Fibrous protein that gives skin, hair, hooves, wool, fur, nails, horns
More pressure creates more Keratin
What are Melanocytes?
Cells that make Melanin
Primarily in stratum melanin
What are Merkel cells?
Cells in the stratum basale used for light touch
In hands and feet
That are Langerhans' cells?
What are the layers of the epidermis?
(Stratum Lucidium )
What are the different forms of skin cancer?
Basal cell carcinoma
Squamous cell carcinoma
What is the two most common cause of cancer?
What is Squamous cell Carcinoma?
Cancer in the keratinocytes of the intermediate or transitional layers of the epidermis.
Acceleration of apoptosis is an important response of these cells to sun exposure. If apoptosis fails ten these cells can become abnormal and produce cancer
If caught early cure is good
Usually in exposed area
What is Basal cell carcinoma?
An Abnormal growth of the basal cells. These cells are normally proteted from UV exposure by the melanin secreted by nearby melanocytes. This form of cancer can usually be successfully treated surgically if caught in time. least malignant form
Found in sun exposed areas
What is Melanoma?
Cancer of the melanocytes which is the most dangerous because it often metastasizes to other tissues and organs.
Found in non-exposed areas
Systemic reaction to UV
What is the ABCD rule?
Used to identify Melanoma
What is Carotene?
A protein that causes the color orange.
What color skin makes V-D faster?
What does a deficiency in V-D cause?
How long does light and dark skin need to be in the sun for V-D?
Light - 30min
What is the Papillary layer of the skin?
Areolar connective tissue
What is Dermal papillae?
Upper edge of the papillary
Has capillary loops, nerve endings and Meissners corpuscles
What is are the dermal ridges?
Form epidermal ridges which are our finger prints.
What is the Reticular layer?
Dens, irregular connective tissue
What are the appendages of the skin?
Hair follicles and hair
What are Ecccrin glands?
Secrete sweat mostly
Cell does not expel
What are apocrine glands?
A type of Merocrine secretion
Nasty sweat, part of the cells goes
What are Ceruminous glands?
The glands that produce ear wax
What is the anatomy of a hair follicle?
What is a hair cuticle?
The outermost, heavily keratinized single layer of cells that overlap each other.
What attributes to red head color?
What is the cause of gray hair?
Loss of melanin and air bubbles in shaft
What is the anatomy of the nail?
Free edge of nail
Body of nail
Proximal and lateral nail folds
root of nail
Hyponychium (under the free edge of the nail)
What are the different types of cartilage?
What is Hyaline cartilage?
The most common type
Composed of chondrocytes and collagen
Articular, costal respiratory, nasal epiphyseal plates and embryonic tissue
What is elastic cartilage?
Like hyaline but also has elastin fibers
Better resists bending
Only in external ear and epiglottis
What is Fibrocartilage?
Compressible and resists tension
Has thick collagen fibers
Knee menisci, vertebral disks, pubic symphsis
What are the functions of the skeletal system?
movement mineral storage
hematopoiesis (blood production)
Bone gross anatomy?
What is the Periosteum?
Membrane on the outside of the bone
Does not cover the area of the joint
What are Sharpey's fibers?
Collagen fibers that secure the periosteum to bone
What is Red Marrow?
What is yellow marrow?
What is the Endosteum?
Like periosteum but lines the medullary cavity and trabecular
What is the diaphysis?
The shaft of the bone.
What is the Nutrient foramen?
Hole throughout the periosteum into the diaphysis
What is the Metaphysis?
Vague area b/n the diaphysis and the epiphysis
What is the epiphyseal plate?
Can be scene on the end of the bone
What is the Epiphysis?
The distal and proximal end of the bone.
What is an osteoblast?
Bone form in cell
Secretes the osteoid
What is an osteocyte?
Mature bone cell
What is an osteoclast?
Bone resorbing cells derived from monocytes
What is an Osteoprogenitor cell?
Derived from mesenchyme
Differentiate into osteoblasts
What is an Osteon?
Osteon is the structural unit of bone
It is the concentric hallow tube along the axis of the bone.
What is a Volkman's canal?
A canal that runs perpendicular to the osteons.
Has blood and nerves
What is the Haversian system?
The same as an osteon
What is a Canaliculi?
The fine lines perpendicular to the canal and lacunae
What is the lacunae?
The holes that contain the osteocyte
What is the lamella?
The part of the bone that cycles the central canal
What is intramembranous edification?
A model of fibrous connective tissue
Cranium (accept base occipital) and clavicle.
Clavicle is the first bone to ossify (day 39)
What is Endochondral ossification?
A model of Hyaline cartilage
Everywhere else but not superior half of occipital
What is Achondroplasia?
A disease that affects the endochondral ossification
What is the anatomy of the fetal skull?
When does the fetal skull ossify?
Normally by age 1
What are Wormian bones?
Also called ossicles bones.
Are irregular bones formed in the sutures
The fontanelles on the lateral side of the fetal head?
What is wolf's law?
Bone remodels in response to stressors
This is what produces all the little bumps and ridges under muscle attachments.