Chapter 18-23

Question 1

What causes the normal heart sounds?

Answer 1

Two sounds (lub-dup) associated with the closing of heart valves

Question 2

Why is the left ventricle thicker than right?

Answer 2

Pumps with greater pressure than the right ventricle

Question 3

What is a heart block?

Answer 3

• Few (partial) or no (total) impulses reach ventricles
• usually caused by the AV node

Question 4

What are the characteristics of arteries?

Answer 4

smaller lumen, no valves, thicker walls,

Question 5

What do capillaries do ?

Answer 5

capillaries are very thin-walled blood vessels that exchange oxygen and other materials across the vessel wall.

Question 6

What are the effects of exercise on blood flow?

Answer 6

• Coronary vessels dilate in response to local accumulation of vasodilators
• Blood flow may increase three to four times

Question 7

When the thymus is most active?

Answer 7

The thymus is most active during youth

Question 8

The major lymphatic ducts and what they drain

Answer 8

Right lymphatic duct drains right upper arm and right side of head and thorax

Thoracic duct arises as cisterna chyli; drains rest of body

Question 9

Functions of the lymphatic system

Answer 9

Returns fluids that leaked from blood vessels back to blood

Three parts:

Network of lymphatic vessels (lymphatics)

Lymph – fluid in vessels

Lymph nodes – cleanse lymph

Question 10

Types of T cells

Answer 10

• Cytotoxic T Cells( CD8 cells)-Destroys host cells that harbour anything foreign. They are directly responsible for cell-mediated immunity
• Helper T Cells(CD4 cells)-Modulate activities of OTHER immune cells
• Regulatory T cells (TReg cells) are a special subset of T cells that prevent other immune cells from attacking the body’s own tissues and other harmless environmental materials

Question 11

Where B and T cells develop immunocompetence?

Answer 11

Thymus

Question 12

What are haptens

Answer 12

• Are small molecules not immunogenic by themselves.
• can be immunogenic if attached to body proteins and a combination is marked foreign
• poison ivy

Question 13

Types of tissue grafts

Answer 13

• Autografts: from one body site to another in the same person
• Isografts: between identical twins
• Allografts: between individuals who are not identical twins
• Xenografts: from another animal species

Question 14

What determines what our immune system can recognize and resist

Answer 14

Genes

Question 15

Characteristics of primary immune response

Answer 15

• Cell proliferation and differentiation upon first antigen exposure
• Lag period: three to six days
• Peak levels of plasma antibody are reached in 10 days
• Antibody levels then decline

Question 16

Types of immunity and how they are acquired

Answer 16

Active immunity refers to the process of exposing the body to an antigen to generate an adaptive immune response (naturally accurried, getting sick and artifical- vaccine)

Passive immunity refers to the process of providing IgG antibodies to protect against infection ( naturally accuried- mother, artifical-rabies in humans)

Question 17

What are allergies?

Answer 17

• Acute (type I) hypersensitivities

Question 18

What is the most powerful respiratory stimulus for breathing?

Answer 18

Rising CO2 levels most powerful respiratory stimulant

Question 19

What makes respiratory exchange for the fetus?

Answer 19

Gas exchange takes place via placenta

Question 20

Characteristics of tuberculosis

Answer 20

An infectious disease caused by bacterium Mycobacterium tuberculosis

Symptoms-

• fever
• night sweats
• weight loss
• a racking cough
• coughing up blood

Question 21

Characteristics Emphysema

Answer 21

Permanent enlargement of alveoli; destruction of alveolar walls; decreased lung elasticity, exhaustion from energy usage, Hyperinflation, flattened diaphragm, reduced ventilation efficiency, Damaged pulmonary capillaries, enlarged right ventricle

Question 22

Characteristics of bronchitis

Answer 22

chronic excessive mucus, Inflamed and fibrosed lower respiratory passageways, Obstructed airways, Impaired lung ventilation and gas exchange, Frequent pulmonary infections

Question 23

What increases the surface area of the small intestine?

Answer 23

• Circular folds (plicae circulares)
• Villi
• Microvilli

Question 24

Characteristics of Saliva

Answer 24

• Functions:
  
  • Cleanses mouth
  • Dissolves food chemicals for taste
  • Moistens food; compacts into bolus
  • Begins breakdown of starch with enzymes
• 97–99.5% water, slightly acidic
• Electrolytes—Na+, K+, Cl–, PO4 2–, HCO3–
• Salivary amylase and lingual lipase
• Mucin
• Metabolic wastes—urea and uric acid
• 1500 ml/day
• pH 6.75 – 7.00

Question 25

What cells secrete HCL?

Answer 25

Parietal cell

Question 26

What do bacteria in your large intestine?

Answer 26

• Colonize colon
• Synthesize B complex vitamins and vitamin K
• Metabolize some host-derived molecules (mucin, heparin, hyaluronic acid)
• Ferment indigestible carbohydrates
• Release irritating acids and gases (~500 ml/day)