Circulation

Question 1

Gastrovascular cavities

Answer 1

Digestion and distribution of substances throughout the body

Simple animals such as cnidarians

Question 2

Circulatory system components

Answer 2

Circulatory fluid (blood)
Tubes (blood vessels)
Muscular pump (heart)

Question 3

Open circulatory system

Answer 3

Insects, arthropods, most molluscs
Blood bathes organs directly
Valves keep hemolymph going in right direction
Advantage: all cells are directly exposed to hemolymph

Question 4

Hemolymph

Answer 4

Exchange fluid in open circulatory system

Question 5

Closed circulatory system

Answer 5

Blood is confined to vessels and is distinct from interstitial fluid
More efficient at transporting circulatory fluids to tissues and cells
Advantage: concentrate blood in specific areas- move particles more efficiently

Question 6

Interstitial fluid

Answer 6

Completes exchange between blood and cells

Question 7

Cardiovascular system

Answer 7

Vertebrate closed circulatory system

Blood vessels and 2-4 chambered heart

Question 8

Arteries

Answer 8

Carry blood to capillaries away from heart

Question 9

Veins

Answer 9

Return blood from capillaries to heart

Question 10

Capillaries

Answer 10

Most direct contact with cells

Exchange of substances between blood and interstitial fluid

Question 11

Double circulation

Answer 11

2 trips to heart before going to rest of body

Pulmonary circuit and systemic circuit (rest of body)

Question 12

Ventricle

Answer 12

Pumps blood out of heart

Question 13

Atrium

Answer 13

Pumps blood into heart

Question 14

Fish circulatory system

Answer 14

2 chambered heart: 1 ventricle and 1 atrium
Single circulation
Ventricle -> artery -> gill capillaries -> systemic capillaries -> vein -> atrium

Question 15

Amphibian circulatory system

Answer 15

3 chambered heart: 2 atria and 1 ventricle
Double circulation
Pulmocutaneous: breathe through skin
Ventricle pumps blood into forked artery- splits ventricle’s output into pulmocutaneous circuit (oxygen-poor blood) and systemic circuit (oxygen-rich blood)

Question 16

Reptile circulatory system

Answer 16

Double circulation
Turtles, snakes, and lizards: 3 chambered heart
Extra vessel from ventricle: bypass lungs, allowing animal to swim for prolonged periods of time

Question 17

Mammalian and avian circulatory system

Answer 17

Ventricle is completely divided into separate right and left chambers
Left side of heart pumps and receives only oxygen-rich blood
Right side of heart pumps and receives only oxygen-poor blood

Question 18

4-chambered heart and endothermic lifestyle

Answer 18

Increased oxygen input- needed for oxidative phosphorylation (O2 is final electron receptor in electron chain)

Question 19

Mammalian circulatory pathway

Answer 19

Right ventricle -> pulmonary artery -> lung capillaries (diffusion of oxygen) -> pulmonary vein -> left atrium -> left ventricle -> aorta -> systemic capillaries -> vena cava -> right atrium

Question 20

Atrioventricular valves

Answer 20

Separate atria from ventricles

Question 21

Semilunar valves

Answer 21

Separate ventricles from arteries

Question 22

Systole

Answer 22

Pumping or contraction phase of cardiac cycle

Question 23

Diastole

Answer 23

Relaxation or filling phase of cardiac cycle

Question 24

Cardiac cycle

Answer 24

1. Atrial and ventricular diastole: AV valves open, semilunar valves closed
2. Atrial systole and ventricular diastole
3. Atrial diastole and ventricular systole: AV valves closed, semilunar valves open

Question 25

Self-excitable

Answer 25

Some cardiac muscle cells | Contract without any signal from the nervous system

Question 26

Sinoatrial (SA) node

Answer 26

Pacemaker: sets rate and timing for cardiac muscle cell contraction Influenced by nerves, hormones, body temperature, and exercise

Question 27

Heartbeat

Answer 27

1. SA node generates wave of signals to contract 2. Signals are delayed at AV node 3. Signals pass to heart apex and then Purkinje fibers 4. Ventricles contract

Question 28

Heart sounds

Answer 28

AV valve recoil: "lub" | Semilunar valve recoil: "dub"

Question 29

Electrocardiogram (EKG)

Answer 29

Displays electric impulses that travel through the cardiac cycle

Question 30

Blood vessels

Answer 30

Infrastructure of circulatory system Cavity: central lumen Valve in veinous lumen: prevent backflow 3 layers (inside to outside): Epithelium (endothelium), smooth muscle, connective tissue

Question 31

Skeletal muscle

Answer 31

Aids in veinous blood flow

Question 32

Velocity of blood flow

Answer 32

Varies in the circulatory system | Slowest in capillaries: high resistance and large cross-sectional area to allow diffusion

Question 33

Blood pressure

Answer 33

Hydrostatic pressure that blood exerts against the wall of a vessel

Question 34

Systolic pressure

Answer 34

Pressure in arteries during ventricular systole | Highest pressure in arteries

Question 35

Diastolic pressure

Answer 35

Pressure in arteries during diastole | Lower than systolic pressure

Question 36

Measuring blood pressure

Answer 36

Cuff puts pressure against an artery (almost cutting off blood flow): measure systolic Slowly release pressure: measure diastolic

Question 37

Distribution of blood in capillary beds

Answer 37

Contraction of smooth muscle layer in wall of arteriole (small branch of artery) constricts vessel Precapillary sphincters control the flow of blood between arterioles and venules: open- blood flow into capillaries, closed- blood flow only between arterioles and venules

Question 38

Atherosclerosis

Answer 38

Buildup of cholesterol within arteries

Question 39

Hypertension

Answer 39

High blood pressure | Promotes atherosclerosis and increases risk of heart attack or stroke

Question 40

Heart attack

Answer 40

Death of cardiac muscle resulting from blockage of one or more coronary arteries

Question 41

Stroke

Answer 41

Death of nervous tissue in the brain | Usually results from rupture or blockage of arteries in head