Muscle with two heads

Muscle with two heads

• A. Bicep
• B. Tricep
• C. Deltoid
• D. Brachialis

Answer: (A)

The idea here is about how many proximal origins a muscle has. A two-headed muscle is the one with two distinct origins. The biceps brachii fits this best: it has two heads—the long head from the supraglenoid tubercle of the scapula and the short head from the coracoid process. They join and insert on the radial tuberosity, enabling elbow flexion and forearm supination (and it can assist shoulder flexion since it crosses the shoulder joint). The other options don’t fit the two-head description: the triceps has three heads and mainly extends the elbow; the deltoid has three functional parts but isn’t described as two-headed; the brachialis has a single origin and flexes the elbow without two heads.

The idea here is about how many proximal origins a muscle has. A two-headed muscle is the one with two distinct origins. The biceps brachii fits this best: it has two heads—the long head from the supraglenoid tubercle of the scapula and the short head from the coracoid process. They join and insert on the radial tuberosity, enabling elbow flexion and forearm supination (and it can assist shoulder flexion since it crosses the shoulder joint).

The other options don’t fit the two-head description: the triceps has three heads and mainly extends the elbow; the deltoid has three functional parts but isn’t described as two-headed; the brachialis has a single origin and flexes the elbow without two heads.