Circulation

Question 1

Circulation system 5 functions

Answer 1

Respiratory gas transport
Nutrient transport
Nitrogenous waste transport
Hormone transport
Heat transport

Question 2

Circ system is required in…

Answer 2

Animals larger than a certain size
Animals with more minimal oxygen demands (high metabolism)

Question 3

Circ system consists of…

Answer 3

Pumping mechanism (e.g. heart)
Plumbing (arteries and veins)
Surfaces for diffusion (capillaries)

Question 4

Two basic designs of circ system

Answer 4

Open vs. Closed circulatory systems

Question 5

Open circulatory system
Hemocoel
Interstitial space

Answer 5

Blood flows from arteries into diffuse spaces between cells (interstitial space) or into special blood cavities surrounding organs then returns to the heart via ostia
Blood in open systems is called hemolymph
Hemocoel is the body cavity of an open circulatory organism

Question 6

Closed circulatory system

Answer 6

Blood confined to vessels at all times
Materials pass into and out of blood via diffusion

Question 7

Artery vs Vein

Answer 7

Carries blood away from heart artery
Carries blood to heart vein

Veins are thinner walled,
less elastic,
have much less smooth muscle,
and are of larger diameter

Question 8

Makeup of plumbing for circ system

Answer 8

Artery -> arteriole -> capillary -> venule -> vein

Question 9

Arterioles

Answer 9

Small arteries made up primarily of smooth muscle
Circular smooth muscle can contract, reduce blood flow to particular organs
Serves as a control mechanism to divert blood to where it is most needed

Question 10

Pressure of blood when it reaches veins

Answer 10

By the time blood reaches veins, pressure has decreased to zero

Question 11

How does blood return to the heart?

Answer 11

Skeletal muscle surrounding veins applies pressure when those muscles contract
One way valves direct blood anteriorly, restrict flow posteriorly

Question 12

Differences between vertebrate circulatory patterns is related to:

Answer 12

Location of respiratory organs
Structure of Heart

Question 13

Amphibian circulatory system

Answer 13

Double circuit
Pulmonary/Systemic
Two atria, single ventricle
Both oxygen-rich and oxygen poor blood travel through the ventricle
Trabeculae prevents oxygenated and deoxygenated blood from mixing to any great extent

Question 14

Bird-mammal circulatory systems

atria/ventricle relation?
circulation?

Answer 14

Complete separation between atria and ventricles
Double Circulation - complete separation between pulmonary and systemic circuits

Question 15

Portal system
which 3?

Answer 15

Connects two capillary beds

Hepatic portal system

Renal portal system

Hypophyseal portal system (connect hypothalamus to anterior pituitary)

Question 16

Blood supplies to heart

Answer 16

Left ventricle -> aorta -> coronary arteries (left/right) -> coronary veins (left/right) -> coronary sinus -> right atrium

Question 17

CAD

death?
what builds up?
what do plaques do?
what does restricted blood flow do?
solutions?

Answer 17

Leading cause of death, killing 370,000 anually
Fat, cholesterol, and other substances collect in the artery walls
Plaques damage artery walls and block blood flow
Severe buildup of plaques lead to restricted blood flow in the muscle and then a heart attack
stent or bypass

Question 18

Hepatic portal system

what does it collect from?
where does that stuff go?
what does the stuff contain?
Where do those things go after the liver?

Answer 18

Collects venous blood from digestive tract and spleen
Delivers blood to the liver via the hepatic portal vein
portal blood contains the substances absorbed by the digestive tract
substances are processed in the liver before being either … released into hepatic veins, or store in the liver for later use

Question 19

Placenta

Answer 19

O2 and nutrients come from mother via the placental interface

Fetal wastes are passed in blood to mother via placenta

Question 20

Fetal circulation

Answer 20

Placenta -> umbilical vein -> ductus venosus -> inferior vena cava -> right atrium -> foramen ovale -> left atrium -> left ventricle -> aorta -> systemic body circulation

Question 21

Function of lungs in the fetus

Answer 21

Not functional, and some blood passes through the pulmonary trunk, which bypasses to the aorta via the ductus arteriosus

Question 22

Ductus venosus does what?

Answer 22

carries oxygenated blood and bypasses the liver, dumping oxygenated blood into the inferior vena cava

Question 23

Heartbeat
systole?
diastole?

Answer 23

contraction
Relaxation

Blood movement from atria to ventricles

Blood movement from ventricles to the body

Question 24

atrial systole/diastole
step 1 and 2

Answer 24

Step 1 : systole pushes blood from atria to ventricle
Step 2 : diastole creates negative pressure in atria and draws blood in from the venous system

Question 25

Ventricular systole/diastole step 1 and 2

Answer 25

Step 1: Diastole creates negative pressure in the ventricle and allows for blood to be drawn in Step 2: Systole of the ventricles provides force to move blood through the circulatory system

Question 26

Cardiac muscle unique quality?

Answer 26

automaticity

Question 27

Pacemaker cells location? function?

Answer 27

SA Node initiate wave of electrical activity, which stimulates contraction of cardiac muscle

Question 28

Fish circulatory system

Answer 28

Deoxygenated blood -> heart -> ventral aorta -> aortic arches (through gills) -> dorsal aorta -> rest of body

Question 29

Wave of electrical activity in heart

Answer 29

SA node -> both atria -> AV node -> AV bundles -> purkinje fibers-> both ventricles

Question 30

Heart rate control? what two nerves control heart rate? slow/fast? Where do the nerves terminate?

