circulatory system part 2

Question 1

ostia

Answer 1

crustacean heart - hemolymph returns to the heart through these holes
contains valves that open and close to regulate the flow

Question 2

what controls the crustacean heart?

Answer 2

neurogenic

nervous system signals control contraction

Question 3

what is the cardiac cycle in arthropods

Answer 3

neutrons spontaneously depolarize causing cardiomycotes to contract
decreases volume of heart, increases pressure
valves in ostia close, forcing blood to leave through arteries
ligaments pull on walls of heart increasing volume and decreasing pressure
valves in ostia open, sucking blood into heart

Question 4

types of myocardium

Answer 4

mammal - compact

fish/amphibians - spongy

Question 5

how many layers does the pericardium have?

Answer 5

2 layers

Question 6

what are the four main parts of vertebrate heart walls?

Answer 6

pericardium
epicardium
myocardium
endocardium

Question 7

pericardium

Answer 7

sac of connective tissue that surrounds heart
outer (parietal) and inner (visceral) layers
- space between layers filled with lubricating fluid

Question 8

epicardium

Answer 8

outer layer of heart, continuous with visceral pericardium

contains nerves that regulate heart/ coronary arteries

Question 9

myocardium

Answer 9

layer of heart muscle cells - cardiomycotes
spongy - meshwork of loosely connected (fish/amphibians)
compact - tightly packed cells arranged regularly (mammals, birds reptiles)

Question 10

endocardium

Answer 10

innermost layer of connective tissue covered by epithelial cells (endothelium)

Question 11

four chambers of fish hearts

Answer 11

sinus venosus
atrium
ventricle
bulbous arteriosus

Question 12

fish heart cycle

Answer 12

passive valves open and close depending on pressure differences
unidirectional flow of blood
bulbous arteriousus does not contract but instead serves and pressure/ volume reservoir

Question 13

amphibian heart

Answer 13

3 chambered: 2 atria and 1 ventricle

Question 14

trabaculae - amphibian heart

Answer 14

in ventricle - helps prevent mixing of de/oxygenated blood

Question 15

spiral fold in conus arteriosus - amphibian heart

Answer 15

helps direct deoxygenated blood to pulmocutaneous circuit and oxygenated blood to systemic circuit

Question 16

reptile hearts

Answer 16

five chambered - 2 atria and 3 ventricles

Question 17

caveum venosum- reptile hearts

Answer 17

leads to systemic aortas

Question 18

caveum pulmonale

Answer 18

leads to pulmonary artery

Question 19

caveum arteriosum

Answer 19

third compartment of ventricle

Question 20

right to left shunt (reptile heart)

Answer 20

deoxygenated blood bypasses pulmonary circuit and enters systemic circuit
breath holding

Question 21

left to right shunt

Answer 21

oxygenated blood reenters pulmonary circuit

helps oxygen delivery to myocardium

Question 22

bird and mammals hearts

Answer 22

four chambers:
2 thin walled atria
2 thick walled ventricles

Question 23

intraventricular septum - birds and mammals

Answer 23

separates ventricles

Question 24

atrioventricular valves

Answer 24

between atria and ventricles
tricuspid - right
bicuspid (or mitral) - left

Question 25

semi lunar valves

Answer 25

between ventricles and arteries
aortic - left ventricle and aorta
pulmonary - between right ventricle and pulmonary artery

Question 26

phases of cardiac cycle (mammal heart)

Answer 26

systole 
- contraction
- blood forced out
diastole
- relaxation
- blood enters the heart

Question 27

mammalian cardiac cycle

Answer 27

1. ventricular diastole
2. atrial systole
3. ventricular systole (isovolumetric)
4. ventricular systole (ventricular ejection)
5. ventricular diastole

Question 28

pressure in ventricles

Answer 28

left ventricle - contracts forcefully, higher pressure

right ventricle - lower resistance, less pressure to protect delicate blood vessels

Question 29

velocity in blood

Answer 29

highest in arteries
middle in veins
lowest in capillaries

Question 30

mean average arterial pressure in aorta

Answer 30

2/3 diastolic pressure + 1/3 systolic pressure

Question 31

resisters in series

Answer 31

Rt= R1+R2

Question 32

resisters in parallel

Answer 32

1/Rt = 1/R1 +1/R2

Question 33

law of bulk flow

Answer 33

Q= P/R (pressure over resistance)

Question 34

diffusion rate

Answer 34

CAD/X

concentration x surface area x diffusion coefficient / distance