Cardiorespiratory Physiology

Question 1

What does the respiratory system do

what does the cardiovascular system do

pulmonary ventilation

how to expire air and inspire
passive?

Answer 1

The respiratory system ensures the delivery of
oxygen from the environment into the alveoli and the
bloodstream, and the elimination of carbon dioxide
from the blood into the alveoli and the environment
(gas exchange).

The cardiovascular system brings oxygenated arterial
blood from the heart to the skeletal muscles and
back

Pulmonary ventilation describes the process of moving and exchanging ambient air with air in the lungs

As inspiratory muscles contract, thoracic cavity/lung volume increases, lowering pressure to below atmospheric pressure and causing air to flow in

At rest, expiration is largely passive, resulting from lung recoil and relaxation of inspiratory muscles
* At higher exercise intensities, expiratory muscle contraction assist in expiration

Question 2

Minute ventilation, tidal volume, at rest and max

Hypernea

hyperventilation

dyspnea

Answer 2

Minute ventilation (VE) = Volume of air breathed per minute - - Tidal Volume (L) x breathing frequency (breaths per minute)
* At rest = 6L/min
* At maximal intensities = 160+ L/min

Hyperpnea generally refers to an increase in ventilation that occurs during physical activity

Hyperventilation refers to an increase in pulmonary ventilation that exceeds the oxygen consumption and carbon dioxide elimination needs of metabolism

Dyspnea refers to an inordinate shortness of breath or subjective distress in breathing

Question 3

each constituent of gas has a what

Answer 3

a partial pressure
partial pressure = percentage of concentration of specific gas x total pressure

Question 4

pulmonary ventilation and function of gas exchanges

alveoli surface area

The rate of gas diffusion into a fluid depends on:

how does the blood carry oxygen, how much(mL/blood)

how does th blood carry carbon dioxide

Answer 4

Pulmonary ventilation describes the process of moving and exchanging ambient air with air in the lungs

1. O2 binding (during inspiration)
2. CO2 release (during expiration)

Alveoli surface area: 70-80 m2 in an adult

• The pressure differential between the gas above the fluid and the gas dissolved in the fluid
• The solubility of the gas in the fluid
  AND THE CONCENTRATION OF GASES

carries it in hemoglobin on the 4 heme groups and a bit dissolved in the plasma, at rest about 20mL O2 / 100mL

at high intensities carbon dioxide production increases, and some CO2 combines with Hb and most is carried as bicarbonate

Question 5

Air comes into the trachea, why does partial pressure drop a bit process of air coming in and out of tissus and capillaries

the gas always progresses from high to low partial pressure, or concentration

Answer 5

vapor pressure in the trachea displaces some of the gas molecules in the air.

Oxygen go into low concentration to arteries, then passing the muscle tissues, oxygen goes in and carbon dioxide comes out into the veins then brings CO2 to be expired

Question 6

hemoglobin saturation

bohr affect and how that changes hemoglobin saturation

at muscles, what is the environment

Answer 6

Steeper(left): Higher HbO2 affinity
Lower CO2
higher pH
lower temperature
** less pressure(saturation) is needed to saturate the Hb with O2**

Less steep(right): Reduced HbO2 affinity
Higher CO2
Lower pH
Higher Temperature
** More pressure is needed to saturate the Hb with O2**

at the muscles have a reduced HB affinity environment

Question 7

heart, what side gets what

left ventricular wall

the nodes and processes

how is it regulated

Answer 7

Right side:
* Atrium receives deoxygenated blood from body
* Ventricle pumps deoxygenated blood to lungs
Left side:
* Atrium receives oxygenated blood from lungs
* Ventricle pumps oxygenated blood to body

left ventricular wall is thicker to be stronger to pump oxygenated blood around the entire body and contract more forcefully

SA node acts as the pacemaker
SA node → Atria → AV node → AV bundle
→ Purkinje fibers → Ventricles

regulated by the brain and the sympathetic(increase) nervous system and the parasympathetic(decrease)

Question 8

cardiac output
how can the same cardiac output be achieved

Answer 8

Q = HR x SV

HR = number of beats per minute
SV = amount of blood ejected from the left ventricle

the same Q can be made by High HR and Low SV
or low HR and high SV

training can increase SV and decrease HR

Question 9

total blood flow volume

where does it go during rest
how it changes during excercise

Answer 9

total blood volume is 5L on average

At rest, ∼80% of cardiac output is directed
to the brain, heart, kidneys, and liver

• During exercise, blood flow to active
  skeletal muscle can increase ∼100 times
  above resting levels levels
• Can account for up to 80%–90% of CO,
  while blood flow to other tissues is
  reduced.

Question 10

during equation, what happens to ATP turnover and ADP
muscle oxygen usage

Answer 10

At maximal intensities, ATP turnover may
exceed 100x that at rest!

• Oxygen consumption may increase 10-15
  fold (or more for elite endurance athletes!)
• ATP + H2O → ADP + Pi
• Increases in ADP as a result of ATP breakdown are the primary signal for increasing oxidative phosphorylation
• Increases in skeletal muscle blood flow and oxygen utilization in the tissues will then facilitate increased delivery to tissues

Question 11

how oxygen difference changes during exercise at capillaries

Fick equation

Answer 11

there will be a larger difference between oxygen content in arteries and veins

at rest CO = ~ 5 L/min
During maximal exercise CO = ~20 L/min

• SV increased via increased diastolic filling
• Fick Equation:
• VO2 = Q x a-vO2 diff
• VO2 = 5 L blood/min x 5 ml O2 /100 ml blood = 250 ml O2/min (~3.6 ml O2/kg/min for 70kg individual)
• During maximal exercise
• VO2 = 20 L blood/min x 15 ml O2 /100 ml blood = 3000 ml O2/min (~42.9 ml O2/kg/min for 70kg
  individual)