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Flashcards in Structure Deck (28)
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1

What are the skeletal functions? (7)

Support framework, forms boundaries, attach tendons and muscles, for movement, haemopoiesis ( making blood cell), mineral homeostasis and triglyceride storage ( yellow bone marrow)

2

What is an oestogenic cell?

Unspecialised stem cells and only bone cell to divide

3

What is an osteoblasts?

Bone building cells by secreting collagen, initiating calcification. They surround themselves with extracellular matrix, become trapped in their secretions and become osteocytes.

4

What is an osteocyte?

Mature bone cells

5

What is an osteoclasts?

Breaks bone down, it's has a ruffled border which releases lysosomal enzymes and acids to digest bone. They are huge cells formed from many monocytes.

6

What is reabsorption?

Break down of bone extracellular matrix.

7

What is an osteon?

The structural unit of compact bone.

8

Describe the four parts of the osteon and what they do.

Central canal provides blood supple via nerves and vessels.
Lamellae is the concentric rings of calcified extracellular matrix with minerals and collagen.
Lacunae are small spaces between lamellae which hold osteocytes.
Canaliculi is a system of interconnect canal which supply nutrients and remove waste.

9

What is spongy bone?

It is an irregular lattice of thin columns call trabeculae. They contain lamellae, lacunae and canaliculi.

10

What is the extracellular matrix of bone?

Surround separates cells and made mostly of calcium phosphate. They minerals are deposited and crystallised (harden) in a framework formed by collagen fibres.

11

What is a long bone?

The length is longer than width. A shaft called diaphysis and 2 heads called epiphyses.

12

What is an epiphyseal plate?

Separate diaphysis and epiphysis, it is a layer of hyaline cartilage and allows the bone to grow.

13

What is the structure of epiphysis?

Thin outer compact bone covered by hyaline cartilage and inner spongy bone with red marrow.

14

What is the structure of diaphysis?

Outer compact bone covered by periosteum and a central medullary canal with red and yellow bone marrow.

15

What is the periosteum?

Cover compact bone unless it is covered by hyaline cartilage.

16

What is the function of periosteum?

Protect bone, vascular membrane ( provides blood) and attaches ligaments and tendons

17

What are the two layers of the periosteum?

Outer fibrous layer- tough and protects the bone.
Inner osteogenic layer - osteoblasts and osteoclasts for growth and repair.

18

What is the endosteum?

The layer under compact bone and separates spongy with compact bone.

19

What are short bones?

Carpels and tarsals

20

What are irregular bones?

Vertebrae

21

What are flat bones?

Scapula and skull

22

What are sesamoid bones?

Patella

23

What are the two types of bone marrow?

Red bone marrow - red blood cells, platelets, white blood cells created
Yellow bone marrow - creates fat cells, and some WBC

24

What is hypercalcaemia?

High blood calcium, increase osteoblasts activity

25

What is hypocalcaemia?

Low blood calcium and osteoclasts activity breaks down bone and release Ca into the blood.

26

What is the parathyroid hormone?

Increases blood calcium by increasing osteoclasts activity, kidneys to reabsorption and retaining Ca in the blood and stimulate calcitriol ( promotes Ca uptake from food)

27

What is calcitonin?

Secreted by thyroid gland. Decrease blood calcium by inhibiting osteoclast and promoting osteoblasts depositing calcium in the bone.

28

What are the 5 axial parts?

Skull, chest, hyroid throat bone, ossicles and vertebral column.