Respiratory system

Question 1

What is the major function of the respiratory system

Answer 1

the major function is to supply the body with oxygen and get rid of carbon dioxide

Question 2

what side of the lungs have 3 lobes

Answer 2

right side

Question 3

what is the dorsal respiratory group ? (DRG)

Answer 3

the DRG controls the basic rhythm of breathing by triggering inspiratiory impulses.
these neurons send impulses to the motor neurons of the diaphragm and external intercostal muscles

Question 4

describe the process of expiration

Answer 4

1- inspiration muscles relax

2- the size of the thoratic cavity decreases

3- lungs recoil and intrapulmonary volume decreases

4- intrapulmonary pressure rises

5- air flows out of the lungs and down the pressure gradient until intrapulmonary pressure is 0

Question 5

describe the process of inspiration

Answer 5

1- muscles contract

2- the size of the thoracic cavity increases

3- lungs stretch and intrapulmonary volume

4- intrapulmonary pressure drops

5- air flows into the lungs down the pressure gradient until the pressure is 0

Question 6

what is the boyle’s law

Answer 6

the action of inspiration and expiration- the pressure of a set mass of gas is inversely proportional to its volume at a constant temperature

Question 7

what are the two phases of pulmonary ventilation

Answer 7

inspiration (breathing in- active process)

expiration (breathing out- passive process)

Question 8

describe the mechanism of breathing

Answer 8

completely mechanical process and depends on volume changes in the thoracic cavity

volume changes lead to pressure changes which leads to the flow of gases to equalises pressure

Question 9

how have the lungs become adapted for immune support

Answer 9

hairs in nasal passage which traps debris
lymphoid tissues (tonsils)
cilia (hair like projections) beats towards the throat
mucus
additional defences- cough and sneezing to remove irritants

Question 10

what does the alveoli have a good blood flow

Answer 10

optimum blood flow for gaseous exchange is obtained by ventilation/ perfusion matching

Question 11

why does the alveoli have a thin membrane

Answer 11

allows rapid diffusion of gases

Question 12

give 3 structures of the alveoli

Answer 12

thin membranes
large surface area
good blow flow

Question 13

what is the parietal pleura

Answer 13

the portion of the protective tissues that lines the inner surface of the chest wall and covers the diaphragm

Question 14

what is the visceral pleura

Answer 14

the portion of the protective tissues that is attached directly to the lungs

Question 15

name the 2 layers of the pleura

Answer 15

visceral

parietal

Question 16

how many layers does the pleura have

Answer 16

2

Question 17

what is the pleura

Answer 17

it consist of a closed sac of serous membrane, one of each lung which contains a small amount of serous fluid

Question 18

what side of the lungs have 2 lobes

Answer 18

left

Question 19

what is the pontine respiratory group

Answer 19

control centres in the pons modify the rate and depth of breathing establisehd by the medulla

Question 20

what are the three factors that affect o2 and co2 transport across the respiratory membrane

Answer 20

Partial pressure gradients
Ventilation-perfusion coupling
Structure of respiratory membrane

Question 21

what is the henry’s law

Answer 21

“At a constant temperature, the amount of a given gas that dissolves in a given type and volume of liquid is directly proportional to the partial pressure of that gas in equilibrium with that liquid.”

Question 22

what is diffusion

Answer 22

This is where gases diffuse down a concentration gradient (from an area of high gas concentration to an area of lower gas concentration) until they are equally distributed

Question 23

what is the respiration components for cellular respiration

Answer 23

Oxygen + Glucose ENERGY (ATP) + Carbon Dioxide + Water

Question 24

what is ventilation- perfusion coupling

Answer 24

Ventilation (V) refers to the flow of air into and out of the alveoli, while perfusion (Q) refers to the flow of blood to alveolar capillaries

Question 25

how is oxygen transported around the body

Answer 25

Oxygen is carried to the tissues as oxyhaemoglobin in red blood cells

Question 26

how does oxygen become oxyhaemoglobin

Answer 26

Once an O2 molecule has bound to iron, it changes Haemoglobin shape. Making it easier for other O2 molecules to bind. When 4 O2 molecules are bound Haemoglobin is fully saturated

Question 27

how is carbon dioxide carried in the blood

Answer 27

Carbon dioxide is carried in blood to the lungs in 3 forms:

1. ~ 10 % Dissolved in plasma
2. 20 % Chemically bound to haemoglobin
3. 70% as bicarbonate ions in plasma

Question 28

how does a pulseoximeter work

Answer 28

measures the percentage of arterial haemoglobin saturated with oxygen

Question 29

what is airway resistance

Answer 29

Airway resistance is the resistance of the respiratory tract to airflow during inhalation and exhalation.
A small change in diameter has a huge effect on the resistance of an airway e.g. halving the radius of an airway would cause a 16-fold increase in resistance.

Question 30

what are the two autonomic nerves that control the diameter of the airway

Answer 30

parasympathetic system

sympathetic system

Question 31

what is the parasympathetic system

Answer 31

causes the smooth muscle in the airway to contract (bronchoconstriction) Unstressed situations

Question 32

what is the sympathetic system

Answer 32

causes the smooth muscle in the airway to relax (bronchodilation). Stressful situations require more air to meet increased oxygen consumption

Question 33

what is a tidal volume

Answer 33

the volume of air that is inhaled or exhaled in only a single such breath.

Question 34

what is a vital capacity

Answer 34

the maximum amount of air a person can expel from the lungs after a maximum inhalation, usually 4.5 - 5.5 L

Question 35

what is a dead space volume

Answer 35

– air that remains in conducting zone and never reaches the alveoli

Question 36

what is the total lung capacity

Answer 36

maximum amount the lungs can hold ~ 6L of air

Question 37

what is residual volume of air

Answer 37

the air after exhalation

Question 38

what is the minute volume of air

Answer 38

)- the total volume of gas entering (or leaving) the lung per minute. It is equal to the tidal volume (TV) multiplied by the respiratory rate (f).At rest, a normal person moves ~450 ml/breath x 10 breath/min = 4500 ml/min.