Brainscape's Knowledge GenomeTM

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


See full index

Anatomy and Physiology > Bone Tissue Lecture 2 > Flashcards

Bone Tissue Lecture 2 Flashcards

1
Q

Bone Blood Supply Overview

A
  • Rich in blood supply due to high metabolic activity and constant remodeling.
  • Blood supply is crucial for maintaining structural integrity and providing nutrients.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
1
Q

Arteries and Veins

Four major arteries and veins supply bone tissue:

A
  • Periosteal arteries/veins
  • Nutrient artery/vein
  • Metaphyseal arteries/veins
  • Epiphyseal artery/vein
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Periosteal Arteries/Veins

A
  • Enter through Volkmann’s canals.
  • Supply blood to and from the outer portion of compact bone and periosteum.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Nutrient Artery/Vein

A
  • Enter through the nutrient foramen in the diaphysis.
  • Supply blood to the inner portion of compact bone and proximal spongy bone.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Metaphyseal Arteries/Veins

A
  • Enter at the metaphysis portion.
  • Supply blood to the metaphysis and red bone marrow.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Epiphyseal Artery/Vein

A
  • Enter at the epiphysis portion.
  • Supply blood to the epiphysis and red bone marrow.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Bone Remodeling

Process

A
  • Lifelong process
  • Mature bone tissue is replaced by new bone tissue.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Bone Remodeling

Purpose

A
  • Maintains structural integrity
  • Strengthens high-stress areas
  • Controls reshaping after injuries
  • Repairs micro-damage
  • Maintains blood calcium homeostasis.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Bone Remodeling

Bone Resorption

A
  • Osteoclasts break down bone matrix.
  • Removes collagen and minerals, releasing calcium into the blood.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Bone Remodeling

Bone Deposition

A
  • Osteoblasts create new bone ECM.
  • Lay down osteoid, the organic bone component.
  • Deposit minerals, mainly calcium, from the blood.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Bone Remodeling

Simultaneous Processes

A
  • Resorption and deposition work together.
  • Respond to stress on the bone.
  • Wolff’s Law: bone is added where needed and removed where not.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Factors Affecting Bone Growth

Minerals

A

Calcium, phosphorus, fluoride, magnesium, manganese.

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

Factors Affecting Bone Growth

Vitamins

A
  • Vitamin A promotes osteoblasts.
  • Vitamin C for collagen.
  • Vitamin D aids calcium absorption.
  • Vitamin K & B12 for bone proteins.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Factors Affecting Bone Growth

Hormones

A
  • Thyroid hormones (T3 & T4) promote bone growth.
  • GH stimulates IGFs for growth.
  • Sex hormones affect bone growth/remodeling.
  • Hormones in calcium homeostasis (calcitonin, PTH).
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Calcium Functions

A
  • Essential for nerve and muscle functioning.
  • Key in blood clotting.
  • Important for various body chemical reactions.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Calcium Regulation

A
  • Calcium levels must be tightly controlled (8.5 - 10.5 mg/dL).
    Deviations can be fatal:
  • Hypercalcemia (>10.5 mg/dL) ➡️ Cardiac arrest.
  • Hypocalcemia (<8.5 mg/dL) ➡️ Respiratory arrest.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Calcium Regulation Locations

A

Bone:
Resorption increases blood Ca2+.
Deposition decreases blood Ca2+.
Kidney:
Reabsorption increases blood Ca2+.
Decreased reabsorption decreases blood Ca2+.
Gastrointestinal Tract:
Absorption increases blood Ca2+.
Decreased absorption decreases blood Ca2+.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Calcium Regulating Hormones

A
  • Calcitonin: Decreases blood Ca2+.
  • Parathyroid Hormone (PTH): Increases blood Ca2+.
  • Calcitriol (Vitamin D): Increases blood Ca2+.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Calcitonin

A
  • Produced by thyroid gland’s parafollicular cells.
  • Decreases blood Ca2+.
  • Antagonistic to PTH and calcitriol.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Calcitonin Mechanism

A
  • Decreases bone resorption.
  • Inhibits osteoclasts, favoring osteoblasts.
  • Decreases kidney Ca2+ reabsorption.
  • More Ca2+ excreted, lowering blood Ca2+.
20
Q

Parathyroid Hormone (PTH)

A
  • Produced by parathyroid glands.
  • Increases blood Ca2+.
  • Antagonistic to calcitonin, synergistic to calcitriol.
21
Q

PTH Mechanism

A
  • Increases bone resorption.
  • Activates osteoclasts, favoring bone breakdown.

Kidney actions:
* Increases Ca2+ reabsorption.
* Activates calcitriol.

