The Skeletal System Unit-Anatomy and Physiology Part I

What you will Learn! The functions of the skeleton Describe the general structure of a bone and list the functions of its parts List and define the major kinds of bones in the human skeleton Name and describe the general types of fractures Distinguish between the axial and appendicular skeletons and name the major parts of each Locate and identify the bones and the major features of the bones that comprise the skull, arms, legs, pectoral and pelvic girdles

What Does Your Skeleton Do? Five Functions: Protects your internal organs Supports-provides a framework so that we can stand up and move Movement-many of the body muscles attach to the skeleton and joints and produce movement Stores minerals such as calcium, potassium, phosphorus, and sodium so that our body can function properly Produces blood cells

The Skeletal System The Skeletal System is made up of 206 different bones. There are 4 basic shapes of bones.

4 Basic Shapes 1. Long bones- Are longer than they are wide and are found in the upper limbs such as the humerus (arm) and lower limbs such as the femur (thigh).

4 Basic Shapes 2. Short bones- Such as those found in the wrist and ankle bones.

4 Basic Shapes 3. Flat bones- Such as the scapula, ribs and sternum, and the thin bones that form the roof of the skull.

4 Basic Shapes 4. Irregular bones- Such as the vertebrae, pelvic girdle (hip bones), and parts of the skull bones such as your ear bones.

2 Types of Bone Tissue Compact Bone- Dense Smooth Strong Both Compact and Cancellous bone tissue contain living cells which help make repairs if a bone is injured or broken. Cancellous Bone- Spongy Lightweight

Structure of the Bone 1.Diaphysis -the bone shaft Composed of compact bone tissue-tightly packed together tissue that is solid, strong and will not bend. Inside the bone shaft is a cavity called the Medullary Cavity (also called yellow marrow) that stores fat, produces blood cells and plays an important part in our immune system.

Structure of the Bone 2. Epiphysis-the two ends of the shaft Spongy bone-contains the red marrow that functions in the formation of red blood cells, certain white blood cells and platelets. It is red because of the red, oxygen-carrying pigment called hemoglobin. 3. Periosteum-a tough, vascular covering of fibrous tissue that covers the bone.

The Skeletal System Part II The Axial and Appendicular Skeleton Unit-Anatomy and Physiology Part II

2 Divisions of the Skeletal System Axial Skeleton Appendicular Skeleton

The Appendicular Skeleton Appendicular Skeleton Has 126 bones Contains upper extremities Shoulders Lower extremities Hips (Pelvic Girdle)

Upper Extremities and Shoulder Upper Extremities (Arms): humerus-the bone that extends from the scapula to the elbow radius—the bone that extends from the elbow to the wrist ulna-the bone that overlaps the end of the humerus posteriorly Shoulder girdle: Scapula-shoulder blade Clavicles-collar bone

The Hands 27 bones carpal bones-8 on each arm make up the wrist metacarpal bones-5 on each hand make of the palm phalanges-3 in each finger, 2 in the thumb, a total of 14 in each hand

Lower Extremities and Hips Lower Extremities-(Legs) femur- thigh bone patella- kneecap tibia-shinbone fibula-lateral side of the tibia Hips (Pelvic Girdle)-protect the bladder, the reproductive organs, lower colon and rectum. os coxa--2 bones that make up the hip ilium--largest and uppermost portion ischium-lowest portion and is L-shaped; supports ones weight when seated pubis--the anterior portion

The Foot 26 bones and 33 joints tarsals--7 bones in each foot; make up the ankle that includes the calcaneus (heel bone) which is the largest of the ankle bones metatarsals--5 bones on each foot phalanges—3 bones in each toe, except the big toe which has only =26

The Axial Skeleton Has 80 bones Consist of: Bones of the Skull Hyoid Bone (neck bone) The vertebral column The thorax (cage)

Bones of the Skull-Cranial Bones Cranial Bones: A. Frontal Bone--forms the anterior portion of the skull above the eyes B. Parietal Bone--2 bones on each side of the skull just posterior to the frontal bone C. Occipital Bone--back of the skull and base of the cranium D. Temporal Bone—2 bones on each side of the skull E. Sphenoid Bone--anterior to temporal F. Ethmoid Bone--located in front of the sphenoid Cranial Sutures-lines that join two bones

Skull-Ear Bones 3 Middle ear bones- ossicles malleus-hammer stapes-stirrup (smallest bone in the body) incus-anvil

Skull – Facial Bones 13 immovable ones and 1 immovable lower jawbones maxilla--2 bones of upper jaw palatine--2 bones behind the maxilla; make up posterior portion of the hard palate zygomatic--2 bones that make up the cheeks lacrimal--2 bones in the medial wall of each orbit nasal--2 bones that fuse to form the bridge of the nose vomer--a single bone in the middle of the nasal cavity inferior nasal concha--2 fragile, scroll-shaped bones attached to the nasal cavity mandible--1 lower jawbone (only part that moves when you eat and talk)

Hyoid Bone Hyoid bone--located in the neck between the lower jaw and the larynx serves as an attachment for muscles that help move the tongue and for swallowing

The Vertebral Column Supports the body's frame, keeping it standing upright. It connects the head to the rest of the body Serves as protection for the spinal cord Bones: cervical--7 bones thoracic--12 bones lumbar--5 bones sacrum--1 bone; composed of 5 fused bones coccyx--1 bone; tailbone composed of 4 fused vertebrae

The Thorax Thoracic Cage-protects the heart and lungs 1. ribs--12 pair (24 ribs) a. true ribs--first 7 pair; directly join the sternum b. false ribs--remaining 5 pair because their cartilage does not reach the sternum directly c. floating ribs--last 2 pair of the 5 pair of false ribs; called floating because they have no attachments 2. sternum--1 breastbone

The End!