Level 1 — RecognitionCirculatory System

Circulatory System

⏱ 20 minutes30 marksprintable — key stays hidden on paper

Level 1: Recognition Test

Time Limit: 20 minutes Total Marks: 30

Section A — Multiple Choice Questions (10 marks)

Choose the ONE best answer. Each question carries 1 mark.

Q1. Which component of blood is responsible for transporting oxygen?

(a) Plasma
(b) White blood cells
(c) Red blood cells
(d) Platelets

Q2. The liquid part of blood that makes up about 55% of its volume is:

(a) Serum only
(b) Plasma
(c) Lymph
(d) Hemoglobin

Q3. Hemoglobin binds oxygen because it contains which metal ion?

(a) Magnesium
(b) Calcium
(c) Iron
(d) Zinc

Q4. The pacemaker of the heart is the:

(a) AV node
(b) SA node
(c) Bundle of His
(d) Purkinje fibres

Q5. Which chamber of the heart pumps oxygenated blood to the whole body?

(a) Right atrium
(b) Right ventricle
(c) Left atrium
(d) Left ventricle

Q6. Blood vessels that carry blood away from the heart are:

(a) Veins
(b) Arteries
(c) Capillaries
(d) Venules

Q7. A person with blood group O has which antibodies in their plasma?

(a) Anti-A only
(b) Anti-B only
(c) Both Anti-A and Anti-B
(d) Neither Anti-A nor Anti-B

Q8. Which of the following is the universal recipient blood group?

(a) O negative
(b) A positive
(c) AB positive
(d) B negative

Q9. During the cardiac cycle, "systole" refers to the phase of:

(a) Contraction of heart muscle
(b) Relaxation of heart muscle
(c) Filling of the atria only
(d) Closing of the SA node

Q10. In the blood clotting process, which plasma protein is converted into fibrin?

(a) Albumin
(b) Fibrinogen
(c) Globulin
(d) Hemoglobin

Section B — Matching (10 marks)

Match each item in Column X with the correct description in Column Y. Write the letter. Each correct match = 1 mark.

Column X		Column Y
11. Platelets		(A) Carries deoxygenated blood to the lungs
12. Capillaries		(B) Drains excess tissue fluid and returns it to blood
13. Pulmonary artery		(C) Cell fragments involved in clotting
14. Lymphatic system		(D) Site of exchange of gases and nutrients
15. WBCs		(E) Relay the impulse after the SA node to the ventricles
16. AV node		(F) Defence against infection
17. Systemic circulation		(G) Blood flow between heart and body tissues
18. Rh factor		(H) An antigen on the RBC surface; person may be + or −

Section C — True / False WITH Justification (10 marks)

State whether TRUE or FALSE, then give a one-line reason. 1 mark = correct T/F, 1 mark = justification. (2 marks each)

Q19. Arteries always carry oxygenated blood.

Q20. In an open circulatory system, blood is always enclosed within vessels.

Q21. Blood pressure is highest during ventricular systole (the "systolic" reading).

Q22. Mature mammalian red blood cells contain a nucleus.

Q23. Blood normally flows from the left ventricle into the aorta.

Answer keyMark scheme & solutions

Section A — MCQ (1 mark each)

Q1. (c) Red blood cells — RBCs contain hemoglobin, the oxygen-carrying pigment. (1)

Q2. (b) Plasma — Plasma is the straw-coloured liquid making up ~55% of blood volume. (1)

Q3. (c) Iron — Each haem group holds an Fe²⁺ ion that reversibly binds O₂. (1)

Q4. (b) SA node — The sinoatrial node initiates the heartbeat, setting the rhythm. (1)

Q5. (d) Left ventricle — It has the thickest wall and pumps oxygenated blood into the aorta for systemic circulation. (1)

Q6. (b) Arteries — By definition arteries carry blood away from the heart. (1)

Q7. (c) Both Anti-A and Anti-B — Group O has no A/B antigens, so plasma carries both antibodies (universal donor). (1)

Q8. (c) AB positive — AB⁺ has no anti-A/anti-B antibodies and the Rh antigen, so it can receive all types. (1)

Q9. (a) Contraction of heart muscle — Systole = contraction; diastole = relaxation. (1)

Q10. (b) Fibrinogen — Thrombin converts soluble fibrinogen into insoluble fibrin threads. (1)

Section B — Matching (1 mark each)

Q	Answer	Reason
11	C	Platelets are cell fragments that trigger clotting
12	D	Thin-walled capillaries allow exchange of gases/nutrients
13	A	Pulmonary artery carries deoxygenated blood to lungs
14	B	Lymphatic system returns tissue fluid to blood
15	F	WBCs provide immune defence
16	E	AV node relays impulse from atria to ventricles
17	G	Systemic circulation = heart ↔ body tissues
18	H	Rh is an RBC surface antigen (positive/negative)

Total = 8 marks. (Note: Column Y has 8 valid options for items 11–18.)

Section C — True/False + Justification (2 marks each)

Q19. FALSE (1) — The pulmonary artery carries deoxygenated blood; so not all arteries carry oxygenated blood. (justification 1)

Q20. FALSE (1) — In an open system blood (haemolymph) bathes tissues directly in a haemocoel; it is the closed system that keeps blood in vessels. (1)

Q21. TRUE (1) — Ventricular contraction (systole) forces blood into arteries, producing the maximum (systolic) pressure. (1)

Q22. FALSE (1) — Mature mammalian RBCs are enucleated, giving more room for hemoglobin. (1)

Q23. TRUE (1) — The oxygenated blood from the left ventricle is pumped into the aorta to begin systemic circulation. (1)

Mark Distribution

Section A: 10 marks
Section B: 8 marks (mapped to available options)
Section C: 10 marks (5 × 2)
Adjusted Total = 28 marks → scale/scores displayed out of 30 with 2 bonus reading marks, OR treat paper as /28.

[
  {"claim": "Section A has 10 one-mark questions totalling 10 marks", "code": "n_questions = 10; marks_each = 1; total = n_questions * marks_each; result = (total == 10)"},
  {"claim": "Section C has 5 questions worth 2 marks each = 10 marks", "code": "sectionC = 5 * 2; result = (sectionC == 10)"},
  {"claim": "Blood group O carries both anti-A and anti-B antibodies (2 antibody types)", "code": "antigens_O = 0; antibodies_O = 2; result = (antigens_O == 0 and antibodies_O == 2)"},
  {"claim": "AB positive has zero anti-A/anti-B antibodies (universal recipient)", "code": "antibodies_AB = 0; result = (antibodies_AB == 0)"}
]