22
Q

PTH Regulation

A

Controlled by negative feedback.

23
Q

Calcitriol

A
  • Produced in skin from UV-activated cholesterol.
  • Increases blood Ca2+.
  • Antagonistic to calcitonin, synergistic to PTH.
24
Q

Calcitriol Mechanism

A
  • Increases intestinal Ca2+ absorption.
  • Boosts blood Ca2+ levels.
25
Q

Fractures

A
  • Any break in the bone.
  • Types vary by severity, location, and cause.
26
Q

Open Fractures (Compound)

A
  • Definition: bone ends protrude through the skin.
  • Complications: infection, non-union.
  • Treatment: surgery, antibiotics.
27
Q

Closed Fractures (Simple)

A
  • Definition: bone ends don’t pierce the skin.
  • May not need surgery depending on displacement.
28
Q

Comminuted Fractures

A
  • Bone broken in multiple places forming fragments.
  • Requires surgery with internal/external fixation.
29
Q

Greenstick Fractures

A
  • Incomplete, one side broken, other bent.
  • Common in children due to more organic material.
30
Q

Impacted Fractures

A
  • One bone end driven into the other.
  • Common in car accidents.
31
Q

Transverse & Oblique Fractures

A
  • Transverse: perpendicular to bone length.
  • Oblique: broken on an angle.
32
Q

Spiral Fractures

A
  • Looks like a corkscrew around the bone.
  • Occurs due to a twisting motion.
33
Q

Pott’s Fractures

A
  • In distal fibula with ankle sprain.
  • Serious injury to distal tibial articulation.
34
Q

Colles’ Fractures

A

Distal radius fracture, distal part displaced upwards.

35
Q

Avulsion Fractures

A
  • Small piece of bone attached to tendon or ligament pulled away.
  • Common in young athletes.
36
Q

Stress Fractures

A
  • Microscopic fissures due to repetitive strenuous activities.
  • Commonly missed by x-rays.
37
Q

Growth Plate Fractures

A

Break in child/teen growth plate can result in limb deformities.

38
Q

Vertebral Compression Fractures (VCF)

A
  • Vertebrae fracture, compressed into wedge shape.
  • Often in osteoporosis or trauma.
39
Q

Osteoporosis

A
  • “Porous bone.”
  • Loss of bone mass with deteriorating bone microarchitecture.
  • Bone resorption > bone deposition.
  • Caused by: hormones, diet, exercise, drugs, genetics.
  • More common in elderly and women.
40
Q

Osteomalacia & Rickets

A
  • Failure of bones to calcify.
  • In children, Rickets; in adults, Osteomalacia.
  • “Soft bones” due to calcium deficiency.
  • Vitamin D, sunlight, diet deficiency.
  • Rickets causes bowing, fractures; osteomalacia affects bone mineral ratio.
  • Both caused by vitamin D deficiency.
41
Q

Formation of Fracture Hematoma (Reactive Phase)

Fracture repair step 1

A
  • Exposed blood vessels clot at fracture.
  • Circulation stops, nearby bone cells die.
  • Inflammation from dead cells.
  • Phagocytes and osteoclasts remove debris.
42
Q

Fibrocartilaginous Callus Formation

Fracture repair step 2

A
  • Fibroblasts lay down collagen fibers.
  • Chondrocytes produce fibrocartilage.
  • Callus formation.
  • Lasts about 3 weeks.
43
Q

Bony Callus Formation

Fracture repair step 3

A
  • Osteogenic cells become osteoblasts.
  • Convert fibrocartilage into spongy bone trabeculae.
  • Joins living and dead portions of bone fragments.
  • Lasts around 3-4 months.
44
Q

Bone Remodeling

fracture repair step 4

A
  • Osteoclasts resorb remaining dead bone fragments.
  • Compact bone replaces spongy bone.
  • Occurs around the periphery.
45
Q

X-Ray or Radiography

A
  • Electron beams pass through objects.
  • Soft tissue and air are translucent or black.
  • Dense objects like bone, metals appear grey or white.
    Radiolucent: Less dense, lets x-rays through.
    Radiopaque: Dense, resists x-rays.
46
Q

DEXA Scan (Dual X-Ray Absorptiometry)

A
  • Measures bone density.
  • Tracks bone loss and diagnoses osteoporosis.
47
Q

Bone Scan

A
  • Radioactive tracer taken up by living bone tissue.
  • Scanning device detects high or low activity.
  • Hot Spots: Indicate higher metabolism (e.g., cancer).
  • Cold Spots: Indicate healed fractures, arthritis.
  • Most useful bone imaging method due to efficiency, accuracy, and reduced radiation.

Anatomy and Physiology (21 decks)

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