Histology

Question 1

Where are the multiple nuclei located in skeletal muscle fibres?

Answer 1

Periphery, just under the cell membrane (sarcolemma)

Question 2

What are muscle fibres called when they are grouped into bundles?

Answer 2

Fascicles

Question 3

**The connective tissue that surrounds the whole muscle?

Answer 3

Epimysium

Question 4

**The connective tissue that surrounds a single fascile?

Answer 4

Perimysium

Question 5

**The connective tissue that surrounds a single muscle fibre?

Answer 5

Endomysium

Question 6

What is the term for the space in the ECM which chondrocytes live within?

Answer 6

Lacuna

Question 7

What makes up the ECM in hyaline cartilage?

Answer 7

Water (75%), Type II colagen, proteoglycan aggregates made up of GAGs

Question 8

What are the 3 main types of cartilage?

Answer 8

Hyaline, elastic (eg. pinna) and fibrocartilage

Question 9

True or false: both cortical and cancellous (trabecular) bone are lamellar (made up of layers)

Answer 9

True

Question 10

What is the name of the canals that lie in the longitudinal plane of bone and supplies vasculature to the bone?

Answer 10

Haversian canals

Question 11

Cement lines

Answer 11

The lines often visible surround the osteon

Question 12

Osteoprogenitor cells

Answer 12

located on bone surfaces, for example under the periosteum, these cells serve as a pool of reserve osteoblasts

Question 13

Osteoblasts

Answer 13

Bone forming cells found on the surface of developing bone.

Question 14

Osteoclasts

Answer 14

They are found on the surface of bone and are responsible for bone resorption.

Question 15

Osteocytes

Answer 15

A bone cell trapped within the bone matrix.

Question 16

Osteon

Answer 16

Functional unit of cortical bone - consists of concentric lamellae of compact bone tissue that surround a central canal, the haversian canal

Question 17

How is bone remodelled?

Answer 17

A number of osteoclasts will congregate and begin to ‘drill’ into the bone, forming a tunnel. A blood vessel will grow into the tunnel bringing with it osteoblasts which line the tunnel and begin laying down new lamellar bone. This process continues until only the space of a Haversian canal remains.
The osteoblasts secrete collagen, glycosaminoglycans (GAGs), proteoglycans and other organic components of the matrix which is collectively termed osteoid. This then becomes mineralized over time in the extracellular space.

Question 18

Woven bone

Answer 18

Bone placed down during healing, which has the collagen fibres laid down in a haphazard fashion rather than all in one plane. It is not as strong so is eventually remodelled into lamellar bone.