Exam 3 ch 19, 20,22

Question 1

lacteals

Answer 1

-lymphatic capillaries in the digestive system which play a role in absorbing digested fats from the intestine and produce chyle to be carried to the blood stream

Question 2

lymphangitis

Answer 2

inflamed lymphatic vessels , congestion of related blood vessels and swollen tender areas

Question 3

lymphedema

Answer 3

-edema of the lymphatics occur because of blockage of a tumor or removed part of lymphatics(cancer)

Question 4

buboes

Answer 4

• swollen lymph nodes that are full of large # of infected bacteria, symptom of Bubonic plague

Question 5

tonsillar crypts

Answer 5

-in tonsils:invaginations of overlying epithelium to trap bacteria and particulate matter which then work their way into lymphoid tissue and most destroyed

Question 6

elephantiasis

Answer 6

where your lymphatics in lower limbs accumulate with parasitic worms

Question 7

Hodgkin’s disease

Answer 7

• malignancy of lymphoid tissue, causing swollen but non-painful lymph nodes
• fatigue, fever & sweating
• B cells are malignantly transformed into giant Reed-sternberg cells
• treated with chemo and radiation therapy

Question 8

lymphoma

Answer 8

any tumor of the lymphoid tissue

Question 9

how does lymph travel throughout the body

Answer 9

lymphatic capillaries
lymphatic collecting vessels
lymphatic trunks
lymphatic ducts

Question 10

What are 3 functions of lymph

Answer 10

1. returns extra fluid to blood stream
2. returns leaked proteins to the blood
3. carry absorbed fats from intestine to blood

Question 11

What are 2 functions of lymph nodes

Answer 11

1. Filter lymph- using macrophages to destroy microorganisms and other debris
2. help activate the immune system- strategically located sites where lymphocytes encounter antigens and are activated to mount attack against them

Question 12

T cells

Answer 12

directly attack and destroy infected cells

Question 13

b cells

Answer 13

produce plasma cells that then secrete antibodies

Question 14

lymphoid macrophages

Answer 14

• phagocytize foreign substances and help activate T cells

Question 15

spleen function

Answer 15

• largest lymphoid organ
  1) cleanse blood by extracting RBCs + has phagocytes that remove debris and foreign matter
  2) stores and releases the breakdown products of hemoglobin ex. Iron
  3) stores platelets
  4) acts as hematopoietic site in the fetus

Question 16

thymus function

Answer 16

• most active during youth
• where T cells precursors will mature
• no B cells, no follicles
• does not directly fight antigens

Question 17

tonsils

Answer 17

• the simplest lymphoid organ
• trap pathogens from food and air
• contain tonsillar crypts

Question 18

peyer’s patches

Answer 18

• aggregated patches in distal portion of sm. intestine

- destroy bacteria before it can breach the intestinal wall and generate memory cells for long term memory

Question 19

macrophage

Answer 19

• derived from monocytes (WBCs) that leave the bloodstream and enter the tissues

Question 20

phagosome

Answer 20

• forms when phagocyte adheres to a pathogen or debris , engulfs it using pseudopods

Question 21

opsonization

Answer 21

• to make tasty

- complement proteins or antibodies will coat (bind) foreign particles, makes it easier for macrophages to phagocytize

Question 22

respiratory burst

Answer 22

-helper T cells release chemicals that stimulate macrophages to release chemicals like hydrogen peroxide and bleach to kill invaders

Question 23

natural killer cells

Answer 23

-“police” blood & lymph to find cancer cells and virus-infected body cells
-they recognize the lack of self surface receptors(glycoproteins) and surface sugars of the target cells and kill target cells directly by causing apoptosis
+ secrete chemicals to enhance imflammatory response

Question 24

toll-like receptors

Answer 24

• surface membrane receptors on macrophages that recognize specific classes of attacking microbes
• trigger release of cytokines that promote inflammation and attract WBCs

Question 25

mast cells

Answer 25

release histamine

-aids in inflammatory process

Question 26

interferons IFNs

Answer 26

• help protect uninfected cells from viral infection by synthesize proteins proteins that interfere with viral replication
• reduce inflammation
• activate macrophages
• mobilize natural killer cells

Question 27

complement

Answer 27

-a group pf 20 plasma proteins that are normally inactive in the blood, but when activated release chemicals that will modify inflammation and induce bacterial cell lysis

Question 28

membrane attack complex MAC

Answer 28

• complement protein that is inserted into a cell membrane, response to C3b molecules activating it
• insertion of MAC makes a hole in the membrane, and lets water in causing the cell to lyse

Question 29

pyrogens

Answer 29

-secreted by leukocytes and macrophages, the body responds to foreign substances by increasing body temperature

Question 30

antigens

Answer 30

substances that can mobilize the adaptive immune response and provoke it
-proteins found on foreign substances

Question 31

immunogenicity

Answer 31

• the ability to stimulate proliferation to specific lymphocytes and antibodies

Question 32

reactivity

Answer 32

the ability to react with activated lymphocytes and antibodies
-complete antigens include foreign proteins, polysaccharides, lipids, pollen grains, microorganisms

Question 33

haptens

Answer 33

• incomplete antigens
• small molecules such as peptides, nucleotides and hormones are not immunogenic but are reactive
• incl. certain drugs like penicillin + chemicals in poisin ivy , animal dander

Question 34

MHC proteins

Answer 34

• self antigens
• the antigens on an individual’s own cells are strongly antigenic to other individuals
• MHC proteins are glycoproteins that mark the cell as self and are coded for by genes in the major histocompatibility complex MHC

Question 35

active immunity

Answer 35

when B cells encounter antigens and produce antibodies

Acquired 2 ways: 1. naturally acquired 2. artificially acquired

Question 36

passive immunity

Answer 36

• antibodies taken from a serum that (animal or human) is immune
• only lasts as long as antibodies do

Question 37

CD4

Answer 37

• effector CD4 cells are helper or regulatory T cells

- they can only bond to antigens linked to Class II MHC proteins on surfaces of APCs

Question 38

CD8

Answer 38

• usually become cytotoxic cells

- can bind only to antigens linked to Class I MHC proteins found on the surface of APCs

Question 39

costimulation

Answer 39

• eventhough binding to an antigen begins the process, another signal is also required to begin the process of T cell proliferation
• T cells must bind to additional surface receptors on the APC
• costimulation induces the release of cytokine chemicals, which induce the activated T cells to proliferate & differentiate