Passage (Fill in the Blanks)
Blood constitutes roughly (1)___ % of body weight and is composed of two main fractions: (2)___ (55%) and formed elements (45%). The liquid component contains (3)___ % water along with three key plasma proteins: (4)___ (maintains osmotic pressure), (5)___ (provides immunity), and (6)___ (essential for clotting).
Red blood cells have a lifespan of approximately (7)___ days, are formed in (8)___ , and are destroyed in the (9), which is called the "graveyard of RBCs." WBCs are classified into granulocytes [(10), eosinophils, basophils] and agranulocytes [(11)___ and monocytes]. The most abundant WBC is the (12)___ (60-65%), while the least abundant is the (13)___ (0.5-1%). Basophils secrete (14)___ (causes inflammation) and (15)___ (prevents clotting). Platelets are derived from (16)___ in the bone marrow.
In the ABO system, blood group (17)___ is the universal donor because it has no A or B (18)___ on RBCs. Blood group (19)___ is the universal recipient because it has no (20)___ in plasma. The Rh factor refers to the (21)___ antigen. If an Rh-negative mother carries an Rh-positive foetus, a condition called (22)___ may occur in subsequent pregnancies. Prevention involves injecting (23)___ within 72 hours of first delivery.
The heart's pacemaker is the (24)___ , located in the (25)___ atrium, firing at (26)___ beats per minute. The electrical impulse travels: SAN → (27)___ (which delays it 0.1 s) → (28)___ → Purkinje fibres. One cardiac cycle lasts (29)___ seconds: atrial systole (30)___ s + ventricular systole 0.3 s + (31)___ 0.4 s.
In an ECG, the (32)___ wave represents atrial depolarization; the (33)___ complex represents ventricular depolarization; and the (34)___ wave represents ventricular repolarization. Atrial repolarization is masked by the (35)___ complex.
Pulmonary arteries carry (36)___ blood; pulmonary veins carry (37)___ blood. Cardiac output = (38)___ × (39), approximately (40) litres per minute at rest.
Answer Key
- 6-8
- Plasma
- 90-92
- Albumin
- Globulins
- Fibrinogen
- 120
- Red bone marrow
- Spleen
- Neutrophils
- Lymphocytes
- Neutrophil
- Basophil
- Histamine
- Heparin
- Megakaryocytes
- O
- Antigens
- AB
- Antibodies (anti-A or anti-B)
- D
- Erythroblastosis fetalis
- Anti-D immunoglobulin (RhoGAM)
- Sinoatrial node (SAN)
- Right
- 70-75
- AVN (atrioventricular node)
- Bundle of His
- 0.8
- 0.1
- Joint diastole
- P
- QRS
- T
- QRS
- Deoxygenated
- Oxygenated
- Stroke volume (SV)
- Heart rate (HR)
- 5