Chapter 32.1, Problem 4MI

Summary Introduction

To write:

The correct vocabulary term for the given definitions.

Introduction:

The largest organ of the body is the skin. It has 20 square feet of total area. Its main function is to protect animals from microbes, harmful elements, regulate the body temperature, and allows sense of touch, cold, and heat.

Explanation of Solution

Melanin − It is a pigment manufactured by cells in the inner layer of epidermis that protects from ultraviolet radiations and affects skin color. It is formed by the process of melanogenesis, where tyrosine amino acid is oxidized and then polymerized.

Sebaceous gland − It is the structure that produces oil that lubricates skin and hair. This is an exocrine gland that opens into a hair follicle.

Keratin − It is a protein found in the outer layer of epidermal cells that waterproofs and protects the cells and tissues underneath. It is a protective layer that cannot be easily teared or scratched.

Hair follicles − Narrow cavity in the dermis from which hair cells grows. Hair starts to grow from the bottom of hair follicle.

Epidermis − It is the outer superficial layer of skin. It acts as a barrier for pathogens that cause infection and regulate release of water from the body.

Dermis − It is the inner and thicker layer of skin. It is the thickest layer and is composed of elastic and fibrous tissue. It functions to provide strength and flexibility to the skin.