SC 1232 Study Guide Exam 2 Winter 2009

CHAPTER 6: INTEGUMENTARY SYSTEM by Kelly Robertson

Epidermis - is composed of 5 layers of stratified squamous epithelium. Cells begin mitosis in the bottom layer known as the stratum basale. Next the cells move up into the stratum spinosum which is a spiny layer that connects to the basement layer. Next the cells move up into the stratum granulosum where they develop granules of keratin. The cells are beginning a process of keratinization. They are actually in the process of dying. Next they move up into the stratum lucidum. This is the thickest layer and is found primarily on the palms and soles of the feet. Finally the cells push up into the stratum corneum. This is the outermost layer of the epidermis and his somewhat waterproof. The cells are fully keratinized, dead cells. There is no direct blood and nutrient supply to the epidermis.

Dermis - thicker than the epidermis and is made up of connective tissue, elastin and collagen. Also contains smooth muscle, nervous and blood tissue. The basement layer of the epidermis connects to the dermis.

Subcutaneous layer - (aka the hypodermis) is the layer that lies under the dermis. This is where the collagen and elastin fibers are found. This layer is also comprised of adipose (fat) tissue that insulates the body.

Keratinization - In this process skin cells produce a protein called keratin which begins to harden the cell. Keratinized cells are actually dead skin cells.

Melancocytes - cells that produce melanin (pigment) which is responsible for giving the skin its color. Melanin is the skins natural defense against UV rays. Melanocytes are found in the stratum basale. They are the only cells that can produce melanin, however the melanin does enter the nearby epidermal cells through cellular extensions that pass the melanin between the cells. Melanocytes are actually a type of nerve cell. Everyone regardless of race have the same number of melanocytes the difference is they just produce a different type of melanin.

Nails - protective, hardened keratin that forms at the ends of fingers and toes. Each nail has a nail plate and a nail bed. The whitish half moon called the lunula is the most active region of the nail giving rise to new cells constantly.

Hair follicle - a tube in which the hair develops. The follicle extends from the surface into the dermis and contains the hair root. The base of the follicle contains epidermal cells which receive nutrients from the dermal blood vessels.

Eumelanin - type of pigment found in dark hair that has a more brownish black color.

Pheomelanin - a type of pigment found in blonde and red hair that that has a more reddish-yellow color.

Sebaceous glands - glands that are associated with hair follicles and produce sebaceous fluid called sebum (oil) to protect the skin surface. They are holocrine glands .

Sudoriferous glands - (aka sweat glands) are coiled glands found in the dermis. They are lined with epithelial cells. The most numerous sweat glands are eccrine glands which respond to body temperature to cool the body. Eccrine glands are most abundant on the forehead, neck and back. They are also found on the palms and feet. Apocrine glands are sweat glands that develop a scent as the sweat mixes with bacteria on the body’s surface. Apocrine glands become active at puberty and are more associated with emotions, fright and pain.

Radiation - the primary means of body heat loss. The heat just radiates from the body by infrared heat rays.

Conduction - when heat moves from the body directly into the molecules of cooler objects. An example would be when a person’s head is lying on a fresh pillow that is room temperature which is cooler than body temperature. The heat from the person’s head begins to heat up the pillow by conduction.

Convection- when air that is cooler than the body temperature moves over the body surface it removes heat. This circulation of air over a warm surface is convection.

Evaporation - a means of heat loss that uses sweat glands to release sweat onto the surface of the body. The sweat heats up from body heat and turns from a liquid to a gas. This is called evaporation and in turn lowers the body temperature.

Inflammation - the body’s normal response to injury. When injury occurs the blood vessels in the area dilate and allow more fluids to enter. the skin may become reddened, swollen, warm and painful to the touch.

Hypothermia - abnormally low body temperature. The lower the body’s temperature the lower the metabolic rate. Less oxygen is required. If the temperature continues to drop uncontrollably the muscles will begin to contract involuntarily to try to generate body heat. If left untreated it can lead to mental confusion, lethargy, unconsciousness and possible organ failure.

Hyperthermia - when the body temperature is abnormally high. If the temperature becomes too high it will begin to disrupt metabolic processes and can denature proteins in the body. Fever is a special case of hyperthermia in which increased body temperature helps to destroy invading pathogens.

CHAPTER 7: SKELETAL SYSTEM by Kelly Robertson

Skeletal System - Supports the body and attaches to muscles to provide movement. Also protects internal organs. Bones of the skeleton also produce blood cells. Collagen gives bones their strength and resilience and inorganic salts harden the bone making it difficult to crush.

