The Integumentary System Made up of...

The skin, hair, nails, sebaceous glands, cerminous or wax glands in the ear canal, and sweat glands.

Skin

The layers of the skin...

Skin

The layers of the skin...

The Stratum Corneum

The layers of the skin...

The Stratum Germinativum

(Melanocytes)

• ____ produce melanin.  This pigment is responsible for skin color and protection from the harmful ultraviolent rays of the sun.

• Dark-skinned individuals have more active _______.

• Albinism is a genetic condition that results from the absence of melanin.

The layers of the skin...

The Dermis aka Corium

• The ___ is also called the ___ or true skin and is composed of dense connective tissue.

• Blood and lympth vessels, nerves, muscles, glands, and hair follicles are found in the ____.

The Accessory Structures of the Skin

Hair

• ____ covers the entire body except the palms of the hands, the soles of the feet, and parts of the external genitalia.
• Each individual ___ is made of 3 parts: the outer cuticle; the cortex, which is the principal portion with pigment granules; and the inner medulla with air spaces.
• The visable portion of the ___ is called the shaft.
• The root of the ___ is in a ____ follicle.
• When the arrector pili smooth muscle contracts, it causes hair to stand on end and produces "goose bumps/flesh".

The Accessory Structures of the Skin

Hair Texture

The Accessory Structures of the Skin

Hair growth

The Accessory Structures of the Skin

Hair Color

• ___ ___ is determined by complex genetic factors.

• Gray hair occurs when pigment is absent in the cortex.

• White hair results from both the absence of pigment and air bubbles in the shaft.

• Heredity and other unknown factors cause hair to turn gray.

The Accessory Structures of the Skin

Nails

• A ___ is a modification of the epidermal cells made of very hard keratin.

• The ___ grows from the nail bed.

The Accessory Structures of the Skin

Sebaceous Glands

• Sebum, an oil, gives a cosmetic gloss to skin and moisturizes it.

• ____ secretion is controlled by the endocrine system, increasing during puberty and late pregnancy and decreasing with age.

The Accessory Structures of the Skin

Sweat Glands

• ___ ___ are most numerous in the palms of the hands and in the soles of our feet.

• The odor of sweat is produced by the action of bacteria feeding on the sweat.

• Sweating is an important physiologic process that helps cool the body.

Function of the Integementary system

Skin

Function of the Integementary system

Sensation

• Receptor sites for changes in temperature (hot and cold) and pressure (pleasure and pain) are found in the skin.

• Combinations of stimulations result in the sensation of itching, burning, and tickling.

Function of the Integementary system

Protection

• The skin prevents the entrance of harmful physical and chemical agents into the body.
• Melanin protects us from harmful ultraviolent rays of the sun.
• The lipid content of the skin prevents excessive water and electrolyte loss.
• The acidic pH of skin kills most bacteria and microorganisms that come in contact with our skin.
• Hair acts as an insulator, protects our eyes, ands filters out foreign particles in our nose.

Function of the Integementary system

Thermoregulation

• Normal body temperature is regulated by blood vessel dilation and constriction in the dermis of the skin.

• Sweating is an evaporation process that cools the body.

Function of the Integementary system

Secretion

• Sebum has antifungal and antifbacterial properties.

• Sweat contains waste products such as urea, uric acid, and ammonia, so it is also an excretion.

• The skin helps manufacture vitamin D through exposure to ultraviolent rays of the sun.

Skeleton

• The ___ is the supporting structure of the body; it allows muscles to bring about movement and breathing.

• The solid appearance of bone is due to mineral salts that form the inorganic matrix surrounding the living bone cells.

• Leonardo de Vinci was the first to correctly illustrate the 206 bones of the body.

The Function of the Skeletal System

The skeleton has 5 functions

• Support surrounding tissues

• Protect vital organs and soft tissues

• Provide levers for muscles to pull on

• Manufacture blood cells in red bone marrow by hematopoiesis

• Act as a storage area for mineral salts, especially calcium and phosphorus, and fat in yellow marrow.

The Growth and Formation of Bone

• After 3 months, the fetal skeleton is completely formed and made primarily of hyaline cartliage. Ossification and growth then development.

• Longitudinal growth of bone continues until approximately 15 years of age in girls and 16 in boys.

• Bone maturation continues until 21 years of age in both sexes.

The Growth Formation of the Bone

Deposition of the Bone

• Bone develops from spindle-shaped embryonic bone cells called osteoblasts
  Osteoblasts develop into mature bone cells called osteocytes. They form under the fibrovascular membrane covering bone, called the periosteum, and under the membrane lining of the medullary cavity, called the endosteum.
• The more strain or pressure on a bone, the more the bone will develop.
• Osteoclasts are large cells that are responsible for the reabsorption of injured bone. They also reabsorb bone during remodeling.

The Growth and Formation of Bone

Types of Ossification

• Intramembranous ossification: a process in which dense connective membranes are replaced by deposits of inorganic calcium salts. The bones of the cranium form in this way.

• Endochondral ossification: the process whereby cartilage is the environment in which the bone cells develop. All other bones of the body develop this way.

The Growth and Formation of Bone

Maintaining the Bone

• The correct amount of calcium stored in the bones, the proper amount of calcium in the blood, and the excretion of excess calcium are controlled by the endocrine system.

