The skeletal system is the framework for the muscular system to attach to so we can move.

Skeletal System

The skeletal system is the framework for the muscular system to attach to so we can move.

BONE: A rigid connective tissue Helps to move & support the body Protect the organs (skull, ribs) Solid bone: Compact; Stores calcium & phosphorus Spongy bone: Light; adds strength Marrow: Makes red & white blood cells and stores energy (fat) Outer membrane: Holds nerves & blood vessels in canals Capuchin Crypt (Rome, Italy)

Two Major Divisions of the Skeletal System

Axial Skeleton Skull Sternum (breast bone) Ribs Vertebral Column (back bone)

Appendicular Skeleton Pectoral girdle collar bone & shoulder blades Arm bones Pelvic girdle Leg bones

Axial Skeleton - The Skull The skull is the bony framework of the head. It is comprised of 8 cranial bones & 14 facial bones.

Axial Skeleton - The Skull The joints between bones of the skull are immovable (Fixed) and are called sutures. SUTURES

The Skull Major Cranial Bones 1. Frontal

The Skull Major Cranial Bones 2. Parietal

The Skull Major Cranial Bones 3. Temporal

The Skull - Major Cranial Bones 4. Occipital

The Skull Major Cranial Bones 5. Sphenoid

The Skull Major Cranial Bones 6. Ethmoid

Why would a baby s skull have some cartilage instead of a skull made of only bone?

The Skull Major Facial Bones 1. Mandible

The Skull Major Facial Bones 2. Maxillary

The Skull Major Facial Bones 3. Palatine

The Skull Major Facial Bones 4. Zygomatic

The Skull Major Facial Bones 5. Nasal

Skull of a 7 year old child Bones of the upper & lower jaw have been removed to reveal underlying dental structures. Why are there so many teeth?

Axial Skeleton - The Sternum has 3 parts 1 Manubrum 2 The Body 3 Zyphoid Process

The Axial Skeleton The Ribs The first seven pair are called the true ribs. FRONT BACK

The Axial Skeleton The Ribs The next three pair are called false ribs. FRONT BACK

The Axial Skeleton The Ribs The last two sets of are called floating Ribs. FRONT BACK

The Axial Skeleton The Vertebrae The vertebral column (also called the backbone, spine, or spinal column) consists of a series of 33 irregularly shaped bones, called vertebrae. These 33 bones are divided into five categories depending on where they are located in the backbone.

The Axial Skeleton The Cervical Vertebrae The first seven vertebrae are called the cervical vertebrae. They are named C1, C2, C7 starting at the base of the skull and going down the spine. C1 C2 C3 C4 C5 C6 C7

The Axial Skeleton The Cervical Vertebrae The C1 vertebrae is also called the Atlas View of the atlas from the above & below.

The Axial Skeleton The Cervical Vertebrae The C2 vertebrae is called the Axis The atlas and axis differ from all other vertebrae because they are designed primarily for rotation of the head. This forms a Pivot Joint. View of the axis from the above, behind & below.

The Axial Skeleton The Cervical Vertebrae C3 C7 are the remaining bones that make up the neck. Unlike the other regions of the spine, the cervical vertebrae have special openings in each vertebrae for the arteries that carry blood to the brain (#4). View of the atlas from the above.

The Axial Skeleton The Thoracic Vertebrae After the 7 cervical vertebrae are 12 Thoracic vertebrae. The ribs are connected to the thoracic vertebrae. They are T1, T2, T12. T1 is just below C7. View of the thoracic vertebrae from above, and the side.

The Axial Skeleton The Thoracic Vertebrae The ribs connect with the thoracic vertebrae Thoracic Vertebrae Rib Bone

The Axial Skeleton The Lumbar Vertebrae The 5 lumbar vertebrae make up the lower back and do not have ribs attached. L1, L2, L3, L4 & L5

The Axial Skeleton The Sacral Vertebrae There are 5 sacral vertebrae. They are represented by the symbols S1 through S5. The sacral vertebrae are normally fused together to form the sacrum in adults. Anterior View Posterior View S1 S2 S3 S4 S5

The Axial Skeleton The Coccyx or Tailbone The small tail-like bone at the bottom of the spine. The coccyx is made up of 3-5 vertebrae. It is the lowest part of the spinal column.

The Axial Skeleton The Vertebral Discs There are no discs between the Atlas (C1), Axis (C2), and Coccyx. The intervertebral discs make up one fourth of the spinal column's length. NOT SHOWN

The Axial Skeleton The Vertebrae A final look at the vertebral column showing the cervical, thoracic, lumbar and sacral vertebrae. At the very bottom is the coccyx (tailbone).

Pectoral girdle Pelvic girdle Arm & Leg Bones

The Appendicular Skeleton The Pectoral Girdle The bones of the pectoral girdle are the Scapula & Clavicle.

