Chapter 5, Problem 1CP

What structures are included in the integumentary system?

Summary Introduction

To review:

The structures that are included in the integumentary system.

Introduction:

Integument means covering. Skin covers the entire outside of the body. The skin is only a few millimeter thick; still it is the largest organ in the body. The skin is called an organ because it consists of a variety of tissues and each of them has its own specific task.

It protects the body from different damages like loss of water or abrasion from outside.

Explanation of Solution

Integumentary system regulates body temperature, excretes wastes in the form of sweat, works as a shield and protects the body, and provides sensory information about the surrounding environment.

Skin: It is the largest organ of the body, also known as cutaneous membrane, which covers the external surface of the body. Skin protects the body from foreign particles and consists of two layers: epidermis (superficial layer) and dermis (deeper and thick connective tissue).

Hair: Hair is a fine thread-like strand growing on the dermis layer of the human skin and is made up of a protein called keratin. It is the first line of defense protecting the body from the foreign particles.

Nail: Nails are composed of dead and keratinized epidermal cells. Nails are essential for grasping things, and to clean the body.

Sebaceous glands: Sebaceous glands contain sebum, proteins, triglycerides, and inorganic salts. These glands are associated with hair follicles and cover the hair surface and prevent skin from drying. Majority of these glands are present in eyelids, labia majora, and lips. Sebaceous glands prevent the bacterial growth on skin.

Sweat glands: The primary function of sweat glands is to maintain temperature of the body. The main function of sweat glands is to excrete waste from the body and they are generally present in dermis and subcutaneous layer. These glands secrete water, sodium and chloride ions, urea, uric acid, and glucose.

Sensory receptors: The skin contains nerve receptors and endings; sensations arising from neuron stimulation in the skin are called cutaneous sensations. These include thermal sensations and pain.

Conclusion

The integumentary system includes skin, hair, nails, and sensory receptors.