w/Lab Q&A | Portage Learning
1. Blood is classified as which type of tissue?
A) Epithelial tissue
B) Connective tissue
C) Muscle tissue
D) Nervous tissue
Correct Answer: B) Connective tissue
Rationale: Blood is a specialized connective tissue with a liquid matrix (plasma)
and formed elements suspended within it. Epithelial tissue covers surfaces;
muscle contracts; nervous conducts impulses.
2. Which component of blood is primarily responsible for oxygen transport?
A) Leukocytes
B) Thrombocytes
C) Plasma
D) Erythrocytes
Correct Answer: D) Erythrocytes
Rationale: Erythrocytes contain hemoglobin, which binds and carries oxygen
from the lungs to tissues. Leukocytes fight infection; thrombocytes are for
clotting; plasma is the liquid portion.
,3. The liquid portion of blood, composed mostly of water, is:
A) Serum
B) Lymph
C) Plasma
D) Interstitial fluid
Correct Answer: C) Plasma
Rationale: Plasma is the straw‑colored fluid matrix of blood, making up about
55% of total blood volume. Serum is plasma without clotting factors; lymph is
tissue fluid.
4. Which plasma protein is most abundant and contributes significantly to
osmotic pressure?
A) Albumin
B) Globulin
C) Fibrinogen
D) Prothrombin
Correct Answer: A) Albumin
Rationale: Albumin is the most abundant plasma protein (≈4.5 g/dL). It
maintains colloid osmotic pressure, preventing fluid loss from capillaries.
Globulins are for immunity/transport; fibrinogen and prothrombin are clotting
proteins.
, 5. A deficiency of vitamin B12 leads to which type of anemia?
A) Pernicious anemia
B) Iron‑deficiency anemia
C) Aplastic anemia
D) Sickle‑cell anemia
Correct Answer: A) Pernicious anemia
Rationale: Pernicious anemia results from lack of intrinsic factor or B12,
impairing DNA synthesis in red blood cell precursors. Iron deficiency causes
microcytic anemia; aplastic is bone marrow failure; sickle‑cell is genetic.
6. The primary function of platelets is:
A) Oxygen transport
B) Hemostasis and blood clotting
C) Immune defense
D) Hormone transport
Correct Answer: B) Hemostasis and blood clotting
Rationale: Platelets (thrombocytes) adhere to damaged vessel walls, aggregate,
and release clotting factors to form a platelet plug and initiate the coagulation
cascade. They do not transport oxygen or fight infection.
7. Which white blood cell type releases histamine during allergic reactions?
A) Neutrophil