Chapter 6 Quiz Questions Flashcards
(27 cards)
What critical functions for the body does the skeletal system perform? (5)
- Supports the body
- Facilitates movement
- Protects internal organs
- Produces blood cells
- Stores and releases minerals and fat
What is the function of the bone matrix?
Reservoir for Ca2+ and Phosphorus.
Where are the 4 locations a long bone is found in the body?
HUR + FTF + MP + MP
- Arms –> Humerus + Ulna + Radius
- Legs –>Femur + Tibia + Fibula
- Fingers –> Metacarpals + Phalanges
- Toes –> Metatarsals + Phalanges
What substances make up the intercellular materials of bone?
mineral salts (calcium phosphate and calcium carbonate), mainly collagen fibres, and water.
What are the 5 types of bones?
- Long bone
- Short Bone
- Flat bone
- Irregular bone
- Sesamoid bone
What is a Haversian Canal?
A small channel running through the compact bone that carries small blood vessels and nerves.
Also known as a central canal.
What are canaliculi?
lacunae + jelly
Minute channels radiating out of the lacunae that contain cytoplasmic projections from the osteocytes.
- Connect osteocytes in the lacunae with each other, and with central canals.
What are the three general classes of bone markings?
- Articulations - (2 bone surfaces come together)
- Projections - (An area of a bone that projects above the surface of the bone)
- Holes - (opening or groove in the bone that allows blood vessels and nerves to enter the bone)
What are the 4 types of bone cells are found within bone tissue?
1: Osteoblasts
2: Osteocytes
3: Osteogenic Cells
4: Osteoclasts
Osteoblasts
The bone cell responsible for forming new bone.
-Found within growing bone portions.
- Do not divide.
- Synthesize and secrete the collagen matrix and calcium salts.
Osteocytes
Think of matrix being all around us
The primary cell of mature bone and the most common type of bone cell.
-They maintain the mineral concentration of the matrix via secretion of enzymes.
Osteogenic Cells
-Only bone cell that divides.
- Have high mitotic activity
- Differentiate and develop into osteoblasts.
Osteoclasts
- The cell responsible for bone resorption, or breakdown.
- Continuously breaking down old bone, while osteoblasts form new bones.
Name 2 types of ossification, and give an ex in which each process occurs.
- Intramembranous ossification (Mandible and flat skull bones)
- Endochondral Ossification ( Tibia, base of skull, and most bones of body)
What are secondary ossification centres?
Places that develop in the epiphyses and lay down spongy bone, infiltrated by blood vessels.
What is the name of the structure primarily involved in the increase in the length of long bones?
The Epiphyseal Plate (line)
What is bone remodelling?
The constant replacement of old bone with new bone.
List the factors required for bone remodelling. (6)
- Calcium
- Phosphorous
- Magnesium
- Vitamins (A, C, D, B12)
- Growth hormones
- Sex hormones
Which two hormones regulate Calcium homeostasis?
- Parathyroid Hormone (PTH)
- Calcitonin
What are 4 functions of the skeleton?
- Acts as Ca2+ storage area.
- Transmits forces to do work.
- Acts as support for body soft tissue.
- Acts as protection for internal organs.
These cells are unspecialized and derived from mesenchyme, which develop into osteoblasts.
a. Osteoclasts
b. Osteocytes
c. Osteomedullary
d. Osteoprogenitor
d) Osteporogenitor
Rings composed of hard, calcified matrix surrounding the Haversian canals are known as:
a. Canaliculi
b. Lacunae
c. Concentric lamellae
d. Trabeculae
e. Volkmann’s canals
c) Concentric Lamellae
When an osteoblast becomes isolated in a lacuna, it is transformed into a(n):
a. Macrophage
b. Osteocyte
c. Osteoclast
d. Fibroblast
e. Osteal fibre
b) Osteocyte
What structure allows the diaphysis of the bone to increase in length until early childhood, and to shape the articular surfaces?
Epiphyseal Plate
