Tissue Injury and Repair

Question 1

inflammation

Answer 1

• standard, initial response of body to injury
• limits the extent of injury, partially or fully eliminates the cause of injury, and initiates repair and regeneration of damaged tissue
• acute: resolves over time by healing of tissue
• if persists: becomes chronic and leads to disease conditions
• ‘-itis’: denotes inflammation of specific organ or type
  EX chronic inflammation: arthritis and tuberculosis

Question 2

necrosis

Answer 2

• accidental cell death
• causes inflammation

Question 3

apoptosis

Answer 3

• programmed cell death
• normal step-by-step process that destroys cells no longer needed by the body
• does not initiate inflammatory response

Question 4

what are the 4 cardinal signs of inflammation

Answer 4

redness, swelling, pain and local heat
—— loss of function

Question 5

vasodilation

Answer 5

• the widening of the blood vessels
• evoked by damaged cells in tissue injury
• increased blood flow leads to apparent redness and heat

Question 6

histamine

Answer 6

• potent vasodilator
• released by mast cells present in tissue degranulate
• makes endothelium lining blood vessels become leaky, which allows neutrophils, macrophages, and fluid to move from the blood into interstitial tissue spaces
• antihistamines decrease allergies by blocking histamine receptors

Question 7

edema (swelling)

Answer 7

• caused by excess liquid in tissue
• swollen tissues squeeze pain receptors and cause pain

Question 8

-prostaglandins

Answer 8

• released from injured cells
• activate pain neurons
• Non steroidal anti inflammatory drugs (NSAIDS) reduce pain and inflammation bc they inhibit synthesis of prostaglandins

Question 9

what happens after containment of injury?

Answer 9

• tissue repair phase starts w removal of toxins and waste produces

Question 10

clotting (coagulation)

Answer 10

• reduces blood loss from damaged blood vessels and forms network of fibrin proteins that trap blood cells and bind edges of wound together
• scab forms when clot dries —> reduces risk of infection
• sometimes, a mix of dead leukocytes and fluid (pus) accumulates in the wound

Question 11

angiogenesis

Answer 11

• growth of new blood vessels
• results in vascularization of new tissue (granulation tissue)
• clot pulls edges of the wound together, and it dissolves as tissue is repaired

Question 12

primary union

Answer 12

• healing of wounds where edges are close together

Question 13

secondary union

Answer 13

• as edges of the wound are pulled together by wound contraction
• stitches are recommended to promote primary union and avoid scar

Question 14

atrophy

Answer 14

• many tissues, including those in muscles, loss mass
• often as you age

Question 15

what happens to tissue as you age

Answer 15

lumps and rigitiy become widespread
- passageways, blood vessels and airways become more rigid, brain and spinal cord lose mas
- nerves don’t transmit as fast or clearly, loss of clarity and memory
- cells begin to function abnormally (leads to diseases)

Question 16

true false all cells expereience changes with aging

Answer 16

true

Question 17

telomeres

Answer 17

• regions of chromosomes necessary for cell division, shorten each time cells divide
• cells are less able to divide and regenerate

Question 18

cancer

Answer 18

• generic term for many diseases where cells escape regulatory signals
• uncontrolled growth invasion into adjacent tissues, colonizaiton of other organs
• tumors rob blood supply from the normal organs

Question 19

mutation

Answer 19

• permanent change in dna of cell

Question 20

epigenetic modifications

Answer 20

• do not affect code of dna but alter how the dna is coded
• known to generate abnormal cells

Question 21

alteration in genetic material

Answer 21

• caused by environmental agents, infectious agents, errors in replication of DNA that accumulate with age

Question 22

what would cause cell to start to divide abnormally

Answer 22

• ## if modication affects key proteins that impact cells ability to proliferate in orderly fashion

Question 23

when does a tumor become malignant or cancerous

Answer 23

• when it breaches the confines of its tissue
• promotes angiogenesis
• attracts growth of capillaries
• metastasizes to other organs

Question 24

cancer treatment

Answer 24

• surgery, radiation, chemotherapy, hormonal therapy: aim to remove or kill rapidly dividing cancer cells
• difficult and often impossible to target only cancer cells