The Protection of the Body Flashcards
What is the epidermis made up of?
The epidermis is made up of stratified keratinised epithelial cells.
Where do the cells in the epidermis originate?
Cells in the epidermis originate from the basal layer, where there is continuous cell division.
What happens to older cells in the epidermis?
Older cells are pushed up further to the surface of the epidermis.
How do cells change as they move closer to the surface of the epidermis?
Cells become thinner and flatter as they move closer to the surface.
What replaces the cytoplasm in epidermal cells as they move up?
Cytoplasm is replaced by keratin.
What anchors the epidermis to the dermis?
Upward projections on the dermal layer anchor the epidermis in place.
What can move to the lower part of the epidermis?
Waste products and nutrients can move to the lower part of the epidermis.
How is the dermal papillae arranged in thicker skin?
In thicker skin, such as palms and soles of feet, the dermal papillae is arranged in parallel lines.
What is the composition of the dermis layer?
The dermis layer is elastic and tough, formed from connective tissue.
What fibers are found in the matrix of the dermis?
The matrix contains collagen fibers interlaced with elastic fibers.
What are the main cells found in the dermis?
Fibroblasts, Langerhans cells, and mast cells are the main cells in the dermis.
What do blood vessels in the dermis supply?
Blood vessels supply the sweat glands, sebaceous glands, and hair follicles.
What role do sensory nerve endings in the dermis play?
They detect changes in the environment, such as temperature, pressure, and pain.
What is the function of the Pacinian corpuscle?
The Pacinian corpuscle is sensitive to deep pressure.
What are the two types of sweat glands?
The two types of sweat glands are Eccrine sweat glands and Apocrine sweat glands.
Where are Eccrine sweat glands located?
Eccrine sweat glands are numerous and widely distributed, with ducts opening onto the skin surface.
What is the composition of sweat produced by Eccrine glands?
The sweat produced is clear and watery.
What is the primary function of Eccrine sweat glands?
They help regulate body temperature.
Where do Apocrine sweat glands open?
Apocrine sweat glands have ducts that open into hair follicles.
When do Apocrine sweat glands become active?
They become active during puberty.
What is the composition of sweat secreted by Apocrine glands?
The sweat secreted is more viscous and can cause unpleasant odors due to bacterial decomposition.
What do sebaceous glands secrete?
Sebaceous glands secrete sebum, an oily antimicrobial substance.
Where are sebaceous glands most numerous?
They are numerous in the face, scalp, and groin areas.
What is the function of sebum?
Sebum keeps hair soft and pliable and prevents skin from drying and cracking.
