Question

1. list the functions of the skin
2. if you had to pick a function that you felt was the most important, which would you pick? justify your response.
3. what is the function of the hypodermis
4. in which layer will striae (stretchmarks) appear?
5. how do stretch marks appear? what can cause them

Explanation:

1. The skin has functions such as protection (barrier against pathogens, UV - rays), temperature regulation (sweating, vasoconstriction/vasodilation), sensation (touch, pain, pressure), vitamin D synthesis, and excretion of small amounts of waste.
2. Protection could be considered most important as it safeguards the body from external threats like bacteria, viruses, and physical damage. Without it, the body would be highly vulnerable.
3. The hypodermis functions as insulation, energy storage (fat cells), and provides cushioning and attachment of the skin to underlying structures.
4. Stretch - marks (striae) appear in the dermis layer.
5. Stretch marks appear when the skin is stretched rapidly, causing damage to the collagen and elastin fibers in the dermis. Causes include rapid weight gain (e.g., during pregnancy or puberty), muscle growth from intense body - building, and certain medical conditions that affect connective tissue.

Answer:

1. Protection, temperature regulation, sensation, vitamin D synthesis, excretion.
2. Protection; it safeguards the body from external threats.
3. Insulation, energy storage, cushioning, attachment to underlying structures.
4. Dermis.
5. Appear when skin is stretched rapidly, damaging collagen and elastin fibers in the dermis; causes include rapid weight gain, muscle growth, certain medical conditions.