Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Skeletal Physiology: Bone Health > Lecture 1 > Flashcards

Lecture 1 Flashcards

1
Q

What is Bone made up of

A

Type 1 Collagen

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is Bone filled with

A

Hydroxyapatite

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Calcium management

A

Skeleton acts as a reservoir for Ca

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Types of hormones which offer skeletal management

A

Sex Steroid, thyroxine, corticosteroids and insulin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

4 cell types relevant to bone formation and metabolism

A

Osteoblasts, Osteoclasts, Osteocytes, Osteoprogenitor

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Osteoblasts position

A

Bone Surface

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Osteoblasts Feature

A

Responsible for laying down bone

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Osteoclasts Position

A

Bone surface but low numbers

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Osteoclasts Features

A

Move across bone surface reabsorbing bone, multinucleated and contain many mitochondria

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Osteocytes Position

A

Cannot divide, most abundant cell in bone, networked by canaliculi

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Osteocytes Features

A

Cannot divide, most abundant cell in bone. Networked by canaliculi

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Three Hormones that play vital roles

A

Calcitrol, Parathyroid Hormone, Calcitonin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Calcitrol

A

Active form of Vitamin D

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Role of Calcitrol

A

Increases blood Ca2+

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

How does Calcitriol increase Ca2+

A

Increase calcium and phosphate absorption from Intestines
Increasing calcium resorption from bone via indirect osteoclast and direct osteoblast stimulation, decreasing urinary excretion of calcium, by increasing calcium reabsorption by kidneys.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

How does calcitriol act

A

Bids to nuclear receptor protein on target tissue and regulate gene expression

17
Q

Parathyroid Hormone role

A

Increase calcium resorption from bone via indirect osteoclast stimulation
Decreasing urinary excretion of calcium, by increasing calcium resorption by kidneys
Increasing urinary excretion of inorganic phosphate, by decreasing Pi reabsorption by kidneys
Stimulating calcitriol production in the kidneys

18
Q

Role of Calcitonin

A

Decreases blood Ca2+

19
Q

How does Calcitonin decrease Ca2+

A

Inhibiting calcium resorption from bone via direct osteoblast stimulation
Increasing urinary excretion of calcium and inorganic phosphate by decreasing resorption by kidneys.

20
Q

Bone Mineral Density

A

g bone mineral per cm^2

21
Q

Peak Bone Mass

A

The amount of bony tissue present at the end of the skeletal maturation

22
Q

Lower BMD=

A

Greater chance/ severity of fracture

23
Q

Bone Density decreases Over time

A

Oestrogen inhibits bone resorption by reducing osteoblast numbers and activity. A lack if oestrogen allows osteoclast to be more active allowing bone resorption to occur.

24
Q

Osteoporosis

A

BMD lies 2.5 standard deviations or more below the average value for young healthy person (T- score)

25
Q

Osteopenia

A

T- Score between -1 to -2.5

26
Q

Typical stress points

A

Spine, Hip and wrist

27
Q

Why are women more at risk

A 
Menopausal effect (Oestrogen)
Affected by previous pregnancies
Women tend to live longer
28
Q

Osteomalacia

A

softening of the bones, typically through a deficiency of vitamin D or calcium.

29
Q

Mothers at risk due to

A
  • Low Ca intake
  • Low sun exposure
  • Long periods of lactation
30
Q

Role of Vitamin D3

A

Bone growth, Cells of the immune system, pancreas, skin

31
Q

Causes in VD deficiency

A

Poor diet, inability to absorb/ metabolise vitamin D3, low sunlight exposure

32
Q

Vitamin D3 Formation

A
  1. Sunlight (UV), shining on the skin
  2. Inactive form of VD travels to the liver and then the kidneys in a 2 step activation pathway.
  3. Active VD can then enter cells and stimulate receptor protein to bind to DNA in the nucleus, acting as a regulator for hundreds of genes.
33
Q

How is VD3 deficiency a risk factor

A

Risk factor for osteoporosis and osteomalacia

34
Q

Why is sufficient Calcium vital for achieving a high peak bone mass

A

Peak total body BMD and BMC is attained by the age of 22 yrs and 26 yrs
During adolescence around 50 % of peak bone mass is laid down

Skeletal Physiology: Bone Health (2 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions