Intro Health and Disease

Question 1

What is a disease

Answer 1

• Response of cells, tissues, organs, and whole organism to abnormalities in environment
• To understand, need to know environmental perturbation and how living organisms respond to
• Pathologic reaction is not pathological -> normal or physiological response to environmental perturbation

Question 2

Disease

Answer 2

• Described as end state and irreversible
• Etiology is cause or nature of environmental perturbation that leads to disease
• Greater tendency to become irreversible

Question 3

Responses to injury

Answer 3

Cellular:
- Degenerative: Reversible cell injury
- Irreversible cell injury: cell death, necrosis: series of morphological changes that ensue following cell death
- Coagulative necrosis: dead tissue appears firm, structures recognizable
- Colliquative necrosis: dead tissue appears semi-liquid, no structures recognizable
- Caseous necrosis: dead tissue resembles a soft, friable, whitish-grey clump

Proliferative/Growth response:
- Hyperplasia: increase in cell number
- Metaplasia: one type of differentiated tissue is replaced by another
- Dysplasia: alteration in size, shape, organization of mature cells
- Anaplasia: extreme form of arrested or altered differentiation
- Neoplasia: new growth, can be benign or malignant

Question 4

Hydropic degeneration

Answer 4

Injury -> Hypoxia -> ATP production decrease -> sodium and water move into cell, potassium out -> osmotic pressure increases -> more water move into cell -> cisternae of ER rupture and form vacuoles -> extensive vacuolation -> hydropic degeneration

Question 5

Liver

Answer 5

• Largest gland in body
• Located in upper right hand quadrant of abdominal cavity, inferior to diaphragm
• Subdivided into 4 lobes: right, left, quadrate, and caudate - first two comprises bulk of liver
• Liver has both endocrine and exocrine function and is major center for drug detoxification

Question 6

Liver vs Digestive System

Answer 6

• All nutrients absorbed by alimentary canal are transported to liver via portal vein; even blood from spleen routed to liver by portal system
• Nutrients delivered to liver are metabolized by hepatocytes into glycogen to be released as glucose when required

Question 7

Respiratory system

Answer 7

• Composed of lungs and sequence of airways leading to an external environment, functions in providing oxygen and eliminating CO2 from cells of body
• Subdivided into:
  - Conducting portion: situated both outside and inside lungs to convey air from external environment to lungs
  
  • Respiratory portion: located strictly within lungs, functions in actual exchange of oxygen for CO2
• Four basic properties of respiratory organ: Large vascular surface area(capillary bed), thin membrane surface(for gas exchange), method for renewing gas media within lung environment, freely circulating blood

Question 8

General anatomy of respiratory system

Answer 8

• Paired intrathorasic organs
• Divided into lobes:
  - Three on right(r. upper, r. middle, r. lower)
  - Two on left(l. upper, and l. lower)
  - Further subdivided into bronchopulmonary segments

Question 9

Responses to injury

Answer 9

• Tissue: inflammantion, arteriosclerosis, neoplasia
• Blood, thrombosis, and embolism
• Immunological(humoral and cellular)
• Systemic: endocrine, etc.

Question 10

Inflammation

Answer 10

• Reaction of vascularized tissue to local injury
• Acute inflammation: involves changes that occur within minutes of injury, and persist for several hours
• Chronic inflammation: more variable than acute, and includes several forms of tissue reactions over long period of time
• Repair: damage tissue is repaired by regeneration or replacement of damage parenchyma and storm by fibrous tissue