A&P test 2- chapter 6

the _________ is the end of a long bone

epiphysis

list the 3 hormones in play in calcium homeostasis

-PTH -calcitonin -calcitriol (activated vitamin d)

which body systems are involved in maintaining homeostatic levels of calcium in he body?

-digestive -endocrine -skeletal -renal

the bone matrix consists of ____________ acid, __________ sulfate, collagen fibers and water

-hyaluronic acid -chondroitin sulfate

what is the name of the growth process that occurs at the epiphyseal plates and how does it allow long bones to grow?

-interstitual growth -bones grow in length

________ resorb old bone that lines the medullary cavity while ______ produce new bone tissue beneath the periosteum

-osteoclasts -osteoblasts

when circulating levels of calcium are inadequate, the cells release __________ which stimulates ________ proliferation and resorption of bone

-parathyroid hormone -osteoclast

the 4 major steps of the mechanism of bone repair

1. formation of hematoma 2. formation of a fibrocartilage callus 3. formation of a bony callus 4. bone remodeling

primary ossification centers begin by?

12 weeks

the fibrous cartilage in between bones of the skull is replaced by bone by ______ years old

2 years old

the _________ canals are at the center of and perpendicular to osteons and carry blood vessels and nerves

Haversian canal

____________ may cause bone loss, cardiac arrhythmias or failure, decreased blood clotting, and decreased nerve function

Hypocalcemia

which zone of growth is where lipids, glycogen, and alkaline phosphatase accumulate; matrix calcifies

Maturization and hypertrophy zone

which cell type derive from the hematopoietic stem cells?

Osteoclast

bone disease due to poor mineralization

Osteomalacia (soft bones)

bone disease due to excessive bone deposit and remodeling

Paget's disease

a bone disease due to poor mineralization in children

Rickets

____________ will stimulate production of vitamin D in the integumentary system

UV rays (sunlight)

at what age are all bones completely ossified and skeletal growth ceases?

age 25

what happens when there is a lack of vitamin D in the body?

a vitamin D deficiency causes the bones to become soft and bend. In children, this leads to rickets. In adults this leads to osteomalacia. Causing weak bones, bone pain, and muscle weakness.

_________causes our body proportions to change between infancy and adulthood

allometric growth

what is the differential growth of body parts?

allometric growth

after a fracture has healed, a bump is often palpable under the skin. This dumb would be a ____________ ____________

an external callus

____________is when bones are increasing in length and also increasing in diameter; growth in diameter can continue even after longitudinal growth ceases.

appositional

____________ means that the cartilage has no blood vessels supplying nutrients and removing metabolic wastes

avascular

unlike most connective tissues, cartilage is ___________

avascular

what characteristics cause cartilage to differ from bone?

bone has a good blood supply and cartilage tissue does not

What does PTH target?

bone matrix

the bone framework is a flexible, semi solid matrix produced by ________

chondroblasts

___________ are cartilage cells

chondrocytes

the ________ form by intramembranous ossification

clavicle

a fracture in which the skin remains intact

closed fracture

what does calcitonin target?

bones and kidneys

which bones form via endochondral ossification?

bones at the base of the skull and long bones

the name "membrane bones" is the name given to which type of bones?

bones that are initially formed by intramembranous ossification

the skeletal system includes:

bones, joints, and cartilage

most long bones begin ossifying when?

by 8 weeks

what is calcium homeostasis?

calcemia- levels of calcium in the blood

the zone of bone growth where cell death occurs

calcified matrix

_____________ will decrease plasma levels of calcium by increasing osteoblast activity, decreasing osteoclast activity, and by blocking calcium re-absorption at the kidneys.

calcitonin

inhibits osteoclast activity and stimulates calcium uptake by bones

calcitonin

stimulates absorption of calcium and phosphate from digestive tract

calcitriol

________ is critical for nerve impulse transmission, and muscle contraction, blood clotting, secretion by glands and nerve cells, cell division, fertilization

calcium

growth hormone goes with _______

calcium retention

chondrocytes from the endosteum create and internal _______by secreting fibrocartilaginous matrix between the two ends of broken. bone

callus

calcium receptors of the parathyroid gland are located on/in _________

cell membrane

several breaks result in many small pieces between two large segments

commented fracture

the walls of the diaphysis is composed of ________ bone

compact

the disruption of blood flow to the bone results in the ____of bone cells around the fracture

death

the two ossification pathways involved in the formation of bones before birth are called __________ and ________

endochondral and intramembranous ossification

in ___________ bone develops by replacing hyaline cartilage

endochondral ossification

________________ is the connective tissue covering the inside of the bone

endosteum

the medullary cavity is lined with a delicate and incomplete membrane called the ____________ which is the location of bone stem cells

endosteum

after birth, long bones grow in length at the _______ via __________

epiphyseal plate via interstitual growth

a ___________ callus forms from the periosteum

external callus

yellow bone marrow contains ______ which may be dispersed into the bloodstream when a bone is broken

fat globules

during ________ _______ a framework is laid down that determines where bones will form

fetal development

bone that have a flattened shape ex) sternum

flat bone

a partial fracture in which only one side of the bone is broken

greenstick fracture

increases length of long bones, enhances mineralization, and improves bone density

growth hormone

clotting bloods forms a _________________

hematoma

when a bone is broken, the blood clot that initially forms around the fracture site is called a fracture ____________

