Circulatory Unit

Question 1

Right atrium

Answer 1

The right atrium filled with blood returning from the body

Question 2

Left atrium

Answer 2

The left atrium fills with blood returning from the lungs

Question 3

Left ventricle

Answer 3

The left ventricle receives blood from the left atrium and pumps blood to the body

Question 4

Right ventricle

Answer 4

The right ventricle receives blood from the right atrium and pumps blood to the lungs

Question 5

Atrioventricular valve

Answer 5

Atrioventricular valve is a valve in the heart between the ventricle and atrium

Question 6

Tricuspid valve

Answer 6

It is the av valve on the right side of the heart. It has three flaps

Question 7

Bicuspid valve

Answer 7

It is the av valve on the left side of the heart. Also called the mitral valve. It has two flaps

Question 8

Semi lunar valves

Answer 8

Semi lunar valves are hard-mooned shaped and are valves between the ventricles and the large arteries; it carries blood away from the heart

Question 9

Aorta

Answer 9

Is an artery that carries blood directly from the heart to other arteries

Question 10

Pulmonary vein

Answer 10

Pulmonary vein is a blood vessel that carries blood from the lungs to the heart

Question 11

Superior vena cava

Answer 11

The superior vena cava collects oxygen-poor blood coming from the tissues in the head, chest, and arms

Question 12

Inferior vena cava

Answer 12

The inferior vena cava collects oxygen-poor blood coming from the tissues elsewhere in the body

Question 13

Coronary artery

Answer 13

A coronary artery is an artery that supplies blood to the heart muscle

Question 14

Auricles

Answer 14

Auricles are two pouches that are connected to the heart’s atrium. They transfer blood into the ventricles.

Question 15

Papillary muscles

Answer 15

Papillary muscles are muscle located in the ventricles of the heart

Question 16

Chordae tendenae

Answer 16

Chordae tendenae, or heart strings, are cord-like tendons that connect the papillary muscles to the av valves

Question 17

Myocardium

Answer 17

Myocardium is the thick, middle layer of the heart and is composed of cardiac muscle

Question 18

Endocardium

Answer 18

Endocardium is the thin, smooth membrane that lines the inside of the chambers of the heart and forms the surface and of the valves

Question 19

Pericardium

Answer 19

Pericardium is the membrane enclosing the heart, consisting of an outer fibrous layer and an inner double layer of serous membrane

Question 20

Pulmonary circulation

Answer 20

• Begins at the right ventricle and ends at the left atrium
• Carries blood between the heart and lungs
• Adds oxygen and removes carbon dioxide from the blood

Question 21

Systemic circulation

Answer 21

• Starts at the left ventricle and ends at the right atrium
• Arteries of systemic circulation reach all the body cells and tissues
• Arteries eventually branch to form smaller and smaller vessels that terminate in capillaries. Capillaries are the site of the exchange of materials between the blood and the body cells.
• As the blood returns to the heart from the body, they will flow first through the capillaries that merge to become veins

Question 22

Three major types of systemic loops of circulation:

Answer 22

Coronary circulation: supplies blood to muscles of the heart
Hepatic portal circulation: carries blood from the digestive tract to the liver
Renal circulation: carries blood to and from the kidneys

Question 23

Veins

Answer 23

Veins transport blood at a lower pressure and are not as strong as arteries. Veins have the same three layers as arteries but are much thinner. Veins carry deoxygenated blood back to the heart. They prevent blood flowing backwards by having one way valves.

Question 24

Arteries

Answer 24

The smooth elastic muscles of the artery helps the heart pump the blood. When the heart beats, the artery will expand as it fills with blood. When the heart replaces, the artery will contract, exerting a force that is strong enough to push the blood along. This rhythm between the heart and the artery results in an efficient circulatory system.

Question 25

Capillaries

Answer 25

Capillaries are spread throughout body like fine network. Capillary wall is a single layer of one epithelial cell thick.

Question 26

Describe the three layers of an artery/ vein

Answer 26

a. An outer layer of connective tissue b. A middle layer of smooth muscle which is very elastic and strong. c. An endothelium made up of very smooth epithelial cells. These smooth cells allow blood to flow smoothly through an artery.

Question 27

How are capillaries involved in the body's release of excess heat?

Answer 27

To release heat, the blood delivers the heat to the capillaries which then rapidly release the heat into the tissues. The result is that your skin takes on a flushed appearance.

