BIOL 261 FINAL CHP 14

Question 1

Gases diffuse from:

Answer 1

HIGH to LOW concentration

Question 2

Boyle’s law states that:

Answer 2

Pressure is inversely related to volume

Question 3

Inspiration steps:

Answer 3

Diaphragm and intercostal muscle contact-> vol. of thoracic cavity increases-> pressure decreases-> air into lungs

Question 4

Expiration steps:

Answer 4

Diaphragm and intercostal muscle relax-> vol. of thoracic cavity decreases> pressure increases> elastic recoil of tissues> air out of lungs

Question 5

Residual volume

Answer 5

Air that reminds in the lungs

Question 6

Vital capacity

Answer 6

The max amount of air moved through the lungs

Question 7

FVC measures your:

Answer 7

Vital capacity when you forcefully exhale

Question 8

If your %FEV1 is <80% you have:

Answer 8

Obstructive pulmonary disease

Question 9

If your actual FVC is < predicted FVC you have:

Answer 9

Restrictive pulmonary disease

Question 10

If you have restrictive respiratory disease what is effected?

Answer 10

Alveolar surface is diminished

Question 11

If you have obstructive respiratory disease what is effected?

Answer 11

Bronchi are constricted/obstructed

Question 12

Alveoli:

Answer 12

Functional unit of lungs and site of gas exchange between respiratory and circulatory systems by DIFFUSION

Question 13

How is CO2 transported in the blood?

Answer 13

• 70% transported as carbonic acid
• 23% bound to amino groups of proteins in hemoglobin
• 7% transported as CO2 and dissolved in plasma

Question 14

Carbonic acid dissociates into:

2

Answer 14

H+ and bicarbonate (HCO3-)

-chloride ion shift

Question 15

Central chemoreceptors:

Answer 15

• located in medulla oblongata
• detects interstitial fluid CO2->pH
• monitors arterial CO2, cerebral blood flow and metabolism

Question 16

Peripheral chemoreceptors:

Answer 16

• located in carotid and aortic arteries
• detects arterial CO2->pH
• monitors alveolar ventilation

Question 17

Why can you hold your breath longer when you hyperventilate?

Answer 17

Because you are breathing more CO2 out

Question 18

Why can you not hold your breath as long when you breath into a bag?

Answer 18

Because you are breathing in the CO2 that is in the bag

Question 19

Alveoli produce:

Answer 19

Surfactant

Question 20

Respiratory negative feedback loop:

Answer 20

Stimulus: Increase in ppCO2
Sensor: Peripheral chemoreceptors in aortic arch/carotid sinus
Central chemoreceptors in medulla oblongata
Integrator: Medulla Oblongata
Effector: Diaphragm + external intercostal muscles
Response: Increase breathing rate and depth
Result: decrease ppCO2

Question 21

Why is oxygen released at the tissues?

Answer 21

Pressure in tissues is lower

Question 22

Carbon dioxide reaction:

CO2 + H20 ->

Answer 22

H2CO3-> H+ + HCO3-

Question 23

Carbonic acid and bicarbonate reaction:

Answer 23

CO2 + plasma-> carbonic acid-> H+ + bicarbonate ion

Question 24

How is oxygen transported in the blood?

Answer 24

via hemoglobin in the RBC’s or dissolved in plasma

Question 25

What happens when chemoreceptors adapt over time from excessive stimulation:

Answer 25

leads to a higher set point for CO2-> causing COPD