Circulatory and Respiratory Systems

Question 1

Heart

Answer 1

Right side pumps deoxygenated blood into pulmonary circulation. Left side pumps oxygenated blood into systemic circulation

Question 2

Atria

Answer 2

Two upper chambers

Thin-walled

Question 3

Ventricules

Answer 3

Two lower chambers

Extremely muscular

Question 4

Blood flow through the heart

Answer 4

1. Through the right atrium, tricuspid valve (3 cusps) into right ventricle
2. Through pulmonary semilunar valve (3 cusps) into pulmonary arteries
3. Return through pulmonary veins into left atrium
4. Through mitral valve (2 cusps) into left ventricle
5. Through aortic semilunar valve (3 cusps) into systemic circulation

Question 5

Atrioventricular valves

Answer 5

Between the atria and ventricles

Prevent backflow into the atria

Question 6

Systole

Answer 6

Period during which the ventricles contract, forcing blood out the heart into pulmonary and systemic circulation

Question 7

Diastole

Answer 7

Period of cardiac muscle relaxation during which blood drains into all four chambers

Question 8

Cardiac output

Answer 8

The total volume of blood the left ventricle pumps out per minute
CO = HR (beats/min) X stroke volume (volume/contraction)

Question 9

Heart contraction

Answer 9

1. SA node
2. AV node
3. Bundle of His (AV bundle)
4. Purkinje fibers

Question 10

Sinoatrial node (SA)

Answer 10

Pacemaker
Small mass of specialized tissue in the wall of the right atrium
Originates cardiac contraction and spreads impulses through the atrium, stimulating the to contract simultaneously

Question 11

Atrioventricular node (AV)

Answer 11

Slowly conducts impulses to the rest of the heart allowing for atrial contraction and ventricles to fill with blood

Question 12

Bundle of His (AV bundle)

Answer 12

Branches into the right and left bundle branches down the ventricles

Question 13

Purkinje fibers

Answer 13

Up the walls of the ventricles

Stimulate strong contraction

Question 14

Types of blood vessels

Answer 14

Arteries
Veins
Capillaries

Question 15

Arteries

Answer 15

Thick-walled, muscular, elastiv vessels that transport oxygenated blood away from the heart

Question 16

Veins

Answer 16

Thin-walled, inelastic vessels that transport deoxygenated blood toward the heart
Compression depends on skeletal muscle

Question 17

Capillaries

Answer 17

Very thin walls composed of a single layer of endothelial cells across which respiratory gases, nutrients, enzymes, hormones, and wastes readily diffuse

Question 18

Lymph vessesl

Answer 18

Transport excess interstitial fluid (lymph) to the cardiovascular system, keeping fluid levels constant

Question 19

Lacteals

Answer 19

Smallest lymphatic vessels that collects fats (chylomicrons) from the villi in the small intestine and deliver them into the bloodstream

Question 20

Lymph nodes

Answer 20

Swellings along lymph vessels containing phagocytic cells (lymphocytes) that filter lymph

Question 21

Plasma

Answer 21

Liquid portion of the blood (55%)

Mixture of nutrients, salts, respiratory gases, wastes, hormones, and blood proteins

Question 22

Leukocytes

Answer 22

White blood cells
Larger erythrocytes
Serve protective funcrtions

Question 23

Platelets

Answer 23

Cell fragments that lack nuclei

Involved in clot formation

Question 24

Erythrocytes

Answer 24

Red blood cells
Biconcave, disk-like shape gives increased surface area and greater flexibility
Contains ~250 million molecules of haemoglobin, each can bind 4 oxygen

Question 25

Bone marrow

Answer 25

Site of erythrocyte formation stimulated by erythropoietin | Lose their nuclei, mitochondria, and membranous organelles to circulate for 120 days

Question 26

Antigens

Answer 26

Macromolecules that are foreign to the host organism and trigger an immune response

Question 27

Universal recipient

Answer 27

Type AB Neither anti-A nor anti-B antibodies Will not reject transfusions of any blood type

Question 28

Universal donor

Answer 28

Type O | Does not posses any surface antigens that would elicit an immune response

Question 29

Rh factor

Answer 29

Blood antigen that may be present on RBC surface Rh+ possesses Rh antigen Rh- lacks Rh antigen

Question 30

Erythroblastosis fetalis

Answer 30

Severe anemia in a fetus if the anti-Rh antibodies of the mother cross the placenta and destroy fetal red blood cells

Question 31

Clotting cascade

Answer 31

1. Platelets come into contact with exposed collagen of damaged vessel. Release chemical causing neighbouring platelets to adhere forming a platelet plug 2. Platelets release clotting factor thromboplastin 3. Thromboplastin and its cofactors Ca2+ and vitamin K convert inactive prothrombin to active thrombin 4. Thrombin converts fibrinogen into fibrin 5. Threads of fibrin coat the damaged are and trap blood cells 6. Fluid left after clotting is serum

Question 32

Ventilation

Answer 32

Process by which air is inhaled and exhaled | Take in oxygen and eliminate carbon dioxide

Question 33

Inhalation

Answer 33

Phrenic nerve innervates the diaphragm to contract and flatten External intercostal muscles contract Rib cage and chest wall push up an out Increase thoracic cavity volume, reducing pressure, causing lungs to expand and fill with air

Question 34

Exhalation

Answer 34

Diaphragm and external intercostal muscles relax Chest wall pushes inward Decrease thoracic cavity volume, increasing pressure, forcing air out and lungs deflate

Question 35

Surfactant

Answer 35

Protein complex secreted by cells in the lungs to keep lungs from collapsing by decreasing surface tension in the alveoli

Question 36

Ventilation control

Answer 36

Regulated by neurons in the medulla oblongata | Excessive CO2 and H+ in blood causes respiratory center to stimulate increased rate of ventilation

Question 37

Pulmonary capillaries

Answer 37

Dense network of minute blood vessels that surround the alveoli

Question 38

Total lung capcity

Answer 38

The maximum volume of air the lungs can hold

Question 39

Tidal volume

Answer 39

The volume of air moved during a normal resting breath

Question 40

Inspiratory reserve volume

Answer 40

The volume of air that could be additionally inhaled into the lungs at the end of a normal, resting inhalation

Question 41

Expiratory reserve volume

Answer 41

The volume of air left in the lungs at the end of a normal, resting exhalation

Question 42

Vital capacity

Answer 42

The volume of air moved during a maximum inhalation followed by a maximum exhalation

Question 43

Residual volume

Answer 43

The air left in the lungs after maximum exhalation