Medical Terminology

Step 1: Understanding cardiac output.
Cardiac output (CO) is the volume of blood pumped by each ventricle per minute.
It is calculated as:
Step 2: Normal values.
- Stroke volume in an average adult = 70 ml/beat.
- Heart rate in an average adult = 72 beats/min.
Thus,
Step 3: Clinical importance.
Cardiac output ensures adequate delivery of oxygen and nutrients to tissues.
Any significant deviation (too low or too high) may indicate heart failure, shock, or compensatory mechanisms.
Step 4: Analysis of options.
- (A) 5300 ml/min: Slightly higher, not the typical reference.
- (B) 5250 ml/min: Close but not standard.
- (C) 5200 ml/min: Correct, widely accepted average value.
- (D) 5350 ml/min: Too high compared to normal resting values.
Step 5: Conclusion.
The average cardiac output of an adult is about 5200 ml/min.

Step 1: Recall function of AV valves.
Atrioventricular (AV) valves (tricuspid and mitral) regulate blood flow between atria and ventricles, preventing backflow.
Step 2: Sequence of operation.
1. Blood returning to atria increases pressure, forcing AV valves open (D).
2. Once open, valve flaps hang limply into ventricles (E).
3. Atria contract, pushing more blood into ventricles (A).
4. Ventricles then contract, pushing blood against AV valve flaps (C).
5. Chordae tendinae tighten to keep valve flaps closed and prevent backflow (B).
Step 3: Analysis of options.
The correct sequence is D E A C B.
Step 4: Importance.
This sequence ensures unidirectional blood flow — atria to ventricles, then ventricles to arteries, without regurgitation.

Step 1: Background on Drosophila eye colour.
In genetics, Drosophila melanogaster (fruit fly) is widely studied for inheritance patterns.
The wild-type allele (W ) is the normal allele found in natural populations.
Step 2: Phenotype of W allele.}
The W allele produces red eye colour, which is considered the normal or standard phenotype of fruit flies.
The white-eyed mutation (w) results when the W allele is absent or defective.
Step 3: Analysis of options.
- (A) Blood: Not associated with eye phenotype.
- (B) Cherry: Not the correct genetic term used for wild-type phenotype.
- (C) Red eye: Correct, this is the classic wild-type eye colour in Drosophila.
- (D) Buff: Represents another mutation, not the wild-type.
Step 4: Conclusion.
Thus, W allele in Drosophila shows red eye phenotype.