By: Lauren Reyner, Brittany Mindt, Dominique DiBernardo

 Axial Skeleton- supports the central axis of the body  Appendicular Skeleton- Formed by the bones of the arms and legs, along with the bones of the pelvis and shoulder area  Haversian Canals- Compact bone in channels in which nerves and blood vessels run through  Bone marrow- cavities that contain a soft tissue  Cartilage- type of connective tissue  Ossification- Process of bone formation in which cartilage is replaced by bone.  Osteoblasts- secrete mineral deposits that replace the cartilage in developing bones  Osteoclasts- cells that break down bone minerals  Ligaments- tough connective tissue that is attached to the membranes that surround bones.

 Functions: Supports the body Protects internal organs Assists movement Stores minerals Blood cell formation Disorders: - Arthritis- Inflammation of a joint - Osteoporosis- Loss of calcium leads to weakening of bones

 Made of approximately 206 bones  Bones attached to muscle by tendons  Bones held together by Ligaments

 Bones are a solid network of living cells and protein fibers that are surrounded by deposits of calcium salts.  The skeleton of a human embryo is composed almost entirely of cartilage.  Spongy Bone- can support a lot of force and red bone marrow is found in the spaces of spongy bone.  Compact bone- Found under the periosteum, contains networks of tubes through which blood vessels and nerves travel.  Yellow marrow- mainly made of fat cells  Red Marrow- Produces blood cells

 Joint- a place where one or more bones meet another bone  Joints contain connective tissues that hold bones together  Joints permit bones to move without damaging each other.  Types of Joints:  Immovable(fixed Joints)- Allow no movement. Joints are interlocked and fuse together ex. Skull  Slightly Movable- allow small amount of movement ex. Lower leg  Freely Movable- allow movement in two or more directions  Wear and tear over the years leads to osteoarthritis

 Muscle- Bundles of fibers that work together to allow for structure and movement  3 types:  Skeletal- Attaches to bones and moves them. Voluntary.  Smooth- Controls breathing and digestive system. Involuntary.  Cardiac- Found only in the heart. Involuntary.

 Myofibrils- tightly packed filament bundles  Myosin- thick filaments of protein  Actin- thin filaments of protein  Sarcomere- two Z lines and filaments between them  Neuromuscular Junction- a synapse  Acetylocholine- neurotransmitter  Tendons- connective tissue that join skeletal muscles and bone

 During a muscle contraction, myosin filaments form cross- bridges with actin filaments. The cross- bridges then change shape, pulling actin filaments towards the center of the sarcomere.

 Skeletal muscles generate force and produce movement by pulling the body parts as they contract  Flexor- Decrease angle between bones (biceps)  Extensor- Increase angle between bones (Triceps)  Muscles work together- One contracts while the other relaxes

 The Integumentary system serves as a barrier against infection and injury, helps to regulate body temperature, removes wastes from the body, gathers information, and produces vitamin D

 Epidermis- Outer Layer  Inner layer- Living cells  Outer layer- Dead cells Contains:  Keratin- Waterproofing  Melanocytes- produces pigment

 Dermis- Middle layer- Irregular ridges between dermis and epidermis form fingerprints  Contains:  Hair follicles/Roots  Sweat glands  Sebacious(oil) glands  Arrector pili Muscle  Nerves  Blood vessels

 Hypodermis- Innermost layer  Contains: Adipose(fat) cells- Cushions, insolates Blood Vessels- Temperature regulation, nutrients Nerves- Pressure, pain

 Acne- Develops when sebum and dead skin cells form plugs in hair follicles  Hives- allergic reactions to food or medicine  Skin Cancer- excessive exposure to the ultraviolet radiation in sunlight