mucous from goblet cells provide moisture)
3. Warms Air (capillaries)

Question 3

Detergent that lowers surface tension and prevents alveoli from collapsing.

Answer 3

Surfactant

Question 4

Structures and function of Pleural Cavity.

Answer 4

Function: Protects lungs from injury and forms closed sacs on which lungs expand. Also indirectly connects lungs to chest wall, preventing them from collapsing during exhalation (like surfactant for alveoli)

1. Visceral Pleura - lines lung
2. Parietal Pleura - lines chest wall
3. Intrapleural Space
   
   1. B/t 2 membranes and contain a thin layer of fluid
   2. Lubricates pleural surfaces

Question 5

Explain Process of Inhalation.

Answer 5

1. External Intercostal muscles (lie between ribs) expand and diaphragm (thin muscular structure that divides thoracic cavity) flattens
   
   1. Together this increases intrathoracic volume
2. Intrapleural space increases in volume first - causes decreases in pressure
3. Lungs expand into intrapleural space - causes decrease in pressure.
4. Because air likes to move down its pressure gradient, air is sucked fom higher pressure environment to lower pressured lungs

Question 6

Tendency for air to rush into your lungs. due to it’s relative lower pressure compared to the atmosphere. (during inhalation)

Answer 6

Negative Pressured Breathing

Question 7

Active portion of breathing.

Answer 7

Inhalation

Question 8

Passive portion of breathing.

Answer 8

Exhalation

Question 9

Explain process of exhalation

Answer 9

1. External Intercostal muscles and diaphragm relax
2. Intrapleural space then lungs decrease in volume - causing both to increase in pressure
3. Air moves from now higher pressure thoracic cavity to lower pressured environmet (relative to thoracic cavity)

Question 10

Muscles used during forced (active) exhalation

Answer 10

1. Internal Intercostals
2. Abdominal muscles

(Together oppose external intercostals and pulls rib cage down, decreasing volume of thoracic cavity).

Question 11

Measures lung volume and capacity.

Answer 11

spirometer

Question 12

TLC (Total lung Capacity)

Answer 12

Maximum volume of air in lungs during inhalation.

Question 13

Residual Volume

Answer 13

Minimum volume of air in lungs during exhalation.

Question 14

Vital Capacity

Answer 14

Different between TLC and RV

Question 15

Tidal Volume

Answer 15

Volume of air exhaled/inhaled during a normal breath.

Question 16

ERV (Expiratory Reserve Volume)

Answer 16

Volume of additional air that can be forcibly exhaled after normal exhalation.

Question 17

Inspiratory Reserve Volume (IRV)

Answer 17

Volume of additional air that can be forcibly inhaled after a normal inhalation.

Question 18

Ventillation center that regulates ventilation.

Answer 18

Medulla Oblongata

Question 19

How does the medulla oblongata regulate ventillation?

Answer 19

Chemoreceptors in neurons of medulla oblongata

These are highly sensitive to CO2 and only sensitive to O2 during significant Hypoxemia

Question 20

What happens to the respiratory rate when CO2 increases?

Answer 20

RR increases so that CO2 is exhaled and CO2 levels in the blood fall.

Question 21

These chemoreceptors are located in the carotid arteries and aorta.

Answer 21

Peripheral chemoreceptors

Also monitor blood CO2 levels and increase RR when they become too high. The also mainly monitor oxygen concentration and PH.

Question 22

Hypercapnia/Hypercerbia

Answer 22

When pp of CO2 rises in the blood.

Question 23

What can hypoventillation lead to and how does our body response.

Answer 23

1. High levels of CO2
2. Rapid RR

Question 24

What can hyperventillation lead.

Answer 24

Reduced levels are CO2

Question 25

List major functions of the Respiratory System.

Answer 25

1. Gas Exchange 2. Thermoregulation 3. Immune Function 4. PH Regulation

Question 26

How are the lungs able to control thermoregulation?

Answer 26

Because the respiratory system is highly vascularized (i.e. capillaries within nose and trachea), it regulate thermoregulation via vasoconstriction and vasodialation.

Question 27

Respiratory system can also transfer heat to the enviroment during evaporation of ______ in _______ secretiosns.

Answer 27

1. H20 2. Mucous

Question 28

Major components involved in immune function of respiratory tract.

Answer 28

1. Lysozyme 2. Mucociliary Elevator 3. Macrophages 4. Mast Cells

Question 29

enzyme found in nasal cavity, tears, and saliva that attacks peptidoglican walls of gram positive bacteria.

Answer 29

Lysozome

Question 30

Engulf and digest pathogens. Signal the rest of the immune system that there is an invader.

Answer 30

Macrophage

Question 31

Cells that populate the lungs, have preformed antibodies on their surface, and release inflammatory chemicals that induce an immune response when it comes into contact with triggering substances.

Answer 31

Mast Cells

Question 32

Equation for bicarbonate buffer system.

Answer 32

Question 33

Optimal pH range for human body

Answer 33

7.35-7.45

Question 34

What happens when the blood pH is low and hydrogen ion concentration increases?

Answer 34

1. BBS equation shifs to the left, increasing CO2 concentration 2. This will increase RR and cause excess CO2 be exhaled, raising the blood pH 3. As more CO2 is exhaled, this will, agaim shift the equation to the left 4. This shift to the left will cause H+ ion in the blood to decrease (because of formation of H2O on the left side of the equation)

Question 35

What happens when the blood pH is high and CO2 concentration increases?

Answer 35

1. RR is slowed to allow for accumulation of CO2 2. This shifts the equation to the Right, allowing for H+ and bicarbonate ion concentrations to increase (thereby increasing decreasing pH of the blood)

Question 36

Why can't a spirometer measure total lung capacity? What can it measure?

Answer 36

* it cannot measure residual volume, which is one of the two components of total lung capacty (in addition to vital capacity) * spirometer can measure vital capacity