Answer 30

Vasomotor control center in medulla regulates HR Vagus nerve (cranial) / Accelerator nerve (spinal nerve) Vagus slows / Accelerators speed up They terminate in the SA node

Question 31

Baroreceptor 2 locations ?

Answer 31

A receptor which detects changes in blood pressure Aortic arch and carotid artery

Question 32

What influences heart rate?

Answer 32

BP, O2 and CO2 concentration, blood pH, hormones, emotional state

Question 33

BP too high? BP too low?

Answer 33

Vagus nerve slows down heart rate Accelerator nerves speeds up heart rate

Question 34

Parasympathetic vs Sympathetic

Answer 34

Para slows down, Sympa speeds up

Question 35

Chemoreceptors monitor what?

Answer 35

O2, CO2, pH of blood

Question 36

Chemoreceptors and baroreceptors communicate with what?

Answer 36

Vasomotor control center

Question 37

Capillary exchange in closed circ systems? Is it just diffusion?

Answer 37

materials (O2, nutrients, hormones) move to Capillary <--> interstitial fluid <--> body's cells and what can be sent back to systemic circulation is other materials (CO2, N wastes, hormones) No

Question 38

Blood composition of vertebrates Is plasma cellular?

Answer 38

55% plasma (acellular) (water, solutes, gases) 45% cells RBCs, WBCs, Clotting factors (erythrocytes, leukocytes, platelets/thrombocytes)

Question 39

Capillaries are permeable to? Impermeable to?

Answer 39

water, nutrients, small ions, gases large plasma proteins

Question 40

Hydrostatic pressure / Osmotic pressure relationship Do they oppose each other?

Answer 40

If hydrostatic pressure is greater than osmotic pressure, net movement favors going out of the capillary If osmotic pressure is greater than hydrostatic pressure, net movement favors going into the capillary They oppose each other

Question 41

Where is hydrostatic pressure greatest? What impact does this have?

Answer 41

At the proximal end of the capillary because blood is under higher pressure moving from a big vessel to a small vessel (protein-free) Forces water and small molecules out Important for providing tissue cells with oxygen and nutrients

Question 42

Where is colloidal osmotic pressure greatest? What impact does this have?

Answer 42

Highest at distal end of the capillary because blood is more concentrated than the interstitial fluid, drawing water and dissolved molecules (wastes) into the capillary

Question 43

Proximal end can be thought of as what?

Answer 43

Arterial (carrying nutrients in) vs Venous (carrying wastes out)

Question 44

Mechanisms for regulating blood flow

Answer 44

Contraction of smooth muscle arterioles - reduces blood flow to particular body organs Contraction of precapillary sphincters - controls flow through particular parts of a capillary bed

Question 45

Fish heart

Answer 45

Zig Zag like a S Top right of S is sinus venosus Left arch of S is atrium Bottom right arch of S is ventricle S terminates at left is conus arteriorsus

Question 46

Frog heart 6 major structures

Answer 46

Spiral valve - separates oxygen and deoxygenated blood streams (much like septum) pulmocutaneous artery - carries blood to lungs (pulmonary veins backflow to heart) Carotid artery - carries blood to head Systemic artery - carries blood to trunk trabeculae - keep O2/De-O2 blood separated pretty well

Question 47

Branchia

Answer 47

gills

Question 48

What happens when outflow exceeds inflow? Describe what causes this?

Answer 48

Excess fluid, lymph, from the interstitial space is collected by the lymphatic system More hydrostatic pressure than there is osmotic colloidal pressure forces out more than colloidal osmotic pressure brings in, causing a buildup of fluid

Question 49

Lymph returns to the circulatory system where?

Answer 49

The thoracic duct, draining into the left innominate vein of the neck

Question 50

What are major fluid compartments of an animal's body? How does blood fit into this picture?

Answer 50

Blood vessels, interstitial, and intracellular. Blood exists in the blood vessels of the body, so it would fit into the blood vessels section.

Question 51

What are the advantages of an open vs a closed circulatory system?

Answer 51

An open system would be advantageous because it would require less energy to operate since pressure does not need to be maintained as rigorously with a plumbing network, rather it would just need to organize the arterial system it has well.

Question 52

What is the main difference between the pattern of blood flow in a fish and a mammal or a bird?

Answer 52

The main difference in blood flow between a fish and a mammal/bird is the single circuit vs double circuit system. Fishes still send blood to a respiratory organ, but there is only one pump powering both, which makes it not as effective a pump as a mammal or bird. However, the fish pump requires less energy since it is only powering 1 pump rather than 2.

Question 53

Describe the pattern of blood flow through the mammalian heart, noting which chambers contain oxygenated/deoxygenated blood

Answer 53

Right atrium (de) -> Right ventricle (de) -> Pulmonary trunk (de) -> Pulmonary artery (de) -> Pulmonary veins (ox) -> Left atrium (ox) -> Left ventricle (ox) -> Aorta

Question 54

Describe the role of hemoglobin and other respiratory pigments in oxygen transport in the blood

Answer 54

Hemoglobin binds oxygen to it and transports it to cells in the body.

Question 55

How is that hemoglobin can take up oxygen in lung capillaries, but release it in tissue capillaries

Answer 55

Hemoglobin binds in low oxygen settings, so in tissues that need oxygen because not a lot is readily available, hemoglobin will release this oxygen into the plasma, the oxygen will diffuse over the blood vessel into the interstitial fluid, and enter the cell that needs it via diffusion.