anatomy and physiology Flashcards
What is hair composed of?
Keratinized cells
What are the types of hair?
- Lanugo hair
- Vellus hair
- Terminal hair
What is the role of carotene?
A pigment contributing to the yellowish hue in lighter skin
What is the effect of UV radiation on skin color?
Stimulates melanocytes to produce more melanin
What are the histological characteristics of nails?
- Nail plate made of keratinized epithelial cells
- Nail bed consists of an epidermis with keratinocytes
What are freckles?
Small flat spots caused by increased melanin
What is a blister?
Raised fluid-filled sacs that form on the skin surface
What are stretch marks?
Linear streaky scars that appear on areas that have stretched rapidly
What are keloids?
Raised thick scars formed from excessive collagen production
What is the primary cause of leprosy?
Mycobacterium leprae
What is the significance of the lunula?
The area where new nail cells are formed
What are calluses?
Thick hard areas of skin caused by prolonged pressure or rubbing
What is a ball-and-socket joint?
A joint where the spherical head of one bone fits into a cup-like depression of another bone, allowing for a wide range of motion.
Give an example of a ball-and-socket joint.
Shoulder and hip.
What is a hinge joint?
A joint where a convex bone surface fits into a concave bone surface, allowing movement in one direction.
Give an example of a hinge joint.
Elbow, knee, fingers, toes.
What is a pivot joint?
A joint where a rounded or cylindrical bone fits into a ring-shaped bone and ligament structure, allowing rotation around a single axis.
Give an example of a pivot joint.
Neck.
What is a condyloid/ellipsoidal joint?
A joint where an oval-shaped condyle fits into an elliptical cavity, allowing movement in two planes.
Give an example of a condyloid joint.
Wrist and knuckles.
What is a saddle joint?
A joint where a concave surface fits into a convex surface like a saddle, allowing movement in two planes but is more flexible.
Give an example of a saddle joint.
Thumb.
What is a gliding/plane joint?
A joint with flat or slightly curved surfaces allowing bones to slide over each other.
Give an example of a gliding joint.
Wrist and ankle.