Circulatory System

Question 1

Functions of the Circulatory System

Answer 1

1. transport
2. defense
3. regulation

Question 2

Animals w/o circulatory systems

Answer 2

Question 3

Why don’t single-celled protists have a circulatory system?

Answer 3

so small, easy to simply use DIFFUSION

Question 4

What do single-celled and organisms with two cell layers use instead of a circulatory system? Why?

Answer 4

Diffusion only a short distance to diffuse to the cells of outer layer

Question 5

Why does a flat worm have a flat body?

Answer 5

maximize exposure for gas diffusion through the skin

Question 6

What is the Internal Fluid Environment in unicellular animals?

Answer 6

Cellular cytoplasm

Question 7

What is the Internal Fluid Environment in Multi-cellular animals?

Answer 7

Internal fluid

Question 8

What are the two types of Circulatory System?

Answer 8

1. Open circulatory system
2. Closed circulatory system

Question 9

What is the difference between an Open and a Closed circulatory system?

Answer 9

• Open - heart pumps directly to surrounding organs; no vessels
• Closed - blood always enclosed in vessels

Question 10

What organisms have an Open circulatory system?

Answer 10

insects, other arthropods, most mollusks

Question 11

What organisms have Closed circulatory systems?

Answer 11

earthworms, squids, octopuses, vertebrates

Question 12

What are the main parts of a Vertebrate Circulatory System?

Answer 12

1. heart 2. vessels 3. blood

Question 13

What does the heart consist of?

Answer 13

one or two atria one or two ventricles

Question 14

What is the role of the atrium?

Answer 14

receive blood from the body

Question 15

What is the role of the ventricle?

Answer 15

pump out blood from the heart

Question 16

What are the different types of vessels?

Answer 16

1. Arteries 2. Arterioles 3. Capillaries 4. Venules 5. Veins

Question 17

Arrange the different types of vessels starting from the heart.

Answer 17

heart –> arteries –> arterioles –> capillaries –> venules –> veins –> heart

Question 18

Describe the circulatory of the a fish.

Answer 18

simplest 2-chambered heart single blood circuit only has sinus venosus and conus arteriosus

Question 19

Describe the circulatory system of amphibians .

Answer 19

3-chambered heart (2 atria, 1 ventricle) double blood circuit -pulmonary and systemic circuits

Question 20

In an amphibian heart, which atria pumps deoxygenated blood from the organs?

Answer 20

RIGHT Left pumps deoxygenated blood from the skin and lungs.

Question 21

In an amphibian heart, which atria pumps deoxygenated blood from the skin and lungs?

Answer 21

LEFT Right pumps deoxygenated blood from the organs.

Question 22

Describe the circulatory system of reptiles.

Answer 22

3-chambered heart (except crocodiles) ventricle is partially divided double blood circuits -pulmonary and systemic circuits

Question 23

Describe the circulatory in mammals and birds

Answer 23

4-chambered heart double blood circuit

Question 24

What is the most efficient heart? Why?

Answer 24

MAMMALS & BIRDS There is no mixing of oxygenated and deoxygenated blood

Question 25

Outline the path of blood in the human body.

Answer 25

Blood enters the RIGHT VENTRICLE from the right atrium. RV pumps blood out of the heart to the lungs via the PULMONARY ARTERIES Blood is oxygenated in the CAPILLARIES of the LUNGS Oxygenated blood is carried back to the LEFT ARTERY by the PULMONARY VEINS Blood is pumped to the LEFT VENTRICLE from the LA Blood is pumped the the body via the AORTA CAPILLARIES of the body carry out gas exchange in organs Blood flows back to the heart (RIGHT ATRIUM) via the ANTERIOR VENA CAVA and POSTERIOR VENA CAVA.

Question 26

What is the Cardiac Cycle?

Answer 26

all activities of the heart in a single heartbeat.

Question 27

How long does the Cardiac Cycle last?