Question 28

SA node

Answer 28

The Sinoatrial node, also called the pacemaker of the heart. Is a bundle of specialized muscle tissue. It is within the myocardium of the right atrium, near top of heart. The SA node stimulates the myocardial cells in the atria to contract and relax rhythmically.

Question 29

The heart beat cycle

Answer 29

The SA node sends an electrical signal that spreads across the walls of the two atria making them contract simultaneously. As they contract the signal continues to the AV node (atrioventricular node). The AV node transmit the signal through a fibres called the bundle of His. The bundle of His branches into two bundle branches which split off into Purkinje fibres. Purkinje fibres are responsible for initiating the contract of muscle cells in the right and left ventricles

Question 30

Diastole:

Answer 30

Period of relaxation of the ventricles - AV valves (bicuspid and tricuspid) are open - Blood flows from the atria to the ventricles - Bt the end of diastole the ventricles are 70% fill * Diastole pressure is the lowest pressure before the ventricles contract

Question 31

Systole:

Answer 31

Period of contract of the ventricles - The atria contract forcing more blood into the ventricles (filling them) - The ventricles contract - The pressure against the AV valve forces them shut and opens the semi lunar valves - Blood flows into the pulmonary artery and aorta * Systolic pressure is the max pressure during ventricular contraction

Question 32

The "lub" sound is produced by the:

Answer 32

The "lub" sound is produced by the closing of the AV valves (tricuspid and bicuspid)

Question 33

The "dub" sound is made by:

Answer 33

The "dub" sound is made by the closing of the semi lunar valves.

Question 34

Blood pressure is regulated in two ways:

Answer 34

Sensory neurons and kidneys

Question 35

Sensory neurons:

Answer 35

Sensory neutrons attached to blood vessels which are connected to the autonomic nervous system (the part of the nervous system that controls involuntary activities)

Question 36

Kidneys:

Answer 36

When a person's blood pressure becomes too high, the kidneys move more water from the blood, decreases the total amount of fluid in the circulatory system which in turn lowers the blood pressure.

Question 37

Low blood pressure:

Answer 37

slows down the rate at which blood flows through the body. As a result, parts of the body that are far away from the heart don't receive enough blood which can result in chilling or injury to these parts.

Question 38

High blood pressure:

Answer 38

excessively high blood pressure. The heart of a person having this condition has to work much harder to pump blood in which causes the heart muscle to weaken and may lead to leaks in the arteries. Causes of hypertension include: obesity, lack of exercise, smoking, heredity

Question 39

What measures arterial pressure?

Answer 39

A sphygmomanometer.

Question 40

What is blood pressure stated in?

Answer 40

Systolic pressure over diastolic pressure.

Question 41

What is the normal blood pressure in a resting adult?

Answer 41

120/80

Question 42

When is blood pressure usually measured in?

Answer 42

The brachial artery of the upper arm where the pressure is greatest.

Question 43

What are blood's three main functions?

Answer 43

Transportation of: -nutrients, dissolved gases (O2 and CO2), hormones, waste products (from cell activity) Regulation of: -body temperature (release heat in capillaries) -pH (detection in carotid and aortic bodies) -Electrolyte balance (ions in a solution that conduct electricity important in cell function) -waste levels/ fluid balance Protection: -protects body from disease causing organisms by carrying a variety of "protector" white blood cells -clots cut to prevent infection and blood loss

Question 44

The human body contains how much blood?

Answer 44

The human body contains about 4 to 6 L of blood (about 8% of the total mass of the body). Approximately 45% of the blood consists of living cells. The remaining 55% is fluid called plasma.

Question 45

Blood plasma

Answer 45

Blood plasma is a clear, straw-coloured fluid that is 90% water and 10% dissolved substances including: fatty acids, salts, glucose, protein, amino acids, vitamins, enzymes, hormones and wastes

Question 46

What are the three types of plasma proteins?

Answer 46

Albumins, globulins, and fibrinogen

Question 47

Albumin

Answer 47

The most abundant of the plasma proteins; keeps water from leaving the blood and entering the surrounding cells by osmosis

Question 48

Globulin

Answer 48

Some are involved in transporting proteins and other materials from one part of the body to another; others, called antibodies, are proteins that bind to and help destroy foreign substances in the body

Question 49

Fibrinogen:

Answer 49

Is involved in the clotting of the blood.

Question 50

What are red blood cells also called?

Answer 50

Erythrocytes

Question 51

The most numerous of the blood cells and how many?

Answer 51

Red blood cells are the most numerous; about 30 trillion in an adult

Question 52

What is hemoglobin?

