Lecture 11: Circulation (Midterm II)

Question 1

By which process do most gases move easily through membranes?

Answer 1

diffusion

Question 2

diffusion is used in what type of animals

Answer 2

single celled and small

Question 3

larger animals use what for the transport of gas and other materials

Answer 3

distributive systems

Question 4

most exchange of material in cells occur

Answer 4

across thin epithelial tissues

Question 5

what are the characteristics for diffusion to be viable

Answer 5

less than 10mm distance and one or two cell layers

Question 6

true or false: diffusion is possible in gastrovascular cavities

Answer 6

true

Question 7

both open and closed circulatory systems have three basic components

Answer 7

• a circulatory fluid (blood or hemolymph)
• set of tubes (blood vessels)
• muscular pump (heart)

Question 8

distributive systems use ______ through circulating blood to carry materials from one place to another efficiently

Answer 8

convection

Question 9

in insects, arthropods, and molluscs, blood bathes the organs directly in

Answer 9

open circulatory system

Question 10

the general body fluid in an open circulatory system

Answer 10

hemolymph

Question 11

in a closed circulatory system, blood is ______ to vessels and is ______ from interstitial fluid

Answer 11

confined; distinct

Question 12

closed or open systems are more efficient at transporting circulatory fluids to tissues and cells

Answer 12

closed systems

Question 13

the closed circulatory system humans and other vertebrates have is called the

Answer 13

cardiovascular system

Question 14

three main types of blood vessels

Answer 14

arteries, veins, capillaries

Question 15

arteries branch into ______ and carry blood to ______

Answer 15

arterioles; capillaries

Question 16

Networks of capillaries that are the sites of chemical exchange between blood and interstitial fluid

Answer 16

capillary beds

Question 17

venuoles converge into _______ and return what from the capillaries to the heart?

Answer 17

veins; return blood

Question 18

What are the 3 goals of circulation

Answer 18

1. gas exchange
2. energy balance
3. osmoregulation

Question 19

Gas Exchange

Answer 19

• deliver respiratory gases to the tissues in the body for cellular respiration
• remove gases that are a byproduct of cellular respiration to respiratory surfaces for disposal

Question 20

Energy balance in circulation

Answer 20

• deliver byproducts of digestion and absorption to the liver and other tissues for processing
• remove waste products of nutrient breakdown during cellular respiration to kidney for excretion

Question 21

Osmoregulation

Answer 21

carrying water, other ions, and signal molecules throughout the body

Question 22

Two plans of circulation

Answer 22

single circulation and double circulation

Question 23

single circuits (circulation)

Answer 23

blood is pumped to the respiratory surfaces so it can dump CO2 and pick up O2 for direct delivery to tissues; low pressure throughout

Question 24

double circuits

Answer 24

low & high pressure circuit;
low pressure circuit: blood is pumped from heart to the lungs for exchange of gases
high pressure circuit: blood is pumped from heart through the body for delivery of gases to tissues

Question 25

single circuit vs double circuit

Answer 25

single circuits have slow delivery due to low pressure, so its found in animals with low metabolic rates; double circuits will have constant delivery due to high pressure, so it's found in more active animals with high metabolic rates & even high body temperatures

Question 26

Explain how blood and oxygen are distributed in a two circuit system

Answer 26

1. the pulmonary circuit takes O2 poor blood and sends it to the lungs to become oxygenated 2. once oxygenated, blood flows back to the heart then through the systemic circuit --> organs & muscles. this leads to an O2 rich and O2 poor circuit 3. there is higher blood pressure in the organs because the circuit is high pressure

Question 27

amphibians have a _____ chambered heart

Answer 27

three (2 atria and 1 ventricle)

Question 28

reptiles have a _____ chambered heart with

Answer 28

three with a more complex ventricle

Question 29

the reptile heart is more efficient than the amphibian heart because

Answer 29

there is a better separation of oxygenated and deoxygenated blood; more O2 can then be delivered to the system

Question 30

mammal and bird heart structure

Answer 30

4 chambers; left side of heart receives oxygenated blood while right side receives deoxygenated blood

Question 31

mammals and birds hearts are the most efficient because

Answer 31

oxygenated and deoxygenated blood are fully separated; there is a low and a high pressure circuit for blood flow to different areas

Question 32

process of blood flow in mammals

Answer 32

1. right ventricle pumps blood to lungs 2. in the lungs, the blood loads O2 and unloads CO2 to be exhaled 3. O2-rich blood from lungs enters heart at the left atrium, then goes to the left ventricle and is pumped through the aorta to body tissues 4. blood leaves ventricle & heart through the aorta 5. blood is sent to the peripheral capillary beds 6. at the systemic beds, blood dumps O2 then picks up CO2 and starts back to the heart 7. superior vena cava & inferior vena cava flow into the right atrium --> right ventricle

Question 33

cardiac cycle

Answer 33

the rhythmic cycle in which the heart contracts & relaxes

Question 34

relaxation or filling phase of the heart cycle

Answer 34

diastole

Question 35

contracting/pumping phase of the heart cycle

Answer 35

systole

Question 36

heart rate

Answer 36

beats/minute

Question 37

stroke volume

Answer 37

blood pumped in a single contraction or beat (ml/beat)

Question 38

cardiac output

Answer 38

volume of blood pumped into systemic circulation per minute & depends on heart rate and stroke volume (ml/minute)

Question 39

cardiac output formula

Answer 39

heart rate * stroke volume

Question 40

The 4 valves that prevent backflow of blood in the heart and their function

Answer 40

2 atrioventricular valves that separate each atrium and ventricle; 2 semilunar valves that control blood flow to the aorta & pulmonary artery

Question 41

capillaries

Answer 41

thin walls and lined with endothelium + basement membrane to facilitate exchange of materials

Question 42

arteries vs veins

Answer 42

- both have endothelium, smooth muscle, connective tissue - arteries have thicker walls than veins to accommodate high pressure of blood pumped from heart - in thinner-walled veins, blood flows back to the heart mainly as a result of muscle action

Question 43

why is the flow of blood slow in the capillaries

Answer 43

for time to diffuse/exchange materials

Question 44

systolic pressure

Answer 44

pressure in the arteries during ventricular systole; highest pressure in the arteries

Question 45

diastolic pressure

Answer 45

pressure in arteries during diastole; lower than systolic