Muscle and Vessel VHA

Question 1

what is the only voluntary muscle?

Answer 1

skeletal muscle

Question 2

what are 2 defining features of skeletal muscle?

Answer 2

striated

peripheral nuclei

Question 3

Zoom in on a muscle cell fibers

Answer 3

muscle cell -> fascicles -> myofibrils -> myofilaments (actin and myosin)

Question 4

what do T-tubules allow for?

Answer 4

simultaneous contraction

Question 5

What connects to the Z-disc?

Answer 5

actin filaments

Question 6

What region does not change during contraction? What does this region contain?

Answer 6

A-band

A-band contains both thin (actin) and thick (myosin) filaments

A-band is innermost region of sarcomere

Question 7

I band

Answer 7

space between the A-band and Z-disc that contains mostly actin

Question 8

Sarcomere

Answer 8

spans from Z-disc to Z-disc

contracts

Question 9

Which band causes striations on H+E stain?

Answer 9

A-band

Question 10

What are the dots on low power electron micrograph of muscle?

Answer 10

mitochondria

Question 11

4 key features of cardiac muscle

Answer 11

branching fibers

striated

centrally located nuclei

intercalated discs

Question 12

intercalated discs

Answer 12

connect cardiomyocytes

Question 13

Lf pigment

Answer 13

yellow dots in cardiac muscle

sign of aging

Question 14

What are intercalated discs composed of?

Answer 14

adherens junction, desmosomes and gap junctions

intercalated discs are intercellular junctions that link cells

Question 15

Signs of MI in cardiomyocytes

Answer 15

eosinophilic

lympocytes and macrophages

pyknotic nuclei

Question 16

pyknotic nuclei

Answer 16

irreversible condensation of chromatin seen in necrosis / apoptosis

Question 17

2 defining features of smooth muscle

Answer 17

centrally located nuclei

non-striated

Question 18

what is the shortest muscle type?

Answer 18

smooth muscle

Question 19

does smooth muscle have sarcomeres / striations?

Answer 19

no!

Question 20

what does contraction look like in smooth muscle?

Answer 20

twisting and contortion of cell + nuclei

Question 21

Which cell type is collagen normally present with? How do we stain it?

Answer 21

smooth muscle

collagen stains blue with trichome

Question 22

3 blood vessel tunics

Answer 22

tunica intima (up against blood, intermost)

tunica media

tunica adventitia

Question 23

