1. Bones, Muscles and Skin

2. Section 1  Body Organization and Homeostasis

3. Body Organization and Homeostasis  The levels or organization in the human body consist of cells, tissues, organs and organ systems  Cells is the most basic organized part of the body  System is the most advanced

4. Cells  Cell is the basic unit of structure and function in a living thing  Human body contains about 100 trillion cells  Cell membrane forms on the boundary of the cell  The nucleus is the control center that directs the cells activities  The material within a cell is the cytoplasm, it is clear and jelly-like

5. Cells  Inside the cytoplasm are structures called organelles  Cells carry on the processes that keep the organism alive  Cells grow and reproduce  They rid the organism of waste and helps break down food to release energy

7. Tissues  Tissue is a group of similar cells that perform the same function  Muscular tissue can shorten and contract  Nervous tissue directs and controls the body using electrical messages  Connective tissue provides support and connects all its parts  Epithelial tissue covers you body inside and out

9. Organ and Organ Systems  Organ is a structure that is composed of different kinds of tissue  Organs perform a specific job like a tissue, but is more complex than a tissue  An organ system is a group of organs that work together to perform a major function

11. Homeostasis  The different organ systems work together and depend on one another  All the systems of the body work together to maintain homeostasis, to keep the internal balance  Homeostasis is the process by which an organism’s internal environment is kept stable in spite of changes in the external environment

12. Homeostasis  Very simply even when its cold out, your body will always have the same temp.  Body temp. will drop when you are sick  Your body has various ways to maintain homeostasis  When it is warm out, you sweat to help cool off your body  When it is cold, your body shivers, the shivering helps to provide heat for your body

13. Section 2  The Skeletal System

14. What the Skeletal System Does  Our skeleton is our framework  It is made up of all the bones in our body  The number of bones in your body depends on how old you are.  A newborn has 275 bones  An adult has 206 bones  As babies grow, bones in the body fuse together.

15. What the Skeletal System Does  Your skeleton has 5 major functions  Provides support and shape for the body  Enables you to move  Protects your organs  Produces blood cells  Stores minerals and other materials until your body needs them

16. What the Skeletal System Does  The backbone, or vertebral column, is the center of the skeleton.  If you run your fingers down the length of your back you will feel 26 vertebrae  Most of the bones in your body are associated with muscles  Bones also protect vital organs  Bones also produce certain blood cells, and store other vitamins and minerals.

18. Joints of the Skeleton  A joint is a place in the body where 2 bones come together  Joints allow bones to move in different ways  There are 2 different types of joints, moveable and immoveable.  Immovable are joints that allow for little or no movement  The bones in the skull are held together by immovable joints

19. Joints of the Skeleton  Most of the joints in the body are moveable joints.  Moveable joints allow for a wide range of motion  The joints in the body are held together by strong connective tissues called ligaments  Most joints have a second connective tissue called cartilage, which is more flexible than bone

20. Joints of the Skeleton  Cartilage covers the ends of the bones and keeps them from rubbing together  There is also a fluid that helps to lubricate the ends of the bones

22. Bones- Strong and Living  The word skeleton comes from a Greek word meaning “a dried body”  Bones are actually complex living structures that undergo growth and development  The longest bone in your body is your Femur, it is also the toughest to break.  Blood vessels and nerves enter and leave the bone through the membrane.

24. Bones- Strong and Living  Beneath the bone’s outer membrane is a layer of compact bone, which is hard and dense, but not solid.  These small canals carry blood vessels and nerves from the bone’s surface to the living cells within bone.  Spongy bone has many small spaces within it  This structure makes spongy bone tissue lightweight.

25. Bones- Strong and Living  Inside many bones contain a soft, connective tissue called marrow.  There are 2 types of marrow, red and yellow  Red bone marrow produces most of the body’s red blood cells.  As a child most of your marrow is red, as a teenager, only the ends of femurs, skull, hip bones, and sternum  Yellow marrow stores fat as an energy reserve

26. Bones- Strong and Living  Bones are strong and lightweight, stronger than concrete or granite rock.  Only 20% of an adults weight is bone  Even when you get old, your bone tissue will continue to grow  So even when you break a bone, new bone tissue forms and the healed region will be stronger than before.  Bones develop from cartilage into bone, but not everywhere

27. Taking Care of Your Bones  A combination of a balanced diet and regular exercise are important for a lifetime of healthy bones  A healthy diet has calcium and phosphorus  Meats, whole grains, leafy vegetables, and dairy products.  We try to prevent against osteoporosis  Condition in which the body’s bones become weak and break easy.