• The parathyroid glands secrete parathormone, which causes calcium to be released into the bloodstream. Another hormone, calcitonin, causes calcium to be stored in the bones.

The Histology of Bone

There are 2 types of Bone Tissue

• Compact or dense bone is strong and solid.

• Cancellous or spongy bone has many open spaces filled with bone marrow.

The Histology of Bone

Bone Marrow

There are two types of bone marrow:

• Red Bone Marrow's function is hematopoiesis, the formation of Red Blood cells.
• In an adult the ribs, vertebrae, sternum, and pelvis contain Red Bone Marrow in their cancellous tissue.
• Yellow Bone Marrow is found in the shafts of long bones within their cancellous tissue.
• Yellow Bone Marrow stores fat cells.

The Classification of Bones

The bones in the body can be classified, based on shape, into five categories

The Classification of Bones

The bones in the body can be classified, based on shape, into five categories (continued....)

4. Irregular bones have a very peculiar or irregular shape. Examples are the vertebrae and the ossicles of the ear.

5. Sesamoid bones are small rounded bones enclosed in tendon and fascial tissue near joints. One example is the largest sesamoid bone, the patella.

Bone Markings

• Bones exhibit certain projections called processes. Examples of processes are the spine, condyle, tubercle, trochlea, trochanter, crest, line, head, and neck.

• Bones also exhibit certain depressions called fossae. Examples of fossae are suture, foramen, meatus, or canal, sinus or antrum, and sulcus.
  
  
• These markings are functional to help join bones to one another, to provide a surface for muscle attachment, or to serve as a passageway for blood vessels and nerves into and out of the bone.

Divisions of the Skeleton

• The human skeleton has 206 bones.

• The skeleton can be divided into the axial skeleton (skull, hyoid, vertebrae, ribs, and sternum) and the appendicular skeleton (bones of the upper and lower extremities).

The Axial Skeleton

The Orbits, Nasal Cavities, and Foramina

• The orbits are the two deep cavities that enclose and protect the eyes.  A number of bones of the skull contribute to their formation.

• The framework of the nose surrounds the two nasal cavities made by a number of bones of the skull.

• Foramina are passageways for blood vessels and nerves. The largest foramen of the skull is the foramen magnum for passage of the spinal cord.

The Axial Skeleton

The Hyoid Bone

• The hyoid bone does not articulate with any other bones. It is suspended by ligaments from the styloid process of the temporal bone.

• Its function is to support the tounge.

The Axial Skeleton

The Torso or Trunk

• The sternum, ribs, and vertebrae make up the torso or trunk.

• There are 7 cervical vertebrae: the first is called the atlas and the second the axis.

• There are 12 thoracic vertebrae that articulate with the ribs.

• There are 5 lumbar vertebrae, the strongest.

• The single sacrum is made of 5 fused sacral vertebrae.

The Axial Skeleton

The Torso or Trunk (continued....)

• The single coccyx or tailbone is made up of 4 fused coccygeal vertebrae.

• The sternum or breastbone develops in 3 parts; it looks like a sword: the manubrium or handle, the gladiolus or body that looks like the blade, and the xiphoid process that resembles the tip of the sword.

• There are 12 pairs of ribs: the upper 7 pairs articulate directly with the sternum through their costal cartilages and are called true ribs; the lower 5 pairs are called false ribs; because the 11th and 12th pairs have no costal cartilage to articulate indirectly with the sternum like the 8th, 9th, and 10th pairs, they are called floating ribs.

The Appendicular Skeleton

The Bones of the Upper Extremities

• The bones of the shoulder girdle are the clavicle or collarbone and the scapula or shoulder blade.

• The humerous is the bone of the upper arm.

• The forearm bones are the ulna, the longer of the two bones, with its proximal olecran process or funny bone of the elbow, and the radius, the shorter bone that articulates with some of the wrist or carpal bones.

The Appendicular Skeleton

The Bones of the Upper Extremities (continued...)

• The carpal bones of the wrist are the pisiform, triquetral, lunate, and scaphoid (in the proximal row); the hamate, capitate, trapezoid or lesser multiangular; and the trapezium (type) or greater multiangular (in the distal row).

• The bones of the palm of the hand are the five metacarpals.

• The bones of the fingers are the 14 phalanges in each hand.

The Appendicular Skeleton

The Bones of the Lower Extremities

• Each hip or pelvic bone consists of 3 fused bones; the ischium, ilium, and pubis. They form the pelvic girdle. The female ilium is wider than the male's, and we all sit on our ischial tuberosity.

• The femur or thighbone is the largest bone in the body.

• The patella or kneecap is the largest of the sesamoid bones; it is wrapped in the tendon of the quadriceps femoris muscle.

• The tibia or shinbone is the largest bone of the lower leg.

The Appendicular Skeleton

The Bones of the Lower Extremities (continued...)

• The fibula of the lower leg is the most slender bone in the body. It is also known as the calfbone.

• The tarsal bones of the foot are the calcaneus or heel, the talus or ankle, the navicular, and the 3 cuneiforms.

• The metatarsals make up the rest of the foot bones along with 14 phalanges of the toes.

The Arches of the Foot

• The foot has 3 arches: the medial longitudial arch is the highest, the lateral longitudinal arch, and the transverse arch.