lect 3 pt 4

Hypodermis

The subcutaneous layer located beneath the skin.

Subcutaneous

Below the cutaneous membrane (skin).

Hypodermis part of skin?

No. It is located underneath the skin rather than being part of the skin itself.

Tissue found in hypodermis

Some areolar connective tissue and a large amount of adipose connective tissue.

Another name for hypodermis

The subcutaneous layer.

Hypodermic injections

Delivered into the hypodermis/subcutaneous layer.

Hypodermis usefulness for injections

It contains subcutaneous fat, where injected substances can be released.

What does superficial mean?

Toward or closer to the surface.

What does deep mean?

Farther below the surface.

Skin derivatives

Structures associated with the skin, including hair, nails, and glands.

Hair composition

Extruded keratin strands.

Effect of arrector pili muscle contraction

The hair stands on end.

Causes for hair standing on end

Temperature changes or emotional states can trigger the response.

Temperature regulation and standing hair

It can create a space that traps heat between the skin and the outside environment.

Limitation of heat-trapping in humans

Humans have relatively little body hair, so the effect is limited.

Nails definition

Scale-like modifications of the stratum corneum.

Main function of nails

They protect the distal tips of the digits.

Mammary glands presence

Yes. Both males and females have mammary glands.

Activation of mammary glands

In the presence of certain hormones, usually during pregnancy.

Mammary glands secretion

Milk to nourish young.

Location of ceruminous glands

Only in the ear canal.

Ceruminous glands secretion

Cerumen, commonly called earwax.

Sebaceous glands secretion

Sebum.

What is sebum?

An oily secretion.

Sebum release location

Into hair follicles.

Sebum function for hair

It helps lubricate the hair, although it also makes hair oily.

Sweat glands alternate name

Sudoriferous glands.

Types of sweat glands

Merocrine (eccrine) glands and apocrine glands.

Merocrine/eccrine sweat glands secretion and distribution

They secrete a watery, salty solution and are widely distributed throughout the body.

Primary function of merocrine/eccrine sweat glands

Thermoregulation through sweating and evaporative cooling.