Dermatology Flashcards
What are the principal cells in the epidermis termed?
The epidermis is made up of 95% keratinocytes but also contains melanocytes, Langerhans cells, Merkel cells, and inflammatory cells. The stratum basale is primarily made up of basal keratinocyte cells, which can be considered the stem cells of the epidermis.
Describe the histology of the epidermis, relating structure to function
Epidermis: The upper or outer layer of the two main layers of cells that make up the skin. The epidermis is mostly made up of flat, scale-like cells called squamous cells. Under the squamous cells are round cells called basal cells. The deepest part of the epidermis also contains melanocytes.
. What features of the epidermis serve for protection?
the epidermis, is the thin, tough part of your body that acts like a protective shell. … That’s because the epidermis contains a layer of cells called stratum corneum, which are packed tightly to protect your body against the absorption of harmful substances.
Where in the body does non-keratinised stratified squamous epithelium occur?
In the oral cavity and esophagus, stratified squamous epithelia occur as a “mucous” or non-keratinized type, designed for protection and lubrication during chewing and swallowing.
What is keratin and what are its functions? In what ways is it adapted for these
functions?
Keratin is an important protein in the epidermis. Keratin has two main functions: to adhere cells to each other and to form a protective layer on the outside of the skin. In epithelial cells, keratin proteins inside the cell attach to proteins called desmosomes on the surface.
What is the muscle associated with hair follicles termed? What type of muscle is it?
What is its function?
Associated with each hair follicle is a bundle of smooth muscle cells called an arrector pili muscle.
- What TWO other structures are associated with hair follicles and what are their
functions?
the cup in which the follicle grows known as the infundibulum,[5]
the sebaceous glands,
and the apocrine sweat glands.
Hair follicle receptors sense the position of the hair.
What is the function of melanin and where is it principally located in the skin?
Melanin is produced by the oxidation of the amino acid tyrosine, followed by polymerization
Found in melanocytes
What is the pH of the surface of the skin and what causes it?
Our skin has a thin, protective layer on its surface, referred to as the acid mantle. This acid mantle is made up of sebum (free fatty acids) excreted from the skin’s sebaceous glands, which mixes with lactic and amino acids from sweat to create the skin’s pH, which ideally should be slightly acidic – at about 5.5
Where are sebaceous glands located in the skin?
Sebaceous glands secrete the oily, waxy substance called sebum that is made of triglycerides, wax esters, squalene, and metabolites of fat-producing cells. Sebum waterproofs and lubricates the skin and hair of mammals.
Can be filled with bacteria
What are the differences in structure, function and location of apocrine sweat glands
and eccrine sweat glands?
The differences between eccrine and apocrine sweat glands follow: (1) Eccrine sweat glands are never connected to hair follicles, whereas apocrine sweat glands are. (2) Eccrine sweat glands produce a watery secretion, whereas apocrine secretion is more viscid.
What are ceruminous glands and where are they located? What do they produce?
What is its function?
The ceruminous glands in the skin of the human external auditory canal are modified apocrine glands, which, together with sebaceous glands, produce the cerumen, the ear wax. Cerumen plays an important role in the protection of the ear canal against physical damage and microbial invasion.
What is a receptor? Name four different types of receptor found in skin and describe
their function?
The four different types of general sensory receptors include mechanoreceptors a sense organ or cell that responds to mechanical stimuli such as touch or sound.
, thermoreceptors, responds to temperature
chemoreceptor are sensory nerves of blood vessels where they detect changes in chemical concentrations.
and
nociceptors. - sense of pain
What are the effectors in temperature regulation?
. If body temperature rises above 37.2°C, activity in the control center targets two effectors: (1) muscle tissue in the walls of blood vessels supplying the skin and (2) sweat gland
What is the difference between a papule, macule and pustule?
A papule is an area of abnormal skin tissue that is less than 1 centimeter around. A papule has distinct borders, and it can appear in a variety of shapes. Papules are often called skin lesions, which are essentially changes in the color or texture of your skin. Sometimes, papules cluster together to form a rash
Macule is an area of skin discoloration.
A pustule is a small blister or pimple on the skin containing pus.