Long bones - have a long diaphysis (or shaft) between an epiphysis at each end, the epiphysis articulates with another bone. Examples of long bones include the femur (thigh bone), humerus (upper arm bone) and radius and ulna (lower arm bones).

Short bones - are cube like bones such as those found in the wrists and ankles.

Flat bones - are flat, plate like structures such as the ribs, scapula (shoulder blade) and some bones of the skull.

Irregular bones - come in a variety of shapes and usually have many connections to other bones. The vertebrae of the spine and many facial bones are considered to be irregular bones.

Sesamoid bones - (aka round bones) they are usually small and round and have many tendons. The patella (knee cap) is an example of a sesamoid bone.

Articular cartilage - hyaline cartilage that surrounds the epiphysis and articulates to other bones.

Diaphysis - the shaft of long bones. It is filled with bone marrow and adipose tissue. Bone marrow is where new blood cells are formed.

Epiphysis - the ends of the bones that is covered with hyaline cartilage and articulates with other bones.

Periosteum - is a tough, vascular covering of fibrous tissue that covers the outside of the bone. It is firmly attached to the bones and connects to tendons and ligaments. The high vascularity of the periosteum allows the bone to receive nutrients and when bone is damaged it is the periosteum that helps to repair and form new bone tissue.

Processes - are bony projections off of a bone that provide sites for attachment of ligaments and tendons.

Compact bone - tightly packed bone tissue that is inside of the diaphysis. (aka cortical bone) This type of bone has a continuous extracellular matrix.

Spongy bone - forms the epiphysis. (aka cancellous bone) within the thin layer of compact bone on their surface. Spongey bone consists of many branching platelets called trabeculae. It is composed of osteocytes and extracellular matrix.

Medullary cavity - found in the compact bone of the diaphysis it is a hollow chamber that is continuous with the spaces of the spongy bone.

Endosteum - inner covering of the bone. It is a thin membrane that contains osteocytes or bone cells that are located in the bony chambers called lacunae. These cells transport nutrients and wastes to and from nearby cells.

Marrow - specialized type of soft connective tissue that fills the medullary cavity. There are two types of marrow, Red and Yellow. Red Marrow forms new blood cells and Yellow Marrow stores adipose (fat) tissue in the bone.

Osteon - a cylinder shaped unit (aka Haversian system) WHen many of these units become cemented together they form the substance of compact bone.

Intramembranous bones - the broad, flat bones of the skull

Osteoblasts - bone building cells. they deposit a bony matrix around themselves. Spongy bone can later become compact bone as the spaces fill with bone matrix.

Endochondral bones - develop from masses of hyaline cartilage that are shaped like future bony structures such as when the fetal skeleton is developing.

Epiphyseal plate - as spongy bone is deposited in the diaphysis and in the epiphysis, a band of cartilage called the epiphyseal plate remains between the two ossification centers.

Osteoclasts - bones cells that breakdown the calcified matrix. These are large cells that originate from the fusion of single-nucleated white blood cells called monocytes. They secrete an acid that dissolves the inorganic component of the calcified matrix and their lysosomes digest the organic components. They phagocytize components of the bony matrix. After they have removed the damaged bone osteoblasts fill the area in with new bone tissue.

Bone remodeling - occurs throughout life as osteoclasts remove bone tissue and osteoblasts replace the tissue. In an adult 3% to 5% of bone calcium is exchanged in a year.

Growth Hormone - secreted by the pituitary gland stimulates the division of cartilage cells in the epiphyseal plates. Without the hormone pituitary dwarfism results. A person with this condition is very small but equally proportioned. An excess of the hormone causes pituitary gigantism which can cause growth to over 8 feet tall. In adults excess of the hormone causes acromegaly, in which the feet, hands and jaw become enlarged.

hematopoiesis - the formation of blood cells. (aka hemopoiesis)

Axial Skeleton - consists of bony and cartilaginous parts that support and protect the organs of the head, neck and trunk. The skull, hyoid bone, vertebral column and thoracic cage are all considered a part of the axial skeleton.

Skull - the cranium and facial bones. Protects the brain

Hyoid bone - located in the neck (forms Adam’s apple) It does not articulate with any other bones but does attach to muscles and ligaments. It supports the tongue and is an attachment for muscles of swallowing.

Vertebral column - (aka the spine) consists of many vertebrae separated by cartilaginous intervertebral discs. It can be divided into the cervical spine (7 vertebrae), the thoracic spine (12 vertebrae), The lumbar spine (5 vertebrae). it fuses into the Sacrum triangular structure which is found at the base of the vertebral column and is part of the pelvis and from there the tailbone or Coccyx is formed.

