Lecture #29: Circulation In Animals I

Question 1

Why is diffusion insufficient over distances > than a few millimeters

Answer 1

because time to diffuse over a distance is the square of the distance

Question 2

_________ makes sure no substance must diffuse far to enter or leave cell.

Answer 2

The circulatory system

Question 3

What do cnidarians, who have body wall 1 or 2 cells thick,(jellyfish etc) use for digestion and diffusion?

Answer 3

Gastrovascular Cavity (has branches radiating to and from circular canal)

Question 4

Planaria and flatworms also have gatrovascular cavities that_________

Answer 4

exchange materials with environment through single opening

Question 5

What do the 2 types of circulatory systems have in common?

Answer 5

fluid (blood), tubes (blood vessels), muscular pump (heart)

Question 6

Heart powers circulation by using ________ to elevate _________ which then flows down a _______ back to the heart.

Answer 6

metabolic power
blood pressure (or hydrostatic)
pressure gradient

Question 7

Open circulatory System

_______ have OCS’s.

Organs bathed in ______ called ______ in insects

Heart pumps ________ into interconnected ______ surrounding the organs allowing exchange.

Answer 7

Insects, arthropods, and most mollusks

circulatory fluid
haemolymph(blood and intestine fluid)

Haemolymph
sinuses

Question 8

Closed Circulatory Systems

_________ have them

Blood is confined to ______ and is distinct from _______.

Hearts pump blood into ________ that branch into _______ coursing through _____.

Materials exchanged by _____ between blood and intestine fluid.

Answer 8

earthworms, squid, octopus and vertebrates

vessels
intestinal fluid

large vessels
smaller ones
organs

diffusion

Question 9

Closed system of vertebrates often called

Answer 9

cardiovascular system

Question 10

heart consists of one _____ or two ______ (chambers that receive blood returning) and one or two _____ (chambers that pump blood).

Answer 10

atrium
atria

ventricles

Question 11

3 main types of blood vessels

Answer 11

Arteries (carry blood away from heart to organs)

Veins (carry blood back)

Capillaries (form networks called capillary beds that inflate each tissue)

Question 12

arteries branch into ______, small vessels that ________

Answer 12

aterioles

convey blood to capillaries

Question 13

at downstream capillaries converge into ________ which then converge into ______ which return blood to heart.

Answer 13

venules

veins

Question 14

A ______ heart has one atrium and on ventricle

Blood pumped from ventricle to _____ where it picks up _______ and disposes of ______.

Then converges into blood vessel that _______ to _____ that surround the organs (system circulation).

Answer 14

fish

gills
oxygen
carbon dioxide

carries blood
capillary beds

Question 15

In fish blood goes through 2 ______.

When blood flows through bed ________ drops a lot.

Oxygen rich blood flows slowly, constrains _________ and limits _______

Answer 15

capillary beds

blood pressure

the delivery of oxygen to blood tissues
max aerobic metabolic rate

Question 16

What has 3 chamber heart

Answer 16

frogs and amphibians

Question 17

in 3 chamber heart, ventricle pumps blood into _______ and _______.

Answer 17

pulmo-cutaneous circulation

systemic circulation

Question 18

in pulmo-cutaneous, blood picks up ____ and releases____ before returning to heart’s _____.

System circulation takes most of _______ and supplies all ______ and returns oxygen-poor blood to _______ via veins

Answer 18

o2
co2
left atrium

returning blood
body organs
right atrium

Question 19

________ have 4 chambered heart which is divided into ________.

Answer 19

Crocs, birds, mammals

desperate right and left chambers

Question 20

in 4 chamber hearts, left side pumps/ receives only _______ and right side handles only ________

double circulation _________ so systemic circuit and prevents_________.

Answer 20

oxygen rich
oxygen poor

restores pressure
mixing oxygen rich and poor blood

Question 21

Endothermic use _______ more energy than ectotherms and there need more fuel and O2 and to remove more co2

Answer 21

ten times

Question 22

The Mammalian heart contains mostly _______

Answer 22

Cardiac muscle

Question 23

The two atria in the mammal heart have ____ walls and function___for blood returning to the heart

Answer 23

thin

collection chambers

Question 24

The ventricles have___walls and contract much more___then the atria

Answer 24

thick

strongly

Question 25

A___is one complete sequence of pumping, as the heart contracts, and filling, as it relaxes, and it’s chambers filled with blood

systole is the ______ phase
diastole is the ______ phase

Answer 25

cardiac cycle
systole
diastole

Question 26

In diastole the atria and ventricles are at___

Answer 26

rest

0.4 sec

Question 27

Atrial Systole: forsces all remaining blood out of the ____ and into the ______.

Answer 27

atria
ventricles

0.1 sec

Question 28

Ventricular Systole: blood is pumped into ______

Answer 28

large arteries

0.3 sec

Question 29

Cardiac output depends on which two factors

Answer 29

Heart rate and stroke volume which is the amount of blood pumped by the left ventricle in each contraction

Question 30

What is the average stroke volume for a human

Answer 30

75 mL

Question 31

What is the typical resting cardiac output

Answer 31

5.25 L per minute

Question 32

How many valves are in the heart and what do they do

Answer 32

There are four and they prevent backflow and keep blood moving in the correct direction

Question 33

What is an atrioventricular valve

Answer 33

Keeps blood flowing back into the atria when the ventricles contract

Question 34

What are semi lunar valve’s

Answer 34

There are two sets one between the left ventricle and one between the right ventricle and they prevent backflow from vessels into the ventricles while they’re relaxing

Question 35

What sets the rate and timing at which all cardiac muscle cells contract

Answer 35

the sinoatrial (SA) node or pacemaker

Question 36

How does the SA node Make the eight year contract in unison

Answer 36

By generating electrical impulses

Question 37

What physiological cues is the SA node influenced by

Answer 37

Two sets of nerves and hormones