circulatory system part 2

Question 1

Arthropod heart:

5 characteristics?

Answer 1

heart pumps hemolymph out of arteries

blood returns via OSTIA durning diastole

valves in ostia open and close to regulate flow

the heart is sustended with a series of ligaments

the heart is neurogenic (contractioon in response to signals from nervous system)

Question 2

Cardiac cycle in arthropods:

neurons of cardiac ganglion undergo what?

Answer 2

spontaneous rhythmic depolarization

Question 3

Vertebrate hearts:

what are the complex walls with four main parts called?

Answer 3

Pericardium

Epicardium

Myocardium

endocardium

Question 4

What is the pericardium

Answer 4

sac of connective tissue that surrounds heart

outer(Parietal) and inner(visceral) layers

space between the layers filled with lubricating fluid

Question 5

What is the epicardium?

Answer 5

outer layer of heart, continuous with visceral pericardium

contains nerves that regulate heart and coronary arteries

Question 6

what is the myocardium?

Answer 6

layer of heart muscle cells (Cardiomyocytes)

Question 7

What is the endocardium?

Answer 7

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

Question 8

What are the two types of mycardium?

Answer 8

Compact - tightly packed cells arranged in regular pattern

spongy
-meshwork of loosely connected cells

Question 9

Caracteristics of myocardium in mammals, birds, and reptiles?

Answer 9

mostely compact

Question 10

characteristics of myocardium in fish and amphibians?

Answer 10

mostely spongy

arranged as trabeculae that extend into chambers

Question 11

Fish heart characteristics?

Answer 11

four chambers arranged in series

sinus venosus

atrium

ventricles

bulbus arteriosus

Question 12

Cardiac cycle of fish hearts?

Answer 12

serial contractions of chambers

valves are passive

opens and closes according to pressure differences

assure unidirectional flow of blood

noncontractile bulbus arteriosus serves as volume and pressure reservoir

Question 13

Amphibian Hearts:

Answer 13

Three chambers two atria one ventrical

Trabeculae in ventrical- helps prevent mixing of oxygenated and deoxygenated blood in ventrical

spiral fold in conus arteriosus
-helps direct deoxygenated blood to pulmocutaneous circuit and oxygenated blood to systemic circuit

Question 14

Reptile heart:

Answer 14

five chambered heart

two atria

threee interconnected ventricular compartments

cavum venosum-leads to systemic aortas

cavum pulmonale - leads to pulmonary artery

cavum arteriosum

seperation of oxygenated and deoxygenated blood in the venricle is nearly complete

Question 15

Shunting in reptile hearts:

right to left

left to right

Answer 15

Can shunt blood to bypass pulmonary or systemic circuit

right to left shunt- deoxygenated blood bypasses pulmonary circuit and enters systemic circuit
(during breath holding)

left to right shunt

oxygenated blood reenters pulmonary circuit
aids oxygen delivery to myocardium

Question 16

Bird and mammals hearts:

Answer 16

four chambers

two atria (thin walled)

two ventricles (thick walls, left ventricle thicker than right)

ventricles spereated by intraventricular septum

Question 17

Bird and mammals:

valves

Atrioventricular (AV) valves

Answer 17

between atria and ventricles

tricupid on right

Bicuspid or mitral on left

Question 18

Bird and mammals:

valves
Semilunar

Answer 18

between ventricles and arteries

AORTIC: between left ventrical and aorta

PULMONARY: between right ventricle and pulmonary artery

Question 19

Hearts:

Cardiac syscle- pumping action of the hearts

Answer 19

systolic - contraction , blood is forced out into the circulation

Diastole- relaxation

blood enters the heart

Question 20

Mammalian cardiac cycle:

Answer 20

atria and ventricals alternate systole and diastole

the two atria contract simultaneously

there is a slight pause

the two ventricales contract simultaneously

atria and ventricles relax while the heart fills with blood

Question 21

Ventricular pressure:

Answer 21

left ventricle contracts more forcefully and develops higher pressure

resistance in pulmonary circuit low due to high capillary density in parallel (large cross sectional area)

less pressure needed to pump blood through pulmonary circuit

low pressure protects delicate blood vessels of lung

Question 22

pressure in certebrate circulatory systems:

blood pressure in left ventricle changes with what?

Answer 22

changes is systolic and diastolic pressure

Question 23

pressure in certebrate circulatory systems:

pressure decreases when?

Answer 23

as blood moves through system

Question 24

ressure in certebrate circulatory systems:

pressure and pulse decrease in arterioles due to what?

Answer 24

due to increase in total cross sectional area

Question 25

ressure in certebrate circulatory systems:

velocity of blood is highest where and least where?

Answer 25

highest in arteries, lowest in capillaries and intermediate in veins

Question 26

Mean arterial pressure:

average arterial pressure in aorta over time?

Answer 26

MAP= 2/3 diastolic pressure + 1/3 systolic pressure

Question 27

Blood velocity:

Flow (Q)

Answer 27

volume of fluid transferred per unit time

Question 28

Blood velocity:

velocity?

Answer 28

distance per unit time

Question 29

Blood velocity:

=Q/A

Answer 29

A= cross sectional area of the vessel

velocity of flow is inversely related to total cross sectional area