hematoma

Calcitriol is _________

hypertonic

PTH Is ___________

hypertonic

Calcitonin is __________

hypotonic

a chondroblast is a __________cartilage cell

immature

one fragment is driven into the other, usually a result of compression

impacted

a __________ callus forms from the endosteum

internal callus

bones with an irregular shape ex) facial bones and vertebral bones

irregular bones

calcitriol goes with _______

kidney

your ________ is the largest sesamoid bone in the body

kneecap

_____________ is a dorsiventral curvature of the spine leading to a "hunchback" appearance

kyphosis

calcidiol goes with ________

liver

most of the bones making up the appendicular Skeleton, including the bones making the fingers and toes, are structurally classified as __________ bones

long

bones that are cylindrical in shape ex) humerus, ulna, radius, femur, tibia, fibula

long bones

clavicles are structurally classified as _________ bones and are formed by _______ ossification

long bones intramembranous

___________ is a ventral curvature of the spine leading to a "sway back" appearance

lordosis

the process of erosion of old bone along the medullary cavity and the deposition of new bone beneath the periosteum not only increase the diameter of the medullary is called __________

modeling

overall the mechanism of regulation of calcium homeostasis by calcitonin and PTH is a mechanism of ___________

negative feedback

blood vessels enter the shaft of a long bone through the _____________

nutrient foramen

occurs at an angle that is not 90 degrees

oblique fracture

at least one end of the broken bone tears through the skin

open fracture

a ___________ is an immature bone cell that creates the bony matrix. It is found in areas of bone growth, in the endosteum and periosteum.

osteoblast

the periosteal chondrocytes and _________create an external callus of hyaline cartilage and bone

osteoblasts

_________reobsorb dead bone

osteoclasts

a __________ is a large multi-nucleated cell related to macrophages and resorbs bone tissue

osteoclasts

the microscopic structural unit of bone is the __________

osteon

the structural and functional unit of the compact bone tissue is the ______

osteon

_____________ is a disease characterized by a decrease in bone mass that occurs when the rate of bone resorption exceeds the rate of bone formation, a common occurrence as the body ages.

osteoporosis

a bone disease due to loss bone mass

osteoporosis

in ____________ a new bone is formed in an attempt to keep up with the resorption by the overactive osteoclasts, but that new bone is produced haphazardly

paget's disease

the ___________ hormone inhibits osteoblasts and activates osteoclasts in calcium homeostasis

parathyroid

____________ stimulates the release of calcium from bone tissue

parathyroid hormone

stimulates osteoclast proliferation and resorption of bone by osteoclasts; promotes reabsorption of calcium by kidney tubules; indirectly increases calcium absorption. by small intestine

parathyroid hormone

excess ___________ hormone will result in increased bone loss and an increase in serum calcium levels

parathyroid hormone (hyperparathyroidism)

______________ is a membrane that covers the cartilage

perichondrium

the ___________ is the connective tissue covering the outside of the bone

periosteum

what is bone remodeling?

process in which reabsorption of old or damaged bone takes place on the same surface where osteoblasts lay new bone to replace that which is resorbed

which zone of growth is where mitosis occurs

proliferative zone

____________ is a lifelong process in which bones is resorbed and replaced in response to stress

remodeling

process in which resorption of old or damaged bone takes place on the same surface where osteoblasts lay new bone to replace that which is resorbed

remodeling

which zone of growth is where matrix production takes place

reserve zone

calcium goes with _________

salmon

____________ is the lateral curvature of the spine, thoracic or lumbar

scoliosis

a bone that is formed inside tendons to make a joint function is known as a _________ bone

sesamoid

promote osteoblastic activity and production of bone matrix; responsible for adolescent growth spurt; promote conversion of epiphyseal plate to epiphyseal line

sex hormones

bones are structurally classified in five groups according to their _________

shape

what does calcitriol target?

skin, liver, and kidneys

____________ is a birth defect in which the neural canal does not completely fuse, leaving a cleft in at least one vertebra

spina bifida

bone segments are pulled apart as a result of a twisting motion

spiral fracture

the dipole refers to the _______ specifically found In ________ bones

spongy bone tissue found in flat bones

Vitamin goes with ________

sunlight

what determines the flexibility of the bones?

the level of collagen fibers present in bone tissue

what endocrine secretes PTH?

the parathyroid hormone

the periosteum is covering all of the bones except _________________

the parts of the bones involved in moveable joints

what is the role of the skin in calcium homeostasis?

the skin houses keratinocytes -the cells that use UV sun rays to convert cholesterol into vitamin D

what endocrine gland secretes calcitonin?

the thyroid gland

what allows the bones to resist compressional forces?

their degree of mineralization

when blood levels of calcium get too high, the _____________is stimulated to release ____________

thyroid calcitonin

stimulates bone growth and promotes synthesis of bone matrix

thyroxine

the body deposits calcium in the bones when blood levels get __________ and it releases calcium when blood levels drop ________

too high too low

occurs straight across the long axis of the bone

transverse

vitamin ________ is necessary for healthy bone, and may be obtained from leafy green vegetables

vitamin k

what is bone homeostasis?

when bones grow, remodeling causes bone tissue to be restricted to maintain the shape and structure of the bone

Could calcium concentration in the blood be maintained in a steady range in absence of calcitonin?

yes. the process needs mainly needs calcitriol and PTH to maintain a steady range but doesn't necessarily need calcitonin.

the zone of bone growth that contains the primary sponglosa and the secondary songlosa

zone of ossification