A muscle that has a pattern of fascicles running along the long axis of the muscle has which of the following fascicle arrangements?

Correct Answer: C

Rationale: Parallel fascicles run along a muscle's long axis, straight from origin to insertion, as in the sartorius, optimizing range of motion over force. Circular fascicles form rings (e.g., orbicularis oculi), not linear. Pennate fibers angle into a tendon (e.g., rectus femoris), not parallel. 'Rectus' means straight but isn't a fascicle type it's a naming convention (e.g., rectus abdominis, which is parallel). Parallel arrangement's alignment with the muscle's length, enhancing lengthening/shortening, makes 'c' the correct description.

Correct Answer: B

Rationale: The vastus intermedius, part of the quadriceps, lies deep to the rectus femoris, which overlays it, both inserting into the patella via the quadriceps tendon for knee extension. Biceps femoris , a hamstring, is posterior, not overlying. Vastus medialis and lateralis , also quadriceps, are lateral and medial to intermedius, not superficial. Rectus femoris's anterior position over intermedius, per thigh anatomy, makes 'b' the correct answer.

Correct Answer: C

Rationale: The vertebral foramina of cervical vertebrae (C1-C7) are triangular, larger than in other regions, accommodating the cervical spinal cord and its mobility. Round fits thoracic/lumbar foramina more closely. Oval describes cervical bodies, not foramina. Heart-shaped is unrelated to vertebral anatomy. The triangular shape, widest at the base, reflects the cervical spine's need for space (e.g., C1's ring, C7's transition), making 'c' the correct answer per spinal anatomy.

Correct Answer: A

Rationale: Pronation turns the palm downward or posterior, with the radius rotating over the ulna, crossing at the radioulnar joints, as in typing. Supination turns it upward. Rotation is a general term, not specific here. Elevation raises, unrelated to forearm twist. Pronation's distinct radius-ulna crossover, per forearm mechanics, makes 'a' the correct answer.

Correct Answer: C

Rationale: Tight junctions form impermeable seals between adjacent cells, preventing substances from leaking between them, as in the gut lining to block bacteria. Gap junctions allow communication via channels for ions/small molecules, not sealing. Desmosomes anchor cells mechanically, resisting stress, not blocking passage. Hemidesmosomes tether cells to the basement membrane, not each other. Tight junctions' role in creating barriers, like in the blood-brain barrier, distinguishes them, making 'c' the correct junction type.