Questions And Correct Answers |
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List the functions of the lymphatic system. - Answer- Fluid balance - returns extra fluid
to the blood Immunity - fights infections (has white blood cells)
Fat absorption - absorbs fats from the digestive system
List the mechanisms by which lymph is propelled to flow through its vessels. - Answer-
Skeletal muscle contractions → squeeze lymph vessels
Breathing (respiratory pump) → pressure changes move lymph
One-way valves → prevent backflow
Smooth muscle contractions → in vessel walls
Nearby artery pulsations → help push lymph
Explain the difference between encapsulated vs. unencapsulated tissues/organs. -
Answer- Encapsulated → has a protective capsule (covering). more organized &
separated (lymph nodes) (enclosed)
Unencapsulated → no capsule. more spread out & less organized (tonsils)(uncovered)
Describe the functions of red bone marrow, lymph nodes, spleen, thymus, and tonsils
with regard to the immune system. - Answer- Red bone marrow → produces immune
cells (B & T cell origin)
Lymph nodes → filter lymph & activate immune responses
Spleen → filters blood & fights pathogens
Thymus → matures T cells
Tonsils → trap & respond to pathogens from air/food
Name the main types of immune cells that reside in the lymphatic system and state their
functions. - Answer- B cells → make antibodies
T cells → kill infected cells & control immune response
Macrophages → engulf/destroy pathogens (phagocytosis)
Dendritic cells → present antigens to activate T cells
B = antibodies | T = attack | Macro = eat | Dendritic = show
Describe lymphedema. - Answer- Happens when lymph vessels are blocked or
damaged. Fluid can't drain → accumulates in tissues (Usually affects arms or legs).
Contrast nonspecific body defenses with specific immunity. - Answer- Nonspecific
(innate) defenses → general, fast, same response every time. Example: skin,
inflammation
Specific (adaptive) immunity → targeted, slower at first, has memExample: B & T cells
, List and describe the protective characteristics of the body's external physical barriers. -
Answer- Skin → tough, blocks entry of pathogens
Mucous membranes → trap germs in sticky mucus
Cilia → sweep microbes out (respiratory tract)
Secretions (tears, saliva, sweat) → wash away & kill microbes
Stomach acid → destroys pathogens
List the inflammatory chemicals that promote inflammation. - Answer- Histamine →
widens blood vessels
Kinins → attract WBCs, increase permeability
Prostaglandins → cause pain & swelling
Complement proteins → attract WBCs, kill microbes
Cytokines → signal immune cells
List the characteristic signs/symptoms of inflammation.
• Explain what accounts for these characteristics of inflammation. - Answer- Redness →
more blood flow to the area (vasodilation)
Heat → warm blood from increased circulation
Swelling → fluid leaks from vessels into tissues
Pain → chemical mediators (like prostaglandins) irritate nerves
Loss of function → swelling & pain limit movement
List in order and describe the steps of inflammation. - Answer- Tissue injury → cells are
damaged
Release of chemicals → histamine, kinins, prostaglandins signal danger
Vasodilation & increased permeability → blood vessels widen, leak fluid → redness,
heat, swelling
Phagocyte mobilization → WBCs move to the site & engulf pathogens
Tissue repair → healing begins
Identify the leukocytes that are considered cellular barriers of the body's nonspecific
defense. - Answer- Neutrophils → engulf bacteria
Eosinophils → attack parasites
Basophils → release histamine
Macrophages → phagocytize pathogens & debris
List the steps of phagocytosis. - Answer- Chemotaxis → phagocyte moves toward
pathogen
Adherence → phagocyte attaches to pathogen
Ingestion → pathogen is engulfed into a vesicle (phagosome)
Digestion → lysosomes break down the pathogen
Exocytosis → waste is expelled
Explain the cause of a fever and its advantages/disadvantages. - Answer- Cause:
Chemicals called pyrogens (from bacteria or WBCs) reset the hypothalamus to raise
body temperature.