Answer 27

0.8 seconds

Question 28

Describe the activities of the cardiac cycle.

Answer 28

Atria and ventricle diastole allowing blood into the chambers. Atria systole and ventricle diastole forcing all blood into the ventricles. Atria diastole preparing for the next cycle while Ventricles systole pumping blood out of the heart and into arteries.

Question 29

Differentiate Systole and Diastole

Answer 29

Systole - contract Diastole - relax

Question 30

What is a CARDIAC OUTPUT?

Answer 30

amount of blood pumped per minute (heart rate)(stroke volume) Heart Rate - beats per second Stroke Volume - amount of blood pumped by LV in each contraction

Question 31

What is the sound made by the heart? What do they signify?

Answer 31

"lub" -recoil of blood against closed atrioventricular (AV) valves "dub" -recoil of blood against semi-lunar valves

Question 32

What is an Electrocardiogram and how does it work?

Answer 32

Detect currents from heart that is conducted through bodily fluids to the skin

Question 33

Where do the electrical impulses of the heart come from?

Answer 33

the Pacemaker cells (SA node) in the right atrium

Question 34

Outline the flow of electrical impulses in the heart

Answer 34

Pacemaker generates electrical signal Signals spread through Atria and delayed at the AV node Signals pass to heart apex Signals spread throughout the ventricles

Question 35

What two nerves affect heart rate? What do they do?

Answer 35

SYMPATHETIC -speeds up pacemaker PARASYMPATHETIC -slows down pacemaker

Question 36

Aside from the Sympathetic and Parasympathetic nerves, what also influences the pacemaker?

Answer 36

Hormones Body Temperature Exercise

Question 37

How are blood vessels structured? Outer --\> Inner

Answer 37

Tunica Adventia (connective tissue) Tunica Media (smooth muscle) Tunica Intima (endothelium)

Question 38

What prevents blood from backflow of blood?

Answer 38

Closed valves in veins

Question 39

What is the relationship between blood flow (velocity) and area?

Answer 39

Inverse relationship (increase in area = decrease in blood flow velocity)

Question 40

In which blood vessel is the blood flow velocity the slowest? What is the benefit of this?

Answer 40

CAPILLARIES Slower blood flow allows more time for gas exchange

Question 41

What is the relationship between blood pressure and blood flow?

Answer 41

Pressure is highest coming from the heart and lowest going back

Question 42

What do we use to measure blood pressure?

Answer 42

Stigmanometer

Question 43

How do we use a Stigmanometer?

Answer 43

Question 44

What are some factors affecting Blood Pressure?

Answer 44

Exercise, Nutrition, Diet, Drugs

Question 45

What are illnesses related to Blood Pressure?

Answer 45

HYPERTENSION -high blood pressure HYPOTENSION -low blood pressure

Question 46

What are precapillary sphincters?

Answer 46

Sphincters that restrict blood flow to the capillary networks by relaxing or contracting

Question 47

What is the fluid that flows out of the capillaries?

Answer 47

Interstitial fluid

Question 48

What is the make up of blood?

Answer 48

55% Plasma 45% Cellular Elements

Question 49

What is in Blood Plasma?

Answer 49

Water Ions Plasma Proteins Substances transported by blood

Question 50

What makes up the Cellular Elements in blood?

Answer 50

Erythrocytes (RBC) Leukocytes (WBC) Platelets

Question 51

Outline Blood Coagulation

Answer 51

Platelets are activated Chemicals are released to make platelets sticky forming a PLATELET PLUG Chemicals also turn PROTHROMBIN to THROMBIN THROMBIN turns FIBRINOGEN to FIBRIN Fibrin clot forms

Question 52

What is the illness witht he inability to form blood clots?

Answer 52

Hemophilia

Question 53

What are the 2 types of Hemophilia and how do they differ?

Answer 53

Hemophilia A -clotting from factor VIII deficiency Hemophilia B -clotting factor IX deficiency