Podcast
Questions and Answers
What are the two main layers of the skin?
What are the two main layers of the skin?
Epidermis and dermis
Which type of cells make up the outermost layers of the epidermis?
Which type of cells make up the outermost layers of the epidermis?
The dermis is the outermost layer of the skin.
The dermis is the outermost layer of the skin.
False
Which of the following is a type of gland found in the skin?
Which of the following is a type of gland found in the skin?
Signup and view all the answers
What are the appendages of the skin?
What are the appendages of the skin?
Signup and view all the answers
Where are sweat glands NOT distributed?
Where are sweat glands NOT distributed?
Signup and view all the answers
Nails are found on the ends of the ______.
Nails are found on the ends of the ______.
Signup and view all the answers
What is the function of sebaceous glands?
What is the function of sebaceous glands?
Signup and view all the answers
Match the skin structures with their characteristics:
Match the skin structures with their characteristics:
Signup and view all the answers
Study Notes
Structure of the Skin
- The skin, also known as the integument, is the outermost layer of the human body.
- It consists of two layers: the epidermis (superficial/outer) and the dermis (deeper/inner).
- The epidermis is a stratified squamous epithelium, meaning it is made up of multiple layers of cells.
- The outermost layer of the epidermis is composed of flat, dead, and transparent cells filled with keratin, known as cornified cells.
- The intermediate layers of the epidermis contain cells that change shape as they move towards the surface, gaining granules and manufacturing keratin while losing their nuclei.
- The basal or germinative layer is the innermost layer of the epidermis and is the source of the other layers. It contains cells capable of multiplication, ensuring constant renewal of the epidermis.
Dermis (Dermal Layer)
- Located beneath the epidermis, the dermis is dense fibrous connective tissue made of white and yellow fibers.
- The dermis has finger-like projections called papillae, extending into the epidermis to prevent slippage between the two layers.
- Contains blood vessels, lymph vessels, nerve endings, hair follicles, and glands.
Integumentary Derivatives
- Structures formed from the tissues of the integument, including glands, hairs, and nails.
- Often referred to as the appendages of the skin because they are attached to the integument proper.
Hairs
- Found over most of the body’s surface except for lips, palms, fingers, genitalia, soles, and toes.
- Hair follicle is formed by the extension of the dermis and epidermis into the surface of the body, potentially reaching the subcutaneous layer.
- The hair root is located at the base of the follicle, and the hair shaft grows out from it.
- The hair shaft is composed of cells from the outermost layer of the epidermis.
- Scalp and facial hairs grow continuously, while other body hairs grow to a fixed length.
- Genetics determines an individual’s hair types and patterns, including their sex.
Glands
- Two types: Sweat glands and Sebaceous (oil) glands.
Sweat Glands
- Consist of a coiled secretory portion and a wavy duct leading to the skin surface.
- The secretory portion resides in the dermis or deeper.
- Distributed over the body except for the lips, nail beds, external ear canal, and external genitalia.
Sebaceous Glands
- Produce an oily substance that lubricates the skin and hairs.
- Usually found as a part of hair follicles, with the oil draining into the follicle.
- Some areas without hairs have sebaceous glands that open directly onto the skin surface.
Nails
- Found on the ends of digits (fingers and toes) and protect those areas.
- Attached to the terminal phalanx (bone) of each digit.
- Composed of cornified outer cell layers of the epidermis.
- Grow continuously from their roots.
Skin Coloration
- Determined by a combination of red, black, and yellow pigments present in the skin.
- Proportions of these pigments determine individual skin tones.
Studying That Suits You
Use AI to generate personalized quizzes and flashcards to suit your learning preferences.
Related Documents
Description
Explore the intricate structure of the skin, including the roles of the epidermis and dermis. Understand how the layers interact to protect the body and maintain its functions. This quiz dives into the cellular makeup and renewal process of the skin's layers.