Thoracic cage - The thoracic cage protects the organs of the thoracic cavity and the upper abdominal organs and supports the pectoral girdle and upper limbs. It is composed of 12 pairs of ribs which articulate posteriorly with the thoracic vertebrae. It also includes the sternum (breastbone) where most of the ribs attach anteriorly. The thoracic cage also protects the viscera in the thoracic and upper abdominal cavities. Aids in breathing.

Appendicular Skeleton - consists of the bones of the upper and lower extremities. It includes the pectoral girdle (scapula and clavicle), upper and lower limbs and the pelvic girdle.

Pectoral girdle - formed by the scapula (shoulder blade) and the clavicle (collarbone). The pectoral girdle connects the bones of the upper limbs to the axial skeleton and aids in upper limb movements.

Upper limbs - the arms which consists of the humerus (upper arm bone), radius and ulna (lower arm bones) as well as the hands. Eight Carpals (cuboid bones) make up the wrist, 5 bones of the palms are called the metacarpals and the fourteen finger bones are the phalanges.

Pelvic girdle - formed by the two hip bones and attached to each other anteriorly. Connects the bones of the lower limbs to the axial skeleton and, with the sacrum and coccyx forms the pelvis.

Lower limbs - each consists of the femur (thigh bone) and two lower leg bones the tibia and fibula. The femur and tibia articulate to form the tibiofemoral joint or the knee joint. Here the patella (knee cap) covers the anterior surface. There are 7 tarsals (cuboid bones) of the ankle. Five metatarsals (bones of the instep of the foot) and 14 phalanges that form the toes.

Mandible - the lower jaw bone that attaches to the skull by ligaments. Articulates with the temporal bones and provides attachments for the muscles of mastication.

Cranium - encloses and protects the brain. Some of the cranial bones contain air-filled sacs called paranasal sinuses. Sinuses reduce the weight of the skull and increase the intensity of the voice.

Frontal bone - the forehead bone that also forms part of the eye sockets and the roof of the nasal cavity. It is a single bone in adults but develops in two parts.

Parietal bones - located on each side o the skull just behind the frontal bones. they form the sides and roof of the cranium. they are fused together in the middle along the sagittal suture and meet the frontal bone at the coronal suture.

Occipital bone - this bone joins the parietal bones along the lambdoid suture. It forms the back of the skull and the base of the cranium. It includes a large opening called the foramen magnum in which the brainstem passes through to connect to the spinal cord.

Temporal bones - bones on each side of the skull that joins with the parietal bone at the squamous suture.

Sphenoid bone - situated at the base of the skull in front of the temporal bone and basilar part of the occipital bone. The sphenoid bone is one of the seven bones that articulate to form the orbit. Its shape somewhat resembles that of a butterfly.

Ethmoid bone - bone in the skull makes up the orbit of the eye and separates the nasal cavity from the brain. It is located at the roof of the nose between the two orbits. The cubical bone is lightweight due to it being a spongy bone. The ethmoid bone is one of the bones that makes up the orbit of the eye.

Facial skeleton - consists of 13 immovable bones and a moveable lower jawbone (mandible)

Maxillary bone - the bone of the upper jaw. . contains the sockets of the upper teeth. inside the maxillae, lateral to the nasal cavity are the maxillary sinuses.

Palatine bones - “L” shaped bones located behind the maxillae. the horizontal portions form the posterior section of the hard palate and the floor of the nasal cavity. The perpendicular portions help form the lateral walls of the nasal cavity.

Zygomatic bones - the cheek bones. they also help form the lateral walls and the floors of the orbits. Each bone has a temporal process which extends posteriorly to join the zygomatic process of a temporal bone.

Lacrimal bones - thin, scalelike structure located in the medial wall of each orbit between the ethmoid and the maxilla. It provides a pathway for a channel that carries tears from the eye to the nasal cavity.

Nasal bones - long, thin and nearly rectangular. lie side by side and are fused at the midline. they form the bridge of the nose and attachment site for the cartilaginous tissue that forms the shape of the nose.

Vomer bone - thin, flat bone located along the midline within the nasal cavity. posteriorly, it joins the perpendicular plate of the ethmoid bone, and together they form the nasal septum.

Inferior nasal conchae - fragile, scroll shaped bones attached to the lateral walls of the nasal cavity. they are the largest of the conchae and are below the superior and middle nasal conchae of the ethmoid bone.