Answer 52

Hemoglobin is an iron-containing protein that carries oxygen from the lungs to body tissues and gives red blood cells their colour.

Question 53

A mature blood cell

Answer 53

Have gradually been filled with hemoglobin. Hemoglobin forces out a RBC's nuclei and organelles therefore a mature RBC has no nucleus.

Question 54

Life span of red blood cell

Answer 54

Human RBCs are made by bone marrow and have an average life span of 120 days. New RBCs are formed at the same rate that old RBCs are destroyed - about 2 million every second

Question 55

Red blood cells

Answer 55

Are shaped like biconcave disks, are red in colour, and carry O2 and CO2

Question 56

Worn out RBCs

Answer 56

Worn out RBCs are destroyed by special with blood cells in the liver and the spleen. The iron in the hemoglobin is held by the body and reused.

Question 57

What are white blood cells also called?

Answer 57

Leukocytes

Question 58

Number of RBC to WBC

Answer 58

500 to 1. However! WBC levels will increase when required

Question 59

Main function of white blood cells

Answer 59

To protect the body against invasion by foreign cells (such as viruses or bacteria) or substances

Question 60

White blood cells:

Answer 60

- produced in bone marrow - larger than RBCs - almost colourless - contain no hemoglobin - have a nucleus - live for many months or years

Question 61

The 5 main types of white blood cells

Answer 61

``` Lymphocytes Monocytes Eosinophils Basophils Neutrophils ```

Question 62

Platelets

Answer 62

Platelets are cell fragments involved in blood clotting. They are formed by the pinching off of bits of cytoplasm from large cells within the bone marrow. The blood of an adult has about 1.5 trillion platelets.

Question 63

Clotting:

Answer 63

the solidification of blood at the site of an injured blood vessel

Question 64

When a blood vessel is injured:

Answer 64

When a blood vessel is injured, the platelets in the blood stick to the wall of the damaged vessel and rupture. If the damage to the vessel is minor, material from the ruptured platelets seal the leak. If the break is more serious, then the clotting process is triggered.

Question 65

The process of blood clotting

Answer 65

1. The ruptured platelets and the wall of the injured blood vessel release an enzyme, called thromboplastics 2. Thromboplastin initiates a series of enzymatic reactions. The result of these reactions is the conversion of prothrombin, a plasma protein, into thrombin. 3. Thrombin converts soluble fibrinogen (found in plasma) into insoluble strands of fibrin. 4. Fibrin forms a network of stands that trap red blood cells and platelets to form a clot. Kind of like a wire net that taps red blood cells and platelets.

Question 66

The clot:

Answer 66

The clot stops the bleeding, contracts, and hardens. In time, the wound is repaired by the growth of cells that replace the cells damaged by the injury. When healing is completed, a plasma enzyme is activated and dissolves the fibrin clot.

Question 67

How have humans tried to think of ways to transfer blood into injured victims?

Answer 67

They began by trying to transfer blood from animals such as cows but this resulted in illness and death. Then they tried to transfer small amounts of blood from one human to another. When they did this some of the patients would die and others would live.

Question 68

Antigens:

Answer 68

Antigens are proteins that stick out of the surface of our red blood cells. Two types: A&B

Question 69

Blood antibodies:

Answer 69

Are produced in response to "foreign antigens". If a foreign antigen enters the blood (say via an incorrect blood transfusion) antibodies will be produced and will circulate in the blood and bind to the foreign antigens. This clumps the RBCs together in a process called agglutination. If the immune system doesn't work quickly enough, agglutination of the foreign blood can create blood clots that can clog arteries in the body causing a stroke or heart attack.

Question 70

Universal Donor:

Answer 70

The blood type that can donate to all groups is blood type "O"

Question 71

Universal Receiver:

Answer 71

The blood type that can receive from all groups "AB"

Question 72

Symbol for A antigen

Answer 72

circles

Question 73

Symbol for B antigen

Answer 73

triangles

Question 74

Rh factor stands for

Answer 74

The rhesus factor

Question 75

The Rh factor

Answer 75

The Rh factor is an antigen present in the RBCs of about 85-90% of the human population. This antigen was discovered in rhesus monkey.

Question 76

Why is a mother that is Rh- in risk with an Rh+ fetus?

Answer 76

The Rh- mother will make antibodies against Rh+ factor. If the antibodies against the baby's blood are introduced and agglutination or clumping of the fetus's blood may result in a hemolytic disease of the newborn. Doctors can treat this by injecting the mother with a competitive inhibitor that will inactive the fetal antigens that enter her body.