Skin Integumentary System Review for Anatomy & Physiology

In your Anatomy & Physiology class, you will study the Integumentary system, which is a fancy word for the skin system. This study guide will help you learn what areas are important to study and what type of question you may have on an A & P lecture exam.

This study guide lays out the layers of the skin, appendages (hail, nails, hair follicles, sweat & sebaceous glands), the function of each appendage, and the sensory nerves (Meissner’s & Pacinian  Corpuscle) and more.

Also, you will be about to take a quiz which is similar to an Anatomy and Physiology exam.

Teaching Tutorial on Skin System

Study Guide for Anatomy & Physiology Skin System

The skin and its appendages make up the integumentary system. The skin is an organ that performs a vital function for our body. It helps our body control its temperature, protect us from UV radiation and other environmental hazards. In addition, the sensors in our skin keep us protected by making us aware of conditions that could harm us.

Skin is composed of 2 layers

1. Epidermis: The superficial layer
2. Dermis: a fibrous connective tissue that is below the epidermis
3. Hypodermis: NOT PART OF THE INTERGUMENTARY SYSTEM this is a fatty layer below the dermis

Let’s go over each part and talk about its function. Then we will do a little quiz.

First let’s look at the layers of the skin:

Epidermis: is a keratinized stratified squamous epithelium that contains four distinct types of cells: Keratinocytes, Melanocytes, Merkel Cells, and Langerhan Cells

Dermis: The second layer of the second and is strong flexible connective tissue. It contains nerve fibers and blood vessels. The dermis has two layers:

1. Papillary layer: the superficial which is 20% of the dermis and has dermal papillae that look like finger-like pegs that rests on the epidermis
2. Reticular Layer: this accounts for 80% of the dermis and is networks of collagen fibers.

Hypodermis: It is found below the skin and is not technically part of Integumentary system. It is made up of fat. This layer act as an insulator.

Now to the Appendages of the skin:

These appendages are found in the epidermis and dermis and include:

1. Hair & Hair Follicles
2. Sebaceous Glands
3. Sweat Glands
4. Nails

Hair: Function is to allow the body to sense things that lightly touch our skin and protect certain areas of our body from harm. Example: eye lashes from particles or nose hairs from lint we may inhale

Hair Follicles: extends from the epidermis into the dermis

Root Hair Plexus: this is a knot of sensory nerve endings the wrap around hair bulb. This is why you can feel when someone touches your hair.

Arrector Pili Muscle: Found with the hair follicle as a bundle of smooth muscle cells. This is produces “goose bumps” on the skin.

Sebaceous Glands: known as oil glands and produce an oily product call sebum. Found everywhere expect the palms and soles.

Sweat Glands: also called Sudoriferous glands which produce sweat. Found everywhere except nipples and parts of the external genitalia.

Two Types of Sweat Glands

1. Eccrine gland: duct of the gland runs to an opening on the skin called the pore to secrete sweat. They are the more numerous than other gland types
2. Apocrine glands (NOT ON THE DIAGRAM due to where they are found): found in the axillary, anal, and genital areas. Produce a special kind of sweat that contains fatty substances and proteins.

Meissner’s Corpusle: nerve ending in the skin that is responsible for sensitivity to light touch

Pacinian Corpuscle: nerve ending responsible for sensitivity to pain and pressure

Quiz on Skin System

1. What layer of the skin contains Keratinocytes, Melanocytes, Merkel Cells, and Langerhan Cells?
   1. Dermal Papillae
   2. Dermis
   3. Epidermis
   4. Hypodermis

   2. Which layer of the dermis account for 20% of the dermis and has finger-like pegs that lies next to the epidermis?

   1. Granular Layer
   2. Spiny Layer
   3. Basal Layer
   4. Papillary Layer

Take rest of the quiz here.

Answer Key:

2, 4