Frog heart lab

Question 1

What are the three biggest morphological differences between frog and human hearts?

Answer 1

Frog hearts are three chambered, frog hearts use Sinus venosus in order to channel O2/nonO2 rich blood and Pacemaker activity, No coronary circulation

Question 2

What is overdrive suppression?

Answer 2

When the faster pacemaker cells suppress the slower ones

Question 3

What are the refractory periods of cardiac tissue?

Answer 3

Effective: the absolute refractory period of the n.s
relative: the time strait after a contraction when stimulation can occur at higher voltages

Question 4

Do VA or SA tissue in the heart have plateau phases?

Answer 4

VA due to Ca+ influx

Question 5

What are the four phases of the cardiac cycle and which ones are systole and diastole?

Answer 5

1) ventricular filing (diastole)
2) isovolumetric contraction (systole)
3) ventricular ejection (systole)
4)isovolumetric relaxation (diastole)

Question 6

What is systole and what is diastole?

Answer 6

Systole: contraction and emptying
diastole: relaxation and filling

Question 7

Which valves are open and which are closed during the four phases of the cardiac cycle

Answer 7

1) ventricular filling: AV valve open, semilunar close
2) isovolumetric contraction: All valves close
3)Ventricular ejection: Semilunar valves open and allow for the blood to be released
4) isovolumetric relaxation: All valves close

Question 8

What is the Frank-Starling Law of the heart?

Answer 8

the more the heart is filled during diastole, the harder it will contract during systole

Question 9

What is the sympathetic hormone for the heart and it’s receptor.

Answer 9

ACh and its receptor mAChR

Question 10

What is vegal escape?

Answer 10

When other pacemaker cells take over when the SA node is being weird

Question 11

What is epinephrine a ligand of (receptor)?

Answer 11

beta-adrenergic (in heart) (alpha in vascular)

Question 12

What is auscultation?

Answer 12

Using artery sound to find BP

Question 13

What are korotkoff sounds?

Answer 13

the ‘tapping’ made during occluded arteries make during turbulent blood flow

Question 14

What is the formula for pulse pressure? Mean arterial pressure?

Answer 14

MAP: the average effective pressure that drives blood
MAP = CO * TPR = 1/3SBP + 2/3DBP
PP= SPB -DPB

Question 15

What is stroke volume? How does it compare to cardiac output?

Answer 15

Stroke volume is the volume of blood released in a single beat
Cardiac Output: volume of blood pumped in a minute
CO = HR * SV

Question 16

What is total peripheral resistance?

Answer 16

Overall resistance to flow through the entire systemic circulation

Question 17

Which one (v. or a.) has muscle?

Answer 17

arteries

Question 18

What percentage of blood is in the veins?

Answer 18

around 70%

Question 19

What is pulse pressure?

Answer 19

the difference between systolic and diastolic blood pressure

Question 20

what is normal human blood pressure

Answer 20

120/80 mmHg

Question 21

What is the equation of blood flow (in vol/time)

Answer 21

Q= pressure difference/resistance

Question 22

what is regulated and what is changed: pressure and resistance? What is the mechanism of regulation

Answer 22

resistance is changed (via arterial radius) and pressure is regulated

Question 23

Which have more compliance? v. or a.

Answer 23

veins

Question 24

What is pressure regulated by (2)?

Answer 24

volume of blood in vessel and compliance

Question 25

which have more capacitance, a v. with a high compliance or a low one?

Answer 25

high

Question 26

What causes volume change in a. versus v.?

Answer 26

a: increased SV, CO, HR or arterial resistance
v: decrease in HR, changing in body position

Question 27

What is hydrostatic pressure? When and where does it occur in the body?

Answer 27

hydrostatic pressure is pressure build up by heigh difference. This occur in the circulatory system when the body is upright, giving greater pressure below the heart and lesser pressure above

Question 28

What is the hydrostatic reflex that keeps BP at normal levels?

Answer 28

BP drops -> baroreceptors detect -> medulla increases firing rate -> HR increases -> BP increases

Question 29

where are the baroreceptors located?

Answer 29

Carotid sinus and aortic arch

Question 30

What does norepinephrine do when it binds to alpha-adrenergic receptors in v.? how about a.?

Answer 30

Both experience vasoconstriction
a: increases resistance and decreases venous flow
v: increases pressure and increases venous flow/return

Question 31

what hormone is norephinephrine (sympathetic or para)?

Answer 31

sympathetic

Question 32

what happens when norephinephrine binds to the beta-adrenergic receptors

Answer 32

increases HR and contractility (SV, and CO)

Question 33

What type of hormone is acetyl choline (sympathetic or para) and what receptor does it bind to?

Answer 33

acetylcholine is parasymapathetic and binds to muscarinic AChR

Question 34

What are the parasympathetic effects on the heart (3)?

Answer 34

decrease HR, Decrease in CO, decrease in BP

Question 35

Difference between reactive and active hyperemia?

Answer 35

reactive: reaction to increased metabolites in tissues with poor blood flow. Causes vasodilation
active: increased blood flow caused by increased metabolic activity