Cell Adaptations- (Exam 1)

Question 1

Define atrophy

Answer 1

decrease in size and/or number of the cells and their metabolic activity after normal growth has been reached

Question 2

Define hypertrophy

Answer 2

• increased size of cells and their functions

- more common in cells with little replication

Question 3

Define hyperplasia

Answer 3

• increase in the number of cells of an organ

- cells capable of replication

Question 4

What is metaplasia?

Answer 4

• change in phenotype of a differentiated cell
• reversible if cause is removed
• most often in epithelial cells

Question 5

What is dysplasia?

Answer 5

• refers to abnormal development

- mostly of epithelial cells

Question 6

What is etiology?

Answer 6

• the study or theory of the factors that cause disease and the method of their introduction to the host
• the causes or origin of a disease or disorder

Question 7

What is acute swelling?

Answer 7

early, sub-lethal manifestation of cell damage, characterized by increased cell size and volume due to water overload

Question 8

What is the etiology of acute swelling?

Answer 8

• loss of ionic and fluid homeostasis
• failure of cell energy production
• cell membrane damage
• injury to enzymes regulating ion channels of membranes
• hypoxia, toxic agents

Question 9

Describe the gross appearance of acute cell swelling

Answer 9

• slightly swollen organ with rounded edges
• pallor compared to normal
• in cut surface: tissue bulges and cannot be easily put in correct apposition
• slightly heavy (wet organ)

Question 10

What is fatty change?

Answer 10

sub-lethal cell damage characterized by intracytoplasmic fatty vacuolation

Question 11

What are the main causes of fatty change?

Answer 11

hypoxia, toxicity, metabolic disorders

Question 12

Describe the gross appearance of fatty change

Answer 12

• diffuse yellow
• edges rounded and bulge on section
• tissue is soft, friable, greasy texture

Question 13

Irreversible injury is associated morphologically with:

Answer 13

• severe swelling of mitochondria
• extensive damage to plasma membranes, giving rise to myelin figures
• swelling of lysosomes

Question 14

Describe the gross appearance of necrosis

Answer 14

pale, soft, friable, and sharply demarcated from viable tissue by a zone of inflammation

Question 15

Describe coagulative necrosis

Answer 15

• architecture of dead tissues is preserved

- necrotic cells removed by phagocytosis or digestion by lysosomal enzymes

Question 16

Describe liquefactive necrosis

Answer 16

• architecture is liquified
• dead cells are digested and transformed into a liquid viscous mass
• occurs in tissues with high lipid content, high neutrophil recruitment, and high enzymatic release

Question 17

Describe an abscess

Answer 17

a localized collection of pus in a cavity formed by disintegration of tissues surrounded by fibrous connective tissue

Question 18

What is fibrinoid necrosis?

Answer 18

• usually seen in immune reactions involving blood vessels

- occurs when Ag-Ab complexes are deposited in walls of arteries

Question 19

What can happen when there is too little apoptosis?

Answer 19

• mutations in p53 give rise to neoplasia
• lymphocytes react against self antigens
• failure to eliminate dead cells

Question 20

What can happen when there is too much apoptosis?

Answer 20

• neurodegenerative disease
• ischemic injury
• death of virus-infected cells

Question 21

Describe Phosphatidylserine and its actions

Answer 21

• phospholipid on inner membrane
• carries a negative charge
• flips to outer membrane to signal macrophages

Question 22

What are the two types of endocytosis?

Answer 22

• potocytosis: caveolae mediated

- pinocytosis: receptor mediated

Question 23

What are 3 causes of cell injury?

Answer 23

• oxygen deficiency
• infectious agents
• immunologic dysfunction

Question 24

What are the 6 mechanisms of cell injury?

Answer 24

• depletion of ATP
• mitochondrial damage
• entry of calcium
• increased ROS
• membrane damage
• protein misfolding, DNA damage

Question 25

What is the fundamental cause of necrotic cell death?

Answer 25

depletion of ATP

Question 26

What are the 3 major consequences of mitochondrial damage?

Answer 26

- formation of the mitochondrial permeability transition pore - increased production of ROS - activation of apoptotic pathways

Question 27

What are the 3 major forms of damage resulting from accumulation of calcium?

Answer 27

- membrane damage - nuclear damage - ATP depletion

Question 28

How are ROS formed?

Answer 28

- normal metabolic processes - absorption of radiant energy - inflammation - transition metals - nitric oxide

Question 29

How are ROS removed?

Answer 29

- spontaneous decay - antioxidants - storage and transport proteins - enzymes

Question 30

What types of cells can undergo hypertrophy?

Answer 30

- cardiomyocytes - skeletal muscle cells - neurons

Question 31

What is the order of injury you will see?

Answer 31

- biochemical alterations - ultrastructural changes - light microscope changes - gross changes

Question 32

Describe the histological appearance of cellular swelling

Answer 32

- dilated cytoplasm from water uptake - enlarge cells with pale cytoplasm - increased cytoplasmic eosinophilia - nucleus in normal position

Question 33

Describe the ultrastructural changes of cellular swelling

Answer 33

- blebbing and blunting of plasma membrane, and loss of microvilli - swelling and appearance of small densities in mitochondria - dilation of ER with detachment of ribosomes - nuclear alterations such as clumping of chromatin