A&P CH6: The Skeletal System (lecture)

What general effects do the hormones P T H, calcitriol, and calcitonin have on blood calcium levels?

PTH and calcitriol increase blood calcium levels, calcitonin decrease blood calcium levels in bodily fluids

How would a bone's strength be affected if the ratio of collagen to calcium increased?

the more calcium, the more strength

Why would you expect the arm bones of a weight-lifter to be thicker and heavier than those of a jogger?

the more stressed the bone is, the more thicker and stronger

A child who enters puberty several years later than the average age is generally taller than average as an adult. Why?

the more time gives the bone time to grow before puberty, where bone growth accelerates, and after puberty it stops.

A sample of a long bone shows concentric layers surrounding a central canal. Is it from the shaft or the end of the bone?

where ever there is compact bone

Why is osteoporosis more common in older women than in older men?

women stop producing estrogen while men keep producing androgen

During intramembranous ossification, which type of tissue is replaced by bone?

embryonic or fetal connective tissue

How could x-rays of the femur be used to determine if a person had reached full height?

if the x-rays show the epiphyseal line, the former location of epiphyseal cartilage

Why are pregnant women given calcium supplements and encouraged to drink milk even though their skeletons are fully formed?

it is absorbed in the bloodstream during prenatal development

Describe bone remodeling.

it recycles and renews organic and mineral components of bone matrix

If the activity of osteoclasts exceeds that of osteoblasts in a bone, how will the mass of the bone be affected?

it would decrease since there are more cells being absorbed than built

identify the four general shapes of bones

long, short, irregular, and flat

Which of the following matches the cell with its function?

osteoblasts: ossification

Mature bone cells are known as __________, bone-building cells are called ___________, and ____________ are bone-resorbing cells.

osteocytes , osteoblasts, osteoclasts

Narrow sheets of calcified matrix are referred to as

Lamellae

Which of the following accounts for almost two-thirds of the mass of bone tissue?

Calcium phosphate

What is the difference between a closed fracture and an open fracture?

Closed fracture is completely internal and only can be seen with an x-ray. An open fracture projects through the skin and is more susceptible to bacteria and infection.

What is the main difference between spongy bone and compact bone?

Compact bones contain osteons; spongy bones contain trabeculae.

Which of the following occurs in intramembranous ossification?

Fibrous connective tissue is converted to bone tissue, which first resembles spongy bone

A round opening through the bone that acts as a passageway for blood vessels or nerves referred to as a __________.

Foramen

Define osteopenia

bones become thinner and weaker because osteoblasts activity slows and osteoclasts activity remains the same

Name the 5 primary functions of the skeletal system

support, leverage, protection, blood cell production, and storage of minerals and lipids