Chapter 7 Lesson 7.1

Skeletal system 206 bones make up the skeletal systemFunctions1. Supports and protects2. Makes red and white blood

cells3. Stores minerals like

calcium and phosphorus4. Aid in movement, muscles

attach to bones

MUSCULAR SYSTEMFUNCTION - MOVEMENT

MORE THAN 650 MUSCLES IN THE BODY

Two categories: VOLUNTARY AND INVOLUNTARY

MUSCLES ALSO RESPONSIBLE FOR THE HEART BEATING AND YOU BREATHING

SKELETAL SYSTEMTwo broad divisions:

1. Axial skeleton•trunk of the body •Includes

a. vertebral columnb. skullc. thoracic cage (ribs, sternum, and vertebrae),d. hyoid bone (in the neck)

SKELETAL SYSTEMTwo broad divisions:

1. Axial skeleton

2. Appendicular skeleton – the appendages and their girdles (where they attach to the axial skeleton).

Axial skeletonSkull – Cranial bones divided into two main parts:

1. CRANIUM LARGEST PART OF THE SKULL IS MADE OF THE CRANIAL BONES HAS 8 BONES THAT ARE JOINEDINCLUDES BONES OF THE BACK OF HEAD, SIDE, AND TOP

Axial skeleton

Skull – Cranial bones divided into two main parts:1. CRANIUM

2. FACIAL

14 BONESFACE AND JAW

Bones of the Cranium

Parietal

Occipital

Temporal

Sutures - in adults where the bones of cranium are joined tightly together which will absorb shock.

Frontanels – tough membrane in babies/children where the bones of cranium are connected which allows a baby’s brain to grow.

Facial Bones

Frontal

Maxilla

MaxillaMakes up central portion of faceWhere upper teeth are attached

Mandible

Mandible•Lower jaw•Lower teeth attach•Moves •Held to skull by ligaments

•Ligaments are connective tissue that hold bones to bones

Palate – roof of mouth formed by palatine bones and maxillary bones

Palatine boneMaxilla

Sinuses – air-filled pockets (hollow spaces in the bone) located within the bones of the face and around the nasal cavity.

Function:Sound resonation

Makes skull lighter

Hyoid bone – in the upper neck and where muscles like tongue attach.

Smallest bones of body in the ear and include:

Malleus (hammer)Incus (anvil)Stapes(stirrup)

Function: to amplify

the sound

Vertebral Column

Function: to protect the spinal cord and supportthe body.

Composed of 26 vertebraeor individual bones.

Types of Vertebrae:•7 cervical (head attaches)•12 thoracic (ribs attach)•5 lumbar (support weight)•5 fused sacral – five fused vertebrae• 4 fused coccyx also called the tailbone

C1: To blood supply to the head, pituitary gland, scalp, bones of the face, brain inner and middle ear, sympathetic nervous system, eyes, ears C2: To eyes, optic nerves, auditory nerves, sinuses, mastoid bones, tongue, forehead, heart C3: To cheeks, outer ear, face, bones, teeth, trifacial nerve, lungs C4: To nose, lips, mouth, Eustachian tube, mucus membranes, lungs C5: To vocal cords, neck glands, pharynx C6: To neck muscles, shoulders, tonsils C7: Tothyroid gland, bursa in the shoulders, elbows T1: To arms from the elbows down, including hands, arms, wrists and fingers; esophagus and trachea, heart T2: To heart, including its valves and covering coronary arteries; lungs bronchial tubes T3: To lungs, bronchial tubes, pleura, chest, breast, heart T4: To gallbladder, common duct, heart, lungs, bronchial tubes T5: To liver, solar plexus, circulation (general), heart, esophagus, stomach T6: To stomach, esophagus, peritoneum, liver, duodenum T7: To kidneys, appendix, testes, ovaries, uterus, adrenal cortex, spleen, pancreas, large intestine T8: To spleen, stomach, liver, pancreas, gallbladder, adrenal cortex, small intestine, pyloric valve T9: To adrenal cortex, pancreas, spleen, gallbladder, ovaries, uterus, small intestine T10: To kidneys, appendix, testes, ovaries, uterus, adrenal cortex, spleen, pancreas, large intestine T11: To kidneys, ureters, large intestine, urinary bladder, adrenal medulla, adrenal cortex, uterus, ovaries, ileocecal valve T12: To small intestine, lymph circulation, large intestine, urinary bladder, uterus, kdneys, ileocecal valve L1: To large intesine, inguinal rings, uterus L2: To appendix, abdomen, upper leg, urinary bladder L3: To sex organs, uterus, bladder, knee, prostate, large intestine L4: To prostate gland, muscles of the lower back, sciatic nerve L5: To lower legs, ankles, feet, prostate Sacrum: To hip bones, buttocks, rectum, sex organs, genitalia, urinary bladder, ureter, prostate Sacral Plexus: Forms the sciatic as well as other nerves that go to muscles, joints and other structures of the legs, knees, ankles, feet and toes Coccyx: To rectum, anus

Spinal curvature:

Spine is “S” shaped with 4 curvatures:cervical – convex (forward)thoracic – concave (back)lumbar – convex (forward)sacral – concave (back)

Curved spine acts as a shock absorber, and for strength and flexibility.

Vertebral column is made up of vertebrae stacked upon each other.

•Between the vertebrae are the intervertebral disc made up of cartilage.

•Cartilage – tough, rubbery connective tissue.

•Disk act as shock absorbers.

Atlas and axis – first two cervical vertebrae that support head and allow for sideways movement.

Abnormalities of the curvature of the spine:Scoliosis – abnormal sideways curve of the spine.Kyphosis – (hunchback) abnormal curve of the thoracic vertebraeLordosis – (swayback) abnormal curve of the lumbar vertebrae

Thoracic cage:

Function: protects organs such as the heart and lungs

Includes:ribs and sternum

RibsAttach to the thoracic vertebrae in back and most attach to the sternum in the front by costal cartilageThere are 12 pairs for both male and female, but one of best areas for regenerating

Types of Ribs:•True ribs – first seven pairs that connect to sternum directly by costal cartilage.•False ribs – last five pair that indirectly attach by joining the cartilage of the 7th rib or don’t attach to the sternum at all.

Types of Ribs:•True ribs•False ribe

•Floating ribs – last two pairs of false ribs that do not attach to sternum directly or indirectly.