Coracoid process is on:

Correct Answer: B

Rationale: The coracoid process, a hook-like projection on the scapula, extends anteriorly below the clavicle, anchoring muscles like pectoralis minor and biceps. It stabilizes the shoulder joint. The humerus, articulating with the scapula, lacks this process. The femur, in the thigh, supports leg movement, not shoulder. The pelvic girdle (ilium, ischium, pubis) forms the hip, unrelated to upper limb anatomy. The scapula's coracoid is distinct, critical for shoulder mechanics, unlike arm, leg, or pelvic structures, reflecting its upper body role.

Correct Answer: D

Rationale: Abductor names a muscle moving the leg away from the midline, like gluteus medius abducting the thigh. Flexor (e.g., biceps femoris) bends joints, decreasing angles. Adductor (e.g., adductor longus) pulls the leg inward. Extensor (e.g., quadriceps) straightens joints, not moving laterally. Abduction's outward action aligns with the term, distinguishing it from bending, inward, or straightening motions, key for leg positioning.

Correct Answer: A

Rationale: Axial (e.g., serratus anterior) and scapular (e.g., trapezius, rhomboids) muscles stabilize the pectoral girdle (scapula, clavicle). Axial alone omits scapular roles. Appendicular includes limb movers, not all stabilizers. Combining both captures serratus anchoring scapula to ribs and trapezius/rhomboids positioning it, distinguishing them, vital for shoulder stability.

Correct Answer: A

Rationale: Gram-negative bacteria possess a unique cell wall with an outer membrane containing lipopolysaccharides (LPS). These LPS molecules, termed endotoxins, are integral structural components released upon cell damage or death, triggering strong immune responses like fever or septic shock. Exotoxins are secreted proteins, not wall components, and 'toxins' is too vague. 'None of the above' ignores LPS's role. Endotoxins' presence in the gram-negative wall, distinct from gram-positive peptidoglycan, and their release mechanism underline their identity as key immunological triggers, differentiating them from secreted toxins.

Correct Answer: D

Rationale: Boiling points depend on intermolecular forces. Glycerol, with three hydroxyl groups, forms extensive hydrogen bonds, requiring more energy to vaporize, yielding a boiling point of 290°C. Water (100°C) has strong hydrogen bonding but fewer sites per molecule. Ethanol (78°C) has one hydroxyl, and ether (34.6°C) relies on weaker dipole forces. Glycerol's multiple bonding sites create stronger attractions, elevating its boiling point, a key factor in its use in high-temperature applications, distinguishing it from less bonded compounds.