Ch 21 Lymphatic System Part 2

Question 1

T lymphocytes

Answer 1

Mature in thymus

Question 2

B lymphocytes

Answer 2

Activation causes proliferation and differentiation into plasma cells that produce antibodies

Question 3

Macrophages

Answer 3

• develop from monocytes
• phagocytize tissue debris, dead neutrophils, bacteria, and other foreign matter
• have antigen presenting cells

Question 4

Dendritic cells

Answer 4

• branched, mobile APCs found in epidermis, mucous membranes, and lymphatic organs
• alert immune system to pathogens that have breached their surface

Question 5

Natural killer cells

Answer 5

Large lymphocytes that attack and destroy bacteria, transplanted tissue, host cells infected with viruses or have turned cancerous

Question 6

Metastasis

Answer 6

Phenomenon in which cancerous cells break free from the primary tumor, travel to other sites in the body and establish new tumors

Question 7

Treatments of breast cancer

Answer 7

Lumpectomy, mastectomy, and removal of nearby axillary lymph nodes

Question 8

Three lines of defense against pathogens

Answer 8

1. External barriers
2. Nonspecific defense mechanisms
3. Immune system

Question 9

External barriers

Answer 9

• skin: hard for microorganisms to enter body; includes keratin, peptides, and sweat that kill or prohibit growth of bacteria
• mucous membranes: protects organs, traps microbes, and has lysozymes that destroy bacterial cell walls

Question 10

Fever

Answer 10

• abnormal elevation of body temp, an adaptive defense mechanism
• promotes interferon activity
• inhibits reproduction of bacteria and viruses

Question 11

Exogenous pyrogens

Answer 11

• initiation of fever
• glycolipids on pathogen surfaces
• stimulate neurons in anterior hypothalamus to secrete Prostaglandin E2

Question 12

PGE2

Answer 12

Raises hypothalamic set point for body temp

Question 13

Antipyretics

Answer 13

Fever-reducing medications act by inhibiting the production/release of PGE2

Question 14

Inflammation

Answer 14

Local defensive response to tissue injury

• limit spread of pathogens, then destroy them
• remove debris from damaged tissue
• initiate tissue repair

Question 15

4 Cardinal signs of inflammation

Answer 15

Redness, swelling, pain, and heat

Question 16

Cytokines

Answer 16

Class of chemicals that regulate inflammation and immunity

• secreted mainly by leukocytes
• alter physiology or behavior of receiving cell
• act at short range

Question 17

Local hyperemia

Answer 17

Increasing blood flow beyond normal

- washed toxins and metabolic waste from the site more rapidly

Question 18

Selectins

Answer 18

Cell-adhesion molecules that aid in the recruitment of leukocytes (make membranes sticky)

Question 19

Diapedisis or emigration

Answer 19

Leukocytes crawl through gaps in the endothelial cells and enter tissue fluid

Question 20

Basis of heat of inflammation

Answer 20

Results from hyperemia

Question 21

Basis of redness of inflammation

Answer 21

Due to hyperemia, and RBCs in tissue

Question 22

Basis of swelling of inflammation

Answer 22

Due to increased fluid filtration from capillaries

Question 23

Basis of pain of inflammation

Answer 23

Nerve injury, pressure on nerves from edema, stimulation of pain receptors by prostaglandins, bacterial toxins, and a bradykinin

Question 24

Fibrinogen

Answer 24

Filters into tissue fluid clots

- forms a sticky mesh that walls off microbes

Question 25

Heparin

Answer 25

- prevents clotting at site of injury - pathogens are in a fluid pocket surround by clot - attacked by antibodies, phagocytes, and other defenses

Question 26

Chemotaxis

Answer 26

Attraction to chemicals (bradykinin and leukotrienes) that guide them to the injury site

Question 27

Monocytes

Answer 27

- primary agents of tissue cleanup/repair | - arrive in 8-12 hours, convert into macrophages which consume bacteria, damaged cells, and dead and dying neutrophils

Question 28

Edema

Answer 28

- forces open valves of lymphatic capillaries promoting lymphatic drainage from swelling - lymphatic vessels collect and remove bacteria, dead cells, proteins, and tissue debris better than blood capillaries

Question 29

Pus

Answer 29

Accumulation of dead neutrophils, bacteria, other cellular debris, and tissue fluid form a pool of yellowish fluid