The indegument (Skin) and the appendages (outgrowths) of the skin, like the hair, nails,

mammary, sweat and sebaceous glands

1. Keratinocyte (makes keratin, and is most abundant)

2.Melanocyte (makes melanin that provides UV protection)

3. Merkal cell (disk, deals with touch perception: associated with a nerve)

4. Langerhans Cell (has an immune function)

it is the stratum basale- 1st cell layer

stem cells- give rise to keratinocytes

Melanocyte (10-25%) only in Stratum Basale

Merkel Cells

Connective tissue divided into 2 basic layers:

The papillarylayer, which contains areolar LCT (20% of the dermis)

  The reticular layer, which contains DICT (80% of the dermis.

It contains 5% of the blood vessels which helps with thermo regulation

Outgrowths/downgrowths of the epidermis (epithelium) that are always associated with connective tissue.  They consist of:

Nail and hair (made from hard keratin)

 Sebaceous glands and sweat glands

Shaft= above skin

Root= below skin

Simple coiled tubular gland that release sweat (99% H2O, ions, urea)

They function to cool the body and extrete

the eccrine glands, the normal sweat glands which have a general distribution over the body

the apocrine glands release sweat that also contains fats and proteins, and have a limited distribution on the body (the perineum and the axilla (the anus and external genetalia and the arm pits))

Cartilage (Chondro-) has a firm but wet (70% H20) matrix with no blood vessels and no nerves, that contains delicate callogen fibrils and proteoglycans, and it resists compression. Chondrocyte is the cell in cartilage located in a lacuna, it has no intercellular connections.  Surrounded by the Perichondrium

 Describe the perichondrium

Hyaline (glassy) Cartilage - most abundant and studied, serves as model.  No fibers are visible, and it has a smooth appearance.  They are articular cartilage and Growth plates, and most of the fetal skeleton.

Elastic cartilage (modified Hyaline)- abundant elastic fibers, visible. Flexible and can bend, found in the outer ear, and epiglotis.

 Fibrocartilage (fibro=callogen fibers, modifified hyaline, mix between hyaline cart and DRCT)- has an abundance of callogen fibers. On pubic symphisis, intervertebral disc, and meniscus.

Compact Bone - External, looks solid, surrounded by the periosteum. Contains osteons (haversian systems) which run parallel to the long axis of bone. the matrix is highly organized to resist twisting.

Spongy bone -  internal, looks like a sponge, is covered by the endosteum, it is organized in tension line. Has holes and no osteons (no need for BV). Is lamellar bone, which has osteoblasts on it.

it is a membrane that surrounds the external surfaces of the bone except where there is articular cartilage, attached by sharpeys fibers (callogen) and has 2 layers.

The outer fibrous layer is DICT which houses blood vessels and nerves

The inner cellular layer houses osteoprogenitor cells, osteoblasts, and osteoclasts, the cells used for growth and remodeling

Osteoblast deposits bone ECM

Osteoclast breaks bone down ECM

They are the junctions between osteocytes and ostecytes, and osteoblasts and osteocytes.

1. Osteo progenitor cell young version of

2. osteoblast young version of

3. osteocyte the mature cell.

osteoclast

Organic includes cells, the matrix (callogen fibers) that provides tensile strength, some ground substance, and makes up 35% of the bone tissue

Inorganic includes the matrix which is composted of hydroxyapatite crystals (calcium and phosphate) and calcium and phosphate in non-crystalline form, and compose 65% of the bone tissue Both are extremely important for the physical properties of bone

Intramembranous = within the membrane of mesenchyme where there is no cartilage involved, flat bones, mesenchyme --> osteoblasts --> bone

Endochondral = most common, uses hyaline cartilage. Mesenchyme --> a hyaline cartilage model --> Cartilage matrix calcifies, cells die, and cavity is formed --> periosteal bud invade – bv osteoproginator cells, and osteoclasts --> bone deposited on calcified cartilage --> Cartilage remains at the articular surface and at the growth plates

There is a resting zone (reserve of cartilage)

A growth (proliferation) zone where cartilage cells undergo mitosis

Hypertrophic zone where older cartilage cells enlarge

The calcification zone where matrix becomes calcified and cartilage cells die

Ossification zone where new bone formation occurs

Synarthrosis (no movement)

Amphiarthrosis (some movement)

Diarthrosis (freely movable, most abundant)

Fibrous (DCT callagen fibers, no joint cavity)

Cartilaginous (cartilage, no joint cavity)

Synovial (Articular capsule, most abundant, has cavities with synovial fluid)

Sutures=skull

Gomphosis=point where tooth fits socket

 Syndesmosis=ligament, short or long callogen fibers

1. Articular (hyaline) cartilage

2. Articular capsule (fibrous capsule and synovial membrane)

3. Joint cavity (contains synovial fluid)

4. Ligament

5. BV and nerves

Capsule ligaments are thickenings of fibrous articular capsule, and are not dissectable

Extra/intracapsular can be dissected, extracapsular being outside the capsule, and intracapsular running through the joint cavity

Articular discs which are a meniscus made of fibrocartilage. They improve the fit, allow for 2 different movements in 1 joint, and absorb shock

Bursae and tendon sheaths function to reduce friction, both being bags of synovial fluid. Bursae is the most common, and tendon sheaths are only found around tendons.

1. Gliding – the sliding of flat bones

2. Angular- changing the angle between the bones and the joints

3. Rotational – turn/rotate around the long axis of the bone

Flexion means moving towards the joint, Dorsiflexion means moving the muscle away from the joint

Abduction means moving away from the midline, adduction means moving towards the midline

Circumduction means a cone in the air, combining the 4 other angular movments

1. Plane joints

2. Hinge joints

3. Pivot joints

4. Condyloid joints

5. Saddle joint

6. Ball and socket joint

1.Articular surfaces

2.Ligaments (more ligaments more stability)

3. Muscle tone- constant low level contraction of muscles whose tendons cross the joint

Intracapsular = anterior and posterior cruciate

Extracapsular = Medial and lateral collaterals (tibular and fibular respectively), and the arcuate and oblique popiteal