The Appendicular Skeleton The Pectoral Girdle - Scapula The scapula is a large, triangular, flat bone on the back commonly called the shoulder blade. It overlays the 2 nd through 7 th ribs and serves as an attachment for muscles. It has a shallow depression that the head of the arm bone fits into.

The Appendicular Skeleton The Pectoral Girdle - Clavicle The clavicle, commonly called the collar bone, is a slender S-shaped bone that connects the arm to the body and holds the shoulder joint away from the body to allow for greater movement. One end of the clavicle is attached to the sternum & one end to the scapula.

The Appendicular Skeleton The Pelvic Girdle - Female The Pelvic Girdle is composed to 2 hip bones. During childhood, each hip bone consists of 3 separate parts: the ilium (purple), the ischium (red), and the pubis (blue). In an adult, these three bones are firmly fused into a single bone.

The Appendicular Skeleton The Pelvic Girdle - Female In the back, these two hip bones meet on either side of the sacrum. In the front, they are connected by a muscle called the pubic symphysis (green).

The Appendicular Skeleton The Arm & Hand Bones The bones of the human arm extend from the shoulder to the wrist. The humerus is the bone of the upper arm. The rounded head of the humerus fits into a cavity in the scapula (shoulder blade) to form the shoulder joint. The shoulder joint is a ball-and-socket joint that enables full circular movement of the arm.

The Appendicular Skeleton The Arm & Hand Bones Elbow

The Appendicular Skeleton The Arm & Hand Bones The hand is composed of many small bones called carpals, metacarpals and phalanges.

The Appendicular Skeleton The Arm & Hand Bones

The Appendicular Skeleton The Arm & Hand Bones There are 8 carpal bones. The carpal bones are gliding joints. A gliding joint is a joint in which the bony surfaces that the joint holds together are flat, or only slightly round.

The Appendicular Skeleton The Leg & Foot Bones The lower leg is comprised of two bones, the tibia and the smaller fibula. The thigh bone, or femur, is the large upper leg bone that connects the lower leg bones (knee joint) to the pelvic bone (hip joint). http://www.imaios.com/en/e-anatomy/leg-bones-and-arteries

The Appendicular Skeleton The Knee The bones of the knee, the femur and the tibia, meet to form a hinge joint. The joint is protected in front by the patella (kneecap). The knee joint is cushioned by cartilage. Ligaments help to stabilize the knee.

The Appendicular Skeleton The human foot combines mechanical complexity and structural strength. The Foot Bones The ankle serves as foundation, shock absorber, and propulsion engine. The foot can sustain enormous pressure (several tons over the course of a one-mile run) and provides flexibility and resiliency.

The Appendicular Skeleton The Foot Bones

The Appendicular Skeleton Foot Bones vs Hand Bones Tarsals Carpals Metacarpals Metatarsals Phalanges Phalanges

JOINT: the location at where bones meet.

Fixed joint: No movement (immovable) such as skull sutures that form after the skull is fully grown & cartilage is replaced by bone.

Pivot joint: Allows bones to twist against each other such as the neck at the base of the skull so we can turn our head.

Ball & Socket joint: Allows circular, rotational movement such as the hip & shoulder.

Gliding joint: Allows bones to slide against each other such as the wrist & ankle.

Hinge joint: Allows back & forth movement such as elbows, knees, fingers & toes.

Cartilage: Tough, flexible material from which bones form & helps to cushion joints from wear. babies have more cartilage than bone (cartilage later turns into bone) found at ends of long bones, outer ear, & tip of nose

Ligament: Tough band of tissues that connect one bone to another bone.

Tendon: Thick band of connective tissue that attaches muscles to bones so we can move.

Bursa: fluid filled sac between bones that cushions to absorb shock & prevent bones from rubbing against each other.

Sprain: forcible twisting of a joint Arthritis: inflammation of the joints caused by infection, aging, or injury One type of arthritis results in breakdown of cartilage at the joints. How would this affect a person s life? It causes pain and swelling; in time the person may not be able to bend or move the affected part of the body What can be done to help people whose joints are severely affected by arthritis? Diseased joints can be replaced with plastic or metal ones What can happen to bones if a person doesn t get enough calcium in their diet? Bones can become brittle and break easily

Fracture: A broken bone Osteoporosis: A loss of bone mass due to a lack of calcium in the diet weakening the bones Rickets: A vitamin D deficiency that softens the bone

Dog Skeleton

Cat Skeleton

Sabertooth Tiger Skeleton

Rat Skeleton

Aquatic Dinosaur Skeleton

Bat Skeleton

Elephant Skeleton

Pig Skeleton

Alligator Skeleton

Blue Whale Skeleton

Sea Lion Skeleton