Physiology

Question 1

Nerve: major output of the PNS

Answer 1

Vagus n./CN X – feeds thorax and upper abdomen (75% of nerve fibers)

Question 2

Describe the nerve structure of the SNS

Answer 2

Nerves pass from SC into paravertebral chain ganglions and on to post-ganglionic nerves that reach the viscera

Reenter via gray rami

Question 3

Spinal Level: pre-ganglionic cardiac and pulmonary sympathetic fiber origin

Answer 3

T1-5

Question 4

List the NTs for the PNS and SNS

Answer 4

PNS: Acetylcholine/Cholinergic (post-ganglionic)

SNS: Norepinephrine/Adrenergic (post-ganglionic)

Question 5

List the function of the cholinergic and adrenergic NTs

Answer 5

Cholinergic = calming/relaxing

Adrenergic = gear up the system

Question 6

List the subtypes of cholinergic NTs

Answer 6

• Muscarinic (post-synaptic and effector)
• Nicotinic (pre/post-synaptic in ANS)

Question 7

List the subtypes of Adrenergic NTs

Answer 7

Alpha 1 = vascular smooth mm; vasocon (PNS)

Alpha 2 = decrease SNS discharge (PNS)

Beta 1 = atria, SA node, ventricles (SNS)

Beta 2 = bronchial smooth mm; bronchodil (SNS)

Question 8

Term: breathing

Answer 8

pulmonary ventilation

Question 9

Describe how air move in/out with inspiration/expiration

Answer 9

Inspiration: diaphragm contracts and is pulled down, the increased volume of the lung decreases the pressure in the lungs and air flows from the high pressure (environment) to the low pressure (lungs)

Expiration: diaphragm recoils and moves up, the decreased volume of the lungs increaes the pressure in the lungs and air flows from the high pressure (lungs) to the low pressure (environment)

Question 10

Term: difference between the amount of oxygen in the arterial and venous systems

Answer 10

A-V O2 difference

Question 11

Term: where gas exchange does not occur

Answer 11

Anatomic dead space

Question 12

Term: volume of air normally exhaled/inhaled per breath

Answer 12

Tidal Volume (V_T)

Question 13

Term: Additional volume take in (beyond tidal volume)

Answer 13

Inspiratory reserve volume (IRV)

Question 14

Term: Additional volume let out (beyond tidal volume)

Answer 14

Expiratory reserve volume (ERV)

Question 15

Term: Volume of air that remains in the lungs after a forceful expiratory effort

Answer 15

Residual volume (RV)

Question 16

Describe what would occur if you had not RV

Answer 16

You lungs would collapse

Question 17

Describe what happens to RV in conditions like chronic bronchitis and emphysema

Answer 17

Air trapping increases RV

Question 18

Term: Maximum amount of air that can be inhaled after a normal tidal exhalation; V_T + IRV

Answer 18

Inspiratory capacity (IC)

Question 19

Term: amount of air remaining in the lungs at the end of a normal tidal exhalation; ERV + RV

Answer 19

Functional residual capacity (FRC)

Question 20

Describe what FRC represents

Answer 20

The point at which the forces tending to collapse the lungs are balanced against the forces tending to expand the chest wall

Question 21

Term: maximum amount of air that can be exhaled following a maximum inhalation, IRV + ERV

Answer 21

Vitcal capacity (VC)

Question 22

Term: product of tidal volume and respiratory rate

Answer 22

Minute ventilation V_E

Question 23

Term: amount of air blown out over time

Answer 23

Forced expiratory volume (FEV)

Question 24

Term: amount of air blown out in the 1st second

Answer 24

FEV1

Question 25

Term: maximum volume of air exhaled from a full inhalation (exhaling as forcefully as you can)

Answer 25

Forced vital capacity (FVC)

Question 26

List FEV, FVC, and FEV/FVC ratios

1. normal
2. obstructive disease
3. restrictive disease

Answer 26

1. FEV = 4.0; FVC = 5.0; 80%
2. FEV = 1.3; FVC = 3.1; 42%
3. FEV = 2.8; FVC = 3.1; 90%

Question 27

Explain why the FEV/FVC ratio is high for restrictive disease and low for obstructive disease

Answer 27

High: b/c you have a hard time getting air in; but they can get air out

Low: b/c you can’t get all the air out

Question 28

List the normal values

1. pH
2. HCO3
3. PCO2

Answer 28

1. 7.4
2. 22-26 mEq/L (high = basic)
3. 35-45 mmHg (high = acidic)

Question 29

Describe the carbonic acid-bicarbonate buffering system

Answer 29

The body can compensate for altered pH through 2 systems

1. lungs: blow off/hold CO2 (short term)
2. kidneys: absorb/regenerate bicarb (long term)

Question 30

Describe control of ventilation

Answer 30

2 main regulatory centers: medullary inspiration and expiration center establish rate and depth of breathing

The cortex can override these centers for active expiration

Question 31

Receptor location: detect CO2 or O2 levels in the blood

Answer 31

Brain, carotid bodies, aortic bodies

** result in inc/dec rate of breathing

Question 32

Receptor location: detect increased fluid in lung tissue

Answer 32

Alveoli

** result: rapid, shallow breathing

Question 33

Receptor location: detect physical activity

Answer 33

Joints/mm

** Result in inc breathing rate

Question 34

Type of receptor: sensitive to changes in PO2, PCO2, H+

Answer 34

Peripheral chemoreceptors

Question 35

Type of receptor: sensitive to acute stretch of alveoli, act as a safety mechanism to decrease duration of inspiration

Answer 35

lung receptors

Question 36

Type of receptor: sense movement in skeletal mm

Answer 36

mechanical receptors

Question 37

REVIEW METABOLIC/RESPIRATORY ACIDOSIS/ALKYLOSIS CHART

Answer 37

YOU’LL DO IT

Question 38

Term: an abnormally low concentration of oxygen in the blood

Answer 38

hypoxemia

Question 39

Term: deficiency in the amount of oxygen reaching the tissues

Answer 39

hypoxia