MODULE 1 - BLOOD, ETC.

Question 1

What is the composition of blood

Answer 1

• plasma (55%)

* formed elements (45%)

Question 2

What is the composition of plasma

Answer 2

• water (90%)

* proteins (10%)

Question 3

Identify the formed elements of blood

Answer 3

• Red blood cells (RBCs; erythrocytes)
  
  • White blood cells (WBCs; leukocytes)
  • Platelets

Question 4

Which is the most abundant formed element

Answer 4

erythrocytes

Question 5

State the main function of each of the formed elements

Answer 5

• RBCs - transport oxygen
  
  • WBCs - immunity
  • Platelets - clotting

Question 6

Explain in general terms the production of formed elements (hematopoeisis)

Answer 6

through a sequence of divisions and differentiations stem cells produce the various formed elements in the red bone marrow

Question 7

Describe clotting process and explain why clots are red

Answer 7

Step 1: platelets clump at the site of the punctured vessel and partially seal the hole

Step 2: proteins are produced which form long threads of fibrin

Step 3: fibrin threads wind around the clump of platelets completing the seal

Trapped red blood cells give clots their red colour

Question 8

What is the myocardium

Answer 8

• middle layer of the heart

* the heart’s muscle

Question 9

Identify and distinguish between the 2 chambers of the heart

Answer 9

1. atria
   - receiving chambers - receive blood from veins
   - thinner walls
2. ventricles
   - lower set
   - pumping chambers
   - ventricular myocardium is thicker than that of the atria because of the force required to pump blood a larger distance

Question 10

Around which of those pairs is the myocardium thicker?

Answer 10

ventricles

Question 11

Which of the ventricles has the thickest wall?

Answer 11

left ventricle because it pumps blood throughout the whole body

Question 12

Trace the flow of blood and list all the vessels involved

Answer 12

Vena cava
Right atrium 
Right ventricle
Pulmonary arteries
Lungs
Pulmonary veins
Left atrium
Left ventricle
Aorta

Question 13

Identify the 3 categories of blood vessels and their function.

Answer 13

1. arteries - carry blood away from the heart
2. veins - carry blood towards the heart
3. capillaries - sites of material exchange

Question 14

Distinguish between the 3 categories of blood vessels

Answer 14

• Arteries: composed of 3 layers, middle layer is smooth muscle
• Veins: same 3 layers as arteries but with less smooth muscle
• Capillaries: simple epithelium, single layer of cells

Question 15

List the 4 major structures of the conduction system of the heart:

Answer 15

1. sinoatrial (SA) node, or pacemaker
2. atrioventricula (AV) node
3. AV bundle
4. Purkinje system

Question 16

Which structure of the heart’s conduction system initiates the signal

Answer 16

SA node or pacemaker

Question 17

Identify the 5 phases of the heart phase/cardiac cycle.

Answer 17

1. Atrial systole
2. Isovolumetric ventricular contraction
3. Ejection
4. Isovolumentric ventricular relaxation
5. Passive ventricular filling

Question 18

What is a normal resting adult heart rate?

Answer 18

60 - 80 bpm

Question 19

What is an electrocardiogram?

Answer 19

records hearts electrical activity

Question 20

Which phase of the cardiac cycle does the first heart beat appear?

Answer 20

Isovolumetric Ventricular Contraction

Question 21

What is believed to be responsible for the sound of the heartbeat?

Answer 21

2 sets of valves closing

Question 22

What does the Primary Principle of Circulation state?

Answer 22

Blood flows in response to pressure gradients

Question 23

What are the 2 factors that affect arterial blood pressure?

Answer 23

1. blood volume

2. resistance to flow/peripheral resistance

Question 24

What is the average person’s blood volume?

Answer 24

5 L

Question 25

What does stroke volume refer to?

Answer 25

how much blood (volume) is pumped per beat

Question 26

What is the average person’s blood volume?

Answer 26

5 L

Question 27

What is the function of plasma?

Answer 27

transport

Question 28

What is also known as the cardiac cycle?

Answer 28

heart beat

Question 29

What is increased urinary output indicative of?

Answer 29

high BP

Question 30

Why is blood type an important consideration in transfusion?

Answer 30

to prevent blood clumping

Question 31

Describe the vasomotor mechanism:

Answer 31

muscles in walls of arteriole may constrict (vasoconstriction) or dilate (vasodilation), thus changing diameter of arteriole

Question 32

Identify and describe 3 factors that affect venous return:

Answer 32

1. gravity
2. venus pumps
3. semilunar valves