017 CAL: skeletal muscle histology

Question 1

what is this an image of?

Answer 1

• skeletal muscle in iron haematoxylin stain, longitudinal section

Question 2

what type of muscle is this and how do you know?

Answer 2

• skeletal
• striations
• nuclei on periphery

Question 3

what type of muscle is this and what is I, H, A?

Answer 3

• skeletal
• I = light I band (actin)
• H = H zone = myosin only
• A = dark A band (myosin and actin overlap)

Question 4

what is this an image of?

Answer 4

• skeletal muscle in transverse
• silver stain
• can see reticular fibres

Question 5

what is A?

Answer 5

adipose tissue

Question 6

what is B?

Answer 6

blood vessels

Question 7

what are the red arrows pointing to?

Answer 7

• endomysium
• connective tissue around each individual muscle fibre

Question 8

what is stained black in this image?

Answer 8

• reticular fibres
• in the endomysium, perimysium, epimysium, around blood vessels, around adipose tissue

Question 9

what is this an image of?

Answer 9

• skeletal muscle H and E
• transverse and longitudinal section
• transverse = blobs
• longitudinal = long fibres

Question 10

what is this an image of?

Answer 10

• skeletal muscle inserting into a tendon (at bottom in orange)

Question 11

why are there so many nuclei between the junction of the muscle and tendon?

Answer 11

• fibroblast nuclei

Question 12

what is this an image of?

Answer 12

• skeletal muscles and its motor end plates / neuromuscular junctions
• iron haematoxylin stain

Question 13

what is NT?

Answer 13

nerve trunk

Question 14

what is MEP?

Answer 14

motor end plate

Question 15

what is B?

Answer 15

branch of axons

Question 16

what is BV?

Answer 16

blood vessel

Question 17

what is TE?

Answer 17

trailing end = thin end of axon = probably a muscle spindle

Question 18

what is MS?

Answer 18

muscle spindle

Question 19

what is MS?

Answer 19

muscle spindle

Question 20

what is skM

Answer 20

skeletal muscle fibre

Question 21

what is this an image of?

Answer 21

• skeletal and smooth muscle and fibrous connective tissue ( F = fibroblasts)
• in oesophagus
• H and E stain

Question 22

describe the differences between Sk and Sm

Answer 22

-Sk = round oval nuclei at periphery of cell, very long cells, striated, some cells have multiple nuclei, some have none
- Sm = elongated nuclei, spindle shape, in centre of cell, each cell has 1 nucleus

Question 23

how do you histologically differentiate between fibroblasts and smooth muscle nuclei?

Answer 23

• fibroblast nuclei are pointy and curved
• smooth muscle are more cigar-shaped in spindle shape cells

Question 24

what type of muscle is this?

Answer 24

• smooth muscle in transverse

Question 25

describe what is between the smooth muscle fibres/cells in this image

Answer 25

- septae of connective tissue (mostly type 1 collagen and fibroblasts) - no equivalent endomysium = smooth muscle cells are in direct contact with each other via gap junctions

Question 26

what is this an image of?

Answer 26

- skeletal and smooth muscle in transverse of the oesophagus CP = capillary

Question 27

what is this an image of?

Answer 27

- smooth muscle and myenteric ganglion of stomach

Question 28

what is LM and CM?

Answer 28

- longitudinal muscle and circular muscle of the muscularis externa

Question 29

what is MP?

Answer 29

myenteric plecus

Question 30

what is GC?

Answer 30

glial cells in the ganglia of the myenteric plexus

Question 31

what is N?

Answer 31

Nerve cells

Question 32

what is Ct?

Answer 32

- connective tissue outlining the ganglion

Question 33

what is the histological difference between nerve cells and glial cells?

Answer 33

- glial cells = smaller denser nuclei - nerve cell bodies = large clear, a circular nucleus with a prominent nucleolus and lots of cytoplasms

Question 34

what is this an image of?

Answer 34

- smooth muscle of the urinary bladder

Question 35

what is the epithelium type in this image?

Answer 35

- transitional epithelium = urinary