Skin, Hair, and Muscle Structure Quiz

In most muscles, the origin is typically considered the upper attachment and the insertion is the lower attachment.

A fixator is a muscle that assists the prime mover by producing the opposite of the desired movement.

Muscles that prevent unwanted movement during an action are referred to as synergists.

The insertion of a muscle's tendon is almost always into the epiphysis near a joint.

Adductor magnus tendon insertion is unique because it is located on the metacarpals.

Muscle action involving bringing attachments closer together is known as isotonic contraction.

The upper end of the popliteus is unanimously considered the origin regardless of circumstances.

Cancellous bone is composed of trabeculae arranged randomly to resist strains and stresses.

The nerve to a muscle in the limb contains approximately 40% afferent fibers.

Third, fourth, sixth, and seventh cranial nerves supply the ocular and facial muscles with sensory fibers.

Proprioceptive impulses from the trapezius muscle are conveyed by C3 and C4.

At birth, the marrow in all bones is red and involved in active haemopoiesis.

Proprioceptive impulses from the tongue muscles are conveyed by the trigeminal nerve.

By adulthood, there is a microscopic difference between cancellous and compact bone.

The spinal part of the accessory nerve contains sensory fibers.

Yellow marrow found in adults has no haemopoietic activity.

Hair follicles continue to develop throughout an individual's lifetime, even after birth.

The skin is more firmly attached to the underlying structures along the flexure lines.

The sympathetic nerve supply affects the contraction of the arrector pili muscle, causing the hair to 'stand on end'.

Melanocyte activity in the hair matrix decreases with age, affecting hair color.

Sweat glands are evenly distributed over the skin, including areas like the lips and the tympanic membranes.

The claw hand deformity is due to the unopposed action of both the extensors and flexor digitorum profundus.

Wasting of interossei muscles results in a guttering appearance on the dorsum of the hand.

There is always significant sensory loss on the ulnar side of the hand after an ulnar nerve injury.

The median nerve can be exposed by incision along the medial border of the biceps.

To test the action of the ulnar nerve, abduction of the index finger by the first dorsal interosseous is examined.

Surgical relief of compression in the carpal tunnel is achieved by transversely incising the flexor retinaculum.

Flexor pollicis longus and finger flexors are tested by asking the patient to pinch together the pads of the thumb and index finger.

The ulnar nerve can be exposed in the upper arm along the lateral border of biceps.

A high lesion of the peripheral nerves affects the ulnar half of flexor digitorum profundus in flexing the distal interphalangeal joint of the little finger.