29. Section 3  Diagnosing Bone and Joint Injuries

30. Common Skeletal System Injuries  3 common skeletal system injuries are fractures, dislocations, and sprains.  A fracture is a break in the bone.  Simple=> cracked or completely broken in 2 or more pieces.  Compound=> the bone is sticking out of the skin  Dislocation occurs when the end of a bone comes out of its socket  Sprain is when ligaments stretch to far

31. Identifying Injuries  There are 2 ways to identify injuries of the skeletal system, X-rays and MRI  X-rays are a form of energy that travels in waves  A lead apron is used to protect from unnecessary exposure  The X-rays pass thru soft tissue but not the bones  One limitation is that it can not be used to observe soft tissue damage

32. Identifying Injuries  An MRI, magnetic resonance imaging, is a large machine that contains magnets  The subject is exposed to short bursts of magnetic energy  This causes atoms in the body to vibrate or resonate.  A computer then analyzes the vibration patterns.

33. Treating Injuries  In addition to wearing a cast, 2 other ways to treat skeletal system injuries include surgical procedures such as joint replacement and arthroscopy  Joint replacement usually happens to people with arthritis, a disease of the joints.

35. Treating Injuries  Arthroscopic surgery  Doctors make a small incision and insert a slim, tube shaped instrument called an arthroscope.  Attached to the arthroscope is a small camera that is connected to a small monitor.  Once the problem area is found, doctors make another incision and use small instruments to make necessary repairs.

36. Section 4  The Muscular System

37. Types of Muscles  There are about 600 muscles in the human body.  Some muscles are easy to control, others are impossible to control  The beating of your heart and breathing are muscles you are unable to control, these are called involuntary muscles.

38. Types of Muscle  There are 3 types of muscle tissue  Skeletal muscle  Smooth muscle  Cardiac Muscle  Some are voluntary, some are involuntary

40. Types of Muscles  Skeletal muscles are attached to the bones of your skeleton and provide the force that moves your bones  Skeletal muscle is striated, meaning its in badns and gets tired  At the end of a skeletal muscle is a tendon  A tendon is a strong connective tissue that attaches muscle to bone  Because you are able to control the muscles in your arms and legs, they are a voluntary muscle

41. Types of Muscles  Smooth muscle are inside many internal organs such as the stomach and blood vessels.  Since you can not control your stomach, these muscles are involuntary  Smooth muscles tire more slowly than skeletal muscle

42. Types of Muscle  Cardiac muscle is found only in your heart  Cardiac muscle has some characteristics with both smooth and skeletal muscle  Cardiac muscle never gets tired like skeletal muscle, but is striated.  It is also involuntary

43. Muscles at Work  Because muscle cells can only contract, not extend, skeletal muscles must work in pairs.  While one muscle contracts, the other muscle in the pair relaxes to its original length.

44. Section 5  The Skin

45. The Body’s Tough Covering  The skin protects the body from injury, infection, and water loss.  The skin also helps regulate body temperature, eliminate wastes, gather info. About the envir., and produce vitamin D.

46. The Epidermis  The skin is organized into 2 main layers, the epidermis and dermis.  The epidermis is the outer layer of the skin  Epidermis is usually thinner than the dermis  The epidermis does not have any blood vessel or nerves  This is why shallow scratches do not bleed or hurt

47. The Epidermis  Epidermal cells have a life cycle  The skin cells we see, and come off as dead skin cells, were once living when at the bottom of the epidermal layer

49. The Epidermis  In some ways, the cells of the epidermis are more valuable dead than alive.  Most protection is due to the layer of dead cells on the surface  Shedding of dead skin cells carries away bacteria and other substances on your skin.  Skin also produces melanin, a pigment, or colored substance that gives skin its color

50. The Dermis  The dermis is the inner layer of the skin.  The dermis is about a layer of fat but beneath the epidermal layer.  The fat layer helps to pad the internal organs and helps keep heat in the body.  The dermis is the layer of skin that has nerves, blood cells, sweat glands, hairs and oil glands.

51. The Dermis  Sweat glands produce perspiration which reach the surface through pores.  Strands of hair grow within the dermis in structures called follicles  The hair you see about the epidermal layer is made up of dead cells

52. Caring for your Skin  3 simple habits can help you keep your skin healthy  Eat a healthy diet  Keep your skin clean and dry  Limit your exposure to the sun

53.  The End