41 Integument

Keratinocytes and melanocytes are derived from the ectoderm. Merkel cells originate from the neural crest.

A mutation in tyrosinase can lead to albinism. Faster degradation of melanin is what causes fair skin.

Which of the following is false?

The stratum lucidum is called this because the cells are almost transparent as the nucleus is disappearing. The stratum lucidum and granulosum are more defined in thin skin than they are in thick skin.

Merocrine secretion is seen in glands are associated with the hair follicle. Sweat glands engage in merocrine secretion.

Which of the following is incorrectly matched

Adrenergic stimulation is related to thermoregulatory activity of sweat glands. Emotional stimulation is cholinergic.

The secretory coils are found in the hypodermis. The clear part secretes the watery component of sweat and the dark cells secrete protein content.

Arrector pilli muscles associated with hair follicles are under involuntary control via the cortex. The hair cuticle is part of the external root sheath layer

Which of the following is incorrectly matched?

Papillary dermis is directly attached to the dermis, has looped capillaries, and supplies the epidermis. Reticular dermis is made of dense irregular tissues, elastic fibers, and glands.