BIOD 152: Module 5 Portage Learning Questions and Answers
2026 Practice Set
BIOD 152: Module 5 Lymphatic & Innate Immunity Test Bank
1. Which of the following is the primary function of the lymphatic system?
A. Transporting oxygen to tissues
B. Draining excess interstitial fluid and returning it to the blood
C. Producing digestive enzymes
D. Regulating blood glucose
Answer: B
Rationale: The lymphatic system maintains fluid balance by collecting filtered plasma
that leaks from capillaries and returning it to the venous circulation.
2. Once interstitial fluid enters the lymphatic capillaries, it is called:
A. Plasma
B. Serum
C. Lymph
D. Exudate
Answer: C
Rationale: Lymph is essentially the same as interstitial fluid but is specifically named
once it enters the lymphatic vessel network.
3. Lymphatic capillaries are unique because they:
A. Are closed-ended (blind-ended) tubes
B. Have thick muscular walls
C. Carry blood under high pressure
D. Lack valves
Answer: A
Rationale: Unlike blood capillaries which form a continuous loop, lymphatic capillaries
start as blunt-ended pockets in the tissues.
4. The "Thoracic Duct" drains lymph from which part of the body?
A. Only the right arm and head
B. The entire left side of the body and the lower half of the body
C. Only the lower limbs
D. The right side of the chest
,Answer: B
Rationale: The thoracic duct is the largest lymphatic vessel and empties into the left
subclavian vein, draining roughly 75% of the body's lymph.
5. Which structure prevents the backflow of lymph within lymphatic vessels?
A. High blood pressure
B. Skeletal muscle pumps
C. One-way valves
D. The heart
Answer: C
Rationale: Like veins, lymphatic vessels are low-pressure systems that rely on
numerous valves to keep fluid moving toward the heart.
6. "Lymphedema" is a condition characterized by:
A. An overactive immune system
B. Swelling due to a blockage in lymphatic drainage
C. Low white blood cell count
D. High blood pressure
Answer: B
Rationale: If lymph nodes are removed or vessels are damaged, fluid accumulates in
the interstitial spaces, causing chronic swelling.
7. Which of the following are considered "Primary Lymphatic Organs"?
A. Spleen and Lymph Nodes
B. Tonsils and Peyer's Patches
C. Red Bone Marrow and Thymus
D. Appendix and Spleen
Answer: C
Rationale: Primary organs are where lymphocytes are produced (bone marrow) and
where they mature (thymus).
8. T-cells go to which organ to become "immunocompetent" (mature)?
A. Thyroid
B. Thymus
C. Spleen
D. Liver
Answer: B
Rationale: T-lymphocytes migrate from the bone marrow to the thymus to undergo a
rigorous selection process before entering circulation.
, 9. What happens to the "Thymus" as a person ages?
A. It gets larger and more active
B. It remains the same size throughout life
C. It atrophies and is replaced by fat and connective tissue
D. It moves into the abdominal cavity
Answer: C
Rationale: The thymus is most active during childhood; after puberty, its function
declines significantly.
10. Which lymphatic organ filters the "Blood" rather than the lymph?
A. Lymph node
B. Tonsil
C. Spleen
D. Peyer’s Patch
Answer: C
Rationale: The spleen is the largest lymphatic organ; it filters pathogens from the blood
and recycles old red blood cells.
11. "White Pulp" in the spleen is primarily involved in:
A. Storing platelets
B. Breaking down old hemoglobin
C. Immune functions (lymphocyte activation)
D. Producing bile
Answer: C
Rationale: White pulp contains clusters of lymphocytes that monitor the blood for foreign
antigens.
12. "Red Pulp" in the spleen is responsible for:
A. Filtering lymph
B. Disposing of worn-out RBCs and blood-borne pathogens
C. Maturing T-cells
D. Secreting hormones
Answer: B
Rationale: Red pulp consists of blood-filled venous sinuses where macrophages clean
the blood.
