Chapter 6 Flashcards
Skeletal system includes what 4 things?
Bones.
Cartilages.
Ligaments.
Connective Tissue.
Six Functions of the skeletal system?
Support. Storage of Minerals (calcium). Storage of Lipids (yellow marrow). Blood cell production (red marrow). Protection. Leverage (force of motion).
Where’s calcium stored in the body?
The Skeletal System.
3 properties that bones are identified by?
Shape.
Internal Tissues.
Bone Markings.
5 types of bone shapes.
Long Bones. Flat Bones. Irregular Bones. Short Bones. Sesamoid Bones.
4 types of long bones?
Humerus.
Femur.
Tibula.
Fibia.
Where do Sesamoid Bones develop?
Inside tendons near joints of knees, hands, and feet.
These bones are small and flat.
Sesamoid bones.
This part of the long bones connects the epiphysis to the disphysis. Generally the neck of the long bone.
Metaphysis.
Epiphysis is what part of the long bone?
The wide part at the end.
Articulation with other bones.
Diaphysis is what part of the long bone?
The shaft of the long bone.
Bone is 2/3 ___________ and 1/3 __________(collagen).
Calcium Phosphate.
Protein Fibers.
What percent of bone mass does bone make up?
2%
Three types of bone cells.
Osteocytes.
Osteoblasts.
Osteoclasts.
2 main functions of Osteocytes.
Provide nutrients to living bone.
Help repair damaged bone.
Mature bone cells that maintain the bone matrix.
Osteocytes.
Immature bone cells that secrete matrix compounds. What’s this process called?
Osteoblasts.
Osteogenesis.
Osteoid,
Matrix produced by osteoblasts but not yet calcified to form bone.
Osteoblasts surrounded by bone become _______.
Osteocytes are what they become.
Giant, multinucleate cells that dissolve bone matrix and release stored minerals.
Osteoclasts.
Osteolysis.
Dissolve bone matrix. Stored minerals (calcium) are released as a result.
Secrete acids and protein-digesting enzymes.
Osteoclasts.
Two bones cells involved in bone building.
Osteocytes and osteoblasts.
Bone cell(s) involved in bone building.
Osteocytes and Osteoblasts.
Bone cell(s) involved in bone recycling.
Osteoclasts.
What can help osteocytes build bone?
Weight barring exercise.
R: (What can this help do for bone?)
Compact bone is defined by _______.
Osteons.
R: (Define what type of bone?)
What wraps Osteons?
Circumferential lamellae.
R: (What do these wrap)
Which bone makes up a larger percentage of the skeleton?
Compact bone.
The basic unit of mature compact bone.
Osteon.
Osteocytes are arranged in ___________.
Concentric lamellae.
R: What arranges in these?
Blood vessels run through the __________ surrounded by concentric lamellae.
Central canal.
What runs through the central canal?
Blood vessels.
R: Run through what in compact bone?
Spongy bone does not have _______.
Osteons.
The matrix in spongy bone forms a bundle of fibers called _______.
Trabeculae.
Which bone is found in areas that are not heavily stressed?
Spongy bone.
Found in spongy bone, doesn’t contain blood vessels.
Trabeculae.
Present in the space between trabeculae. Forms red blood cells, and supplies nutrient to osteocytes.
Red bone marrow.
R: Where? what do they do?
In some bones, spongy bone holds _______, which stores fat.
Yellow Marrow.
R: Where? What do they do?
Two coverings of bone include ________ on the outside, and _______ on the inside.
Periosteum.
Endosteum.
R: What are these? Where are they?
What do both periosteum and endosteum do?
Heal damaged bone.
R: Two types of bone coverings that do this.
Periosteum has a _____ outer layer and a _______ inner layer.
Fibrous.
Cellular.
Three effects the periosteum provides.
Isolates bone from surrounding tissue.
Provides a route for the blood vessels and nerves.
Takes part in bone growth and repair.
An incomplete cellular layer of bone covering.
Endosteum.
Four properties and effects of the endosteum.
Lines the marrow cavity.
Covers trabeculae of spongy bone.
Lines central canals.
Active in bone growth and repair.
Three cells present in endosteum.
Osteoblasts.
Osteoprogenitor.
Osteoclasts.
Osteogenesis?
Bone Formation.
Ossification?
The Process of replacing other tissues with bone.
What age do you human bones grow till?
age 25.
If deposition is greater than removal, bones get _____.
Stronger.
If removal is faster than replacement, bones get _______.
Weaker.
Mineral recycling allows bones to adapt to _____.
Stress
How much bone mass can be lost in a few weeks of inactivity?
Up to 1/3 of bone mass.
Two important minerals for bone.
Calcium and Phosphate salts.
4 Vitamins important for bone.
Vitamin C.
Vitamin A.
Vitamin K.
Vitamin B12.
Vitamin C role in bone.
Required for collagen synthesis, and stimulates osteoblast differentiation.
Vitamin A role in bone.
Stimulates osteoblast activity.
Vitamin K and B12 role in bone.
Helps synthesize bone proteins.
What two hormones stimulate bone growth?
Growth Hormone .
Thyroxine.
What two hormones stimulate osteoblasts?
Estrogen.
Androgen.
What two hormones regulate calcium and phosphate levels?
Calcitonin.
Parathyroid Hormone.
The most abundant mineral in the body?
Calcium.
Bones store _______ and other _______
Calcium.
minerals.
Calcium ions are vital to what three things?
Membranes.
Neurons.
Muscles cells (especially heart cells) .
Two hormones that maintain calcium level homeostasis.
Calcitonin.
Parathyroid Hormone.
Where is Calcium Absorbed?
The Digestive Tract.
Where is calcium excreted?
The Kidneys.
Where is Parathyroid Hormone produced?
The Parathyroid Glands.
What’s the function of the Parathyroid Hormone?
To increase Blood Calcium Ion levels.
What hormone is released when the body has low blood calcium ion levels?
Parathyroid Hormone.
How does PTH increase calcium ion levels?
Stimulates osteoclasts.
Increases intestinal absorption of calcium.
Decreases calcium excretion at kidneys.
What’s the “opposite” of PTH?
Calcitonin .
Calcitonin function?
Decrease blood calcium ion levels.
What secretes Calcitonin?
C cells (Parafollicular cells) in thyroid.
How does calcitonin decrease blood calcium ion levels?
inhibiting osteoclast activity.
increasing calcium excretion at kidneys.
Difference between a “Sign” and a “Symptom”
A sign is objective.
A symptom is subjective.
Primary way to obtain calcium ions?
Diet.
______ and phosphate ions in blood are lost in urine.
Calcium.
What happens if calcium ions are not obtained from diet?
Weakens bones, causing Osteoporosis.
Two things that keep bones strong.
Exercise and nutrition.
With regard to bones, what begins between ages 30 and 40?
Osteopenia.
What’s Osteopenia?
A precursor to osteoporosis. When bone density is lower than normal.
Women lose __% of bone mass per decade, men ___%.
8.
3.
What’s osteoporosis? Over age 45, occurs in what percent of women and men?
Severe bone loss.
29% women.
18% men.
What two hormones help maintain bone mass?
Estrogens and Androgens.
Bone loss in women accelerates after __________.
Menopause.
Cancerous tissue can stimulate osteoclast activation, causing……
Severe osteoporosis.
