Anatomy & Physiology

Question 1

Auricle

Answer 1

corresponds to the primitive atrium of embryonic heart; on RIGHT atria; contains pectinate muscles

Question 2

Crista terminalis

Answer 2

in right atrium; where the pectinate muscle and the sinus venarum meet

Superior end marks the SA node

Question 3

Fossa ovalis

Answer 3

embryonic hole (foramen ovale) where blood freely passed through from the right atrium to the left atrium

monitored by the Eustachian tube/valve of inferior vena cava

Closes once the baby breathes air

Question 4

Papillary muscles

Answer 4

located in the right and left ventricles

responsible for closing the AV valves during systole to prevent regurgitation of blood into the atria

Question 5

Chordae tendinae

Answer 5

located in right and left ventricles

fibrous strands that connect the papillary muscles to the cusps of the AV valves

Question 6

Normal cardiac sounds

Answer 6

S1 (lub - low pitched) = start of systole = closing of the AV valves (tricuspid & mitral)
**heard loudest at the mitral valve area (5th intercostal)

S2 (dub - high pitched) = end of systole = closing of the pulmonary & aortic valves
(aka semilunar valves)

Question 7

Abnormal cardiac sounds

Answer 7

S3 = as the ventricle fills, heard EARLY in diastole; it is the sound of vibrations of the blood bouncing off the walls

S4 = heard at the time of atrial contraction, LATE in diastole during “atrial kick”; due to accelerated rush of blood into the ventricles

**both are low-frequency abnormal DIASTOLIC sounds that occur w/ rapid ventricular filling

Question 8

Pericardium (3 layers)

Answer 8

1. Fibrous pericardium - outer, thicker layer, resistant to stretch

Serous pericardium - secretes fluid between parietal & visceral layer

2. Parietal layer
3. Visceral layer - adheres to heart muscle itself

Innervated by the phrenic nerve

Question 9

Pericardial friction rub

Answer 9

decreased fluid between the visceral and parietal layer, increasing roughness, causing friction & vibrations that can be heard w/ each cardiac cycle
(sounds like squeaky leather)

typically due to viral infections

Question 10

Rib movement during ventilation

Answer 10

Upper ribs = pump handle (upward and forward)

Lower ribs = bucket handle (upward & outward)

Question 11

Muscles of inspiration

Answer 11

Primary = diaphragm (+ external & interchondral intercostals to elevate ribs (quiet))
- greatest excursion in supine

Accessory = scalenes, SCM (forced)

Question 12

Muscles of expiration

Answer 12

Primary = PASSIVE recoil of lungs & thoracic cage (quiet)

Accessory = abdominals (depress lower ribs), internal intercostals (forced)

Question 13

Pleura and Pleural cavity

- abnormalities

Answer 13

Pleural cavity is the space between the visceral & parietal pleura, containing fluid to prevent irritation/friction

• visceral pleura: adhere to surface of the lung
• parietal pleura: line the wall of pleural cavity

In abnormal circumstances the pleural cavity may contain air (pneumothorax), blood (hemothorax), pus, or increased amounts of serous fluid, compressing the lung and causing respiratory distress

Question 14

Pulmonary ligament

Answer 14

Not a true ligament; it is a extra reflection of the pleural membrane that adheres onto eachother and attaches to the lung inferior to the hilar region

provides some added stability

Question 15

Bronchopulmonary segment

Answer 15

Each bronchi, pulmonary artery & vein of a segment of a lung
(8 in left, 10 in right)

important to know for postural drainage

Question 16

Innervation of the Heart

- autonomic NS regulation

Answer 16

PNS control - Vagus nerve - release of acetylcholine to slow the HR
- cholinergic receptors

SNS control - sympathetic nerves, T1-T5 - release of epinephrine & norepinephrine to increase the HR and increase force of contractility
- adrenergic receptors (alpha & beta)

Question 17

Stroke Volume

- normative values

Answer 17

amount of blood pumped out of the ventricle/beat

Calculation: end diastolic volume MINUS end systolic volume
OR ejection fraction/end diastolic volume

Norm @ rest = 70mL/beat
Norm w/ exercise = 100-200mL/beat

Question 18

Cardiac output

- normative values

Answer 18

amount of blood pumped out of the heart per minute

Calculation = SV x HR

Norm @ rest = 5L/min
Norm w/ exercise = 20L/min

Question 19

A-V O2 difference

- normative values

Answer 19

gas exchange in the periphery; the difference in the amount of oxygen in the arterial blood versus the amount in the venous blood

Norm @ rest = 15
Norm w/ exercise = 5

affects the VO2, determines how efficient your periphery is at extracting and utilizing O2 during exercise

Question 20

Ejection Fraction

- normative values

Answer 20

proportion of the blood pumped out of the ventricles per beat (what percent of the blood that is in the heart at the end of diastolic filling is actually pumped out)

Calculation = SV/EDV

Norm = 60-70%
CMD = 30-40%
CHF = less than 30%

Question 21

Anaerobic threshold

Answer 21

corresponds to how efficient your periphery is at removing waste products during exercise;

this relates to the rise in CO2 disproportionate to the rise in O2

can increase the efficiency of removing byproducts by doing interval training

Question 22

Respiratory Exchange Ratio

Answer 22

Volume of CO2/Volume of O2

Determines what your body is using for fuel & if it is aerobic or anaerobic metabolism

.5 = carbs & fats
.75 = predominantly carbs
> 1.0 = anaerobic metabolism (corresponds w/ anaerobic threshold)
> 1.1 = max effort

Question 23

Control of Ventilation: Regulatory centers

- three areas they receive and integrate info from…

Answer 23

insp/exp centers in medulla… determine rate & depth of breathing

1. Chemoreceptors in brain, carotid body and aorta detect changes in Co2 and O2 levels –> inc/dec RR
2. Sensors in alveoli detect fluid in tissue –> increase RR, decrease depth
3. Mechanoreceptors in periphery (joint/muscles) detecting physical activity –> inc RR and depth

Question 24

Vesicular breath sound

Answer 24

normal breath sound that is soft and quiet, heard over the entire lung surface EXCEPT beneath the manubrium and in the interscapular region

• inspiration is longer than expiration

Question 25

Bronchial (tubular) breath sound

Answer 25

normal breath sound that is loud and course, resulting from compression of the pulmonary tissue that assists in the transmission of sound from the bronchial tree; only normal if heard directly over the trachea

• if heard in the lung surface it is ABNORMAL
• expiration is longer than inspiration