13. Small, bean-shaped organs that filter lymph along the lymphatic vessels are
called:
A. Adenoids
B. Lymph nodes
2026 Practice Set
BIOD 152: Module 5 Lymphatic & Innate Immunity Test Bank
1. Which of the following is the primary function of the lymphatic system?
A. Transporting oxygen to tissues
B. Draining excess interstitial fluid and returning it to the blood
C. Producing digestive enzymes
D. Regulating blood glucose
Answer: B
Rationale: The lymphatic system maintains fluid balance by collecting filtered plasma
that leaks from capillaries and returning it to the venous circulation.
2. Once interstitial fluid enters the lymphatic capillaries, it is called:
A. Plasma
B. Serum
C. Lymph
D. Exudate
Answer: C
Rationale: Lymph is essentially the same as interstitial fluid but is specifically named
once it enters the lymphatic vessel network.
3. Lymphatic capillaries are unique because they:
A. Are closed-ended (blind-ended) tubes
B. Have thick muscular walls
C. Carry blood under high pressure
D. Lack valves
Answer: A
Rationale: Unlike blood capillaries which form a continuous loop, lymphatic capillaries
start as blunt-ended pockets in the tissues.
4. The "Thoracic Duct" drains lymph from which part of the body?
A. Only the right arm and head
B. The entire left side of the body and the lower half of the body
C. Only the lower limbs
D. The right side of the chest
,Answer: B
Rationale: The thoracic duct is the largest lymphatic vessel and empties into the left
subclavian vein, draining roughly 75% of the body's lymph.
5. Which structure prevents the backflow of lymph within lymphatic vessels?
A. High blood pressure
B. Skeletal muscle pumps
C. One-way valves
D. The heart
Answer: C
Rationale: Like veins, lymphatic vessels are low-pressure systems that rely on
numerous valves to keep fluid moving toward the heart.
6. "Lymphedema" is a condition characterized by:
A. An overactive immune system
B. Swelling due to a blockage in lymphatic drainage
C. Low white blood cell count
D. High blood pressure
Answer: B
Rationale: If lymph nodes are removed or vessels are damaged, fluid accumulates in
the interstitial spaces, causing chronic swelling.
7. Which of the following are considered "Primary Lymphatic Organs"?
A. Spleen and Lymph Nodes
B. Tonsils and Peyer's Patches
C. Red Bone Marrow and Thymus
D. Appendix and Spleen
Answer: C
Rationale: Primary organs are where lymphocytes are produced (bone marrow) and
where they mature (thymus).
8. T-cells go to which organ to become "immunocompetent" (mature)?
A. Thyroid
B. Thymus
C. Spleen
D. Liver
Answer: B
Rationale: T-lymphocytes migrate from the bone marrow to the thymus to undergo a
rigorous selection process before entering circulation.
, 9. What happens to the "Thymus" as a person ages?
A. It gets larger and more active
B. It remains the same size throughout life
C. It atrophies and is replaced by fat and connective tissue
D. It moves into the abdominal cavity
Answer: C
Rationale: The thymus is most active during childhood; after puberty, its function
declines significantly.
10. Which lymphatic organ filters the "Blood" rather than the lymph?
A. Lymph node
B. Tonsil
C. Spleen
D. Peyer’s Patch
Answer: C
Rationale: The spleen is the largest lymphatic organ; it filters pathogens from the blood
and recycles old red blood cells.
11. "White Pulp" in the spleen is primarily involved in:
A. Storing platelets
B. Breaking down old hemoglobin
C. Immune functions (lymphocyte activation)
D. Producing bile
Answer: C
Rationale: White pulp contains clusters of lymphocytes that monitor the blood for foreign
antigens.
12. "Red Pulp" in the spleen is responsible for:
A. Filtering lymph
B. Disposing of worn-out RBCs and blood-borne pathogens
C. Maturing T-cells
D. Secreting hormones
Answer: B
Rationale: Red pulp consists of blood-filled venous sinuses where macrophages clean
the blood.
13. Small, bean-shaped organs that filter lymph along the lymphatic vessels are
called:
A. Adenoids
B. Lymph nodes
