Distinguish between the functions of red marrow and yellow marrow. Sponge: Set up Cornell Notes on pg. 57 Topic: 7.1 Functions of bone Essential Question: Distinguish between the functions of red marrow and yellow marrow. 7.1 Bone Function 2.1 Atoms, Ions, and Molecules Distinguish between the functions of red marrow and yellow marrow.

Skeletal System Bones may appear to be non-living, but bone contains very active, living tissues Bone tissue Cartilage Dense connective tissue Blood Nervous tissue

On p. 57 Tree Map of functions of bone Skeletal System: Functions of Bone Support Protection Movement Blood cell formation Inorganic Salt Storage

Support/Framework Give shape to head, face, thorax (chest), and limbs Bones of lower limbs, pelvis, and vertebral column support the body’s weight

Protection Skull protects eyes, ears, and brain Ribs cage protects heart and lungs Pelvic girdle protects reproductive organs

Movement Provide points of attachment for muscles

Blood cell formation Hematopoiesis (he-mă-tō-poi-ē-sis): process of blood cell formation that occurs in the bone marrow Red marrow: forms RBC, WBC, and platelets Yellow marrow: stores fat and is inactive in blood cell production In cases of severe blood loss, the body can convert yellow marrow back to red marrow to increase blood cell production.

Inorganic Salt Storage The salts account for 70% of the extracellular matrix of bone tissue by weight Body requires calcium for blood clot formation Osteoporosis- loss of bone mass and mineral content Bones develop spaces and canals Enlarge and fill with fatty tissue No longer able to support body weight Easily fracture Associated with aging

Clinical Application 7.1 Classwork/Homework Read Clinical App 7.1 on fractures Answer and HIGHLIGHT the answers in your reading as a way to cite your evidence

Body Story: Breaking Down 1m28-24m45s

GET OUT CLINICAL APP. HW FROM YESTERDAY Sponge: Set up Cornell Notes on pg. 59 Topic: 7.1 Bone Classification Essential Question: What is the major difference between osteoblasts and osteoclasts? 7.1 Bone Classification 2.1 Atoms, Ions, and Molecules What is the major difference between osteoblasts and osteoclasts? GET OUT CLINICAL APP. HW FROM YESTERDAY

Bone Classification Sheet Send someone up for your bone classification sheet Make sure you include a description of the parts Include examples of bones

Bone Structure: Bone Classification Bones are classified according to their shapes: A. Long bones have long longitudinal axes and expanded ends. Ex: the femur B. Short bones are cube-like, lengths and widths roughly equal Ex: wrist and ankle bones

C. Flat bones are plate-like structures with broad surfaces. Ex: the ribs, scapulae, and some bones of the skull D. Irregular bones have a variety of shapes. Ex: the vertebrae and many facial bones

E. Round (sesamoid) bones These bones are small and nodular and imbedded within tendons adjacent to joints. Ex: The patella

Structure v. Function A bone’s shape makes its functions possible: Bony projections called processes, provide sites for attachments of ligaments and tendons Grooves and openings are passageways for blood vessels and nerves A depression in one bone might articulate with the process of another.

Parts of a Long Bone (Back of handout) Make sure you label AND give a description of the parts and/or function

Please add Label your long bone

Bone Structure: Parts of a long bone Epiphysis (ĕ-pif-ĭ-sees)- an expanded portion of bone found at the end of a long bone Forms a joint with another bone Red bone marrow found here Diaphysis (dī-af’-ĭ-sis)- the shaft of the bone Yellow bone marrow found here

Periosteum (per-ē-os-te-um)- a tough, vascular covering of fibrous tissue Firmly attached to bone Help form and repair bone tissue

Spongy bone- Filled with spaces reduces the weight of bone Spaces contain red marrow Found in the epiphyses Strong and resistant to bending Cells NOT collected near a central canal

Trabeculae (trah-bek-ū-le) the many branching bony plates within the spongy bone

Canaliculi (can-ă-lic-ū-lī) Small channels where nutritional substances diffuse to the bone cells lead to the surface of the trabeculae

Spongy bone (w/ marrow)- microscopic Red Marrow Spongy bone

Bone Structure Compact bone- Tightly packed bone tissue with no gaps Found in the wall of the diaphysis and in thin layers above spongy bone Strong and resistant to bending

Compact bone is made of osteons cemented together by bone matrix Osteons-Cylinder-shaped unit containing osteocytes that surround a central canal Osteocytes- bone cells

Central Canal- contains blood vessels and nerve fibers Ensures that every bone is close to a nutrient supply

Medullary cavity- hollow chamber in a semi-rigid tube within compact bone Continuous with the spaces of the spongy bone Endosteum thin layer of tissue that lines the Medullary cavity which contain bone-forming cells Marrow- filled with yellow marrow

Compact bone- microscope

P. 59 Bone Formation Osteoblasts: “Bone formers” cells Will eventually become osteocytes Osteoclasts: “Bone destroyers” Resorb bone material

Bone Remodeling Bone remodeling: Osteoclasts destroy bone tissue, while osteoblasts replace tissue Important so that total mass of bone remains constant Completely new skeleton about every 10 years! Slows as we age i.e. osteoporosis

Fun Fact!!! Astronauts experience a one percent loss of bone mass per month in space Under microgravity conditions: Osteoclast activity increases Osteoblast activity decreases Greater loss of spongy bone than compact bone Astronauts could have 50% bone loss occurrence on a several-year long space flight

Bone Growth and Development The skeleton starts forming during the first two weeks of prenatal development, and bones continue to grow into adulthood.

Bone Growth and Development Bones form by replacing connective tissue in one of two ways: 1. Intramembranous bones originate within sheet-like layers of connective tissues. Ex: Skull bones, clavicle, and mandible are intramembranous bones

Bone Growth and Development 2. Endochondral bones begin as masses of cartilage that are later replaced by bone tissue. Most of your bones are endochondral Ossification- formation of cartilage into bone

Skeletal Function and Classification 30s-3m

P. 58 Clinical Application 7.2 Classwork/Homework Read Clinical App 7.2 on Osteoporosis Answer and HIGHLIGHT the answers in your reading as a way to cite your evidence Read/highlight article on back