Fontanels - (soft spots) in the skull of newborns. They permit some movement between the bones so that the developing skull is partially compressible and can change shape.

Vertebral column - extends from the skull to the pelvis and forms the vertical axis of the skeleton. it is composed of many bony parts called vertebrae. Supports the head and trunk but is flexible enough to permit movement. It also protects the spinal cord which passes through a vertebral canal formed by openings in the vertebrae.

Sternum - (aka breastbone) located along the midline in the anterior portion of the thoracic cage. It is a flat, elongated bone that develops in three parts: the manubrium (upper), the body (middle) and the xiphoid process (lower) which projects downward.

Pectoral girdle - (aka shoulder girdle) is made up of four parts. Two clavicles and two scapulae. It is an incomplete ring that is open in the back between the scapulae and the sternum and separates its bones in front. it supports the upper limbs and is an attachment for several muscles that move them.

Clavicles - slender, rod-like bones with elongated s-shapes. located at the base of the neck and run horizontally. Braces the freely movable scapulae and helps to hold the shoulders in place.

Scapulae - broad, somewhat triangular shaped bones located on each side of the upper back. They have flat bodies with concave anterior surfaces. The posterior surface of each is divided into unequal portions by a spine. The scapula has three borders, the medial (vertebral) border, the lateral (axillary) border and the superior border on the superior edge.

Humerus - long bone of the upper arm that extends from the scapula to the elbow. At its upper end is a smooth, rounded head that fits into the glenoid cavity of the scapula.

Radius - lower arm bone located on the thumb side. extends from the elbow to the wrist and crosses over the ulna when the hand is turned so the the palm faces backward. It is the shorter of the two lower arm bones.

Ulna - the longer of the two lower arm bones. It overlaps the end of the humerus posteriorly.

Carpal bones - 8 small cuboidal bones that make up the wrist. The bones mass together to form the carpus which articulates with the radius and the fibrocartilaginous disc on the ulnar side.

Metacarpal bones - the 5 bones that make up the palm of the hand. The bones are cylindrical with rounded distal ends that form the knuckles of a clenched fist. They articulate with the carpals and distally with the phalanges.

Phalanges - 14 bones that make up the fingers. There are three in each finger and two in the thumb.

Pelvic Girdle - consists of the two hip bones, (aka Coxal or innominate bones). they articulate with each other anteriorly and with the sacrum posteriorly. The sacrum, coccyx and pelvic girdle all form the bowl-shaped pelvis. the pelvic girdle supports the trunk of the body; provides attachments for the lower limbs; and protects the urinary bladder, the distal end of the large intestine and the internal reproductive organs. The body’s weight is transmitted through the pelvic girdle to the lower limbs and then onto the ground.

Hip bone - three parts the ilium, ischium and pubis.

Ilium - the largest and most superior portion of the hip bone. flare outward forming the prominence of the hip. The margin of this prominence is the iliac crest. Posteriorly the ilium joins the sacrum at the sacroiliac joint (SI joint). The greater sciatic notch is located on the posterior border of the ilium it is here where nerves and blood vessels pass.

Ischium - forms the lowest portion of the hip bone. It is “L” shaped with its angle, the ischial tuberosity pointing posteriorly and downward.

Pubis - constitutes the anterior portion of the hip bone. The two pubic bones come together at the midline to form a joint called the pubic symphysis.

Femur - (thigh bone) is the longest bone in the body and extend from the hop to the knee. The large, rounded head at its proximal end projects into the acetabulum of the hip bone.

Tibia - (shin bone) the longer of the two lower leg bones. It’s proximal end articulates with the condyles of the femur. A process called the tibial tuberosity provides an attachment for the patellar ligament. At it’s distal end it articulates with the medial malleolus (inner ankle). on the lateral side is a depression that articulates with the fibula.

Fibula -located on the lateral side of the tibia, with which it is connected above and below. It is the smaller of the two bones. It forms the lateral part of the ankle joint.

Tarsals - 7 bones that make up the Tarsus or talocrural joint (ankle joint). Of these bones the talus can move freely where it joins with the tibia and fibula. The other tarsals are firmly bound and support the talus.

Calcaneus - the largest tarsal bone. (aka heel bone) It helps support the body weight and provides attachment site for muscles that move the foot.

Metatarsal bones- 5 elongated bones that make up the instep of the foot. They articulate with the tarsus. Numbered 1 to 5 beginning on the medial side.

Phalanges - similar to the phalanges of the fingers but the phalanges of the toes are shorter. Each toe has 3 phalanges except the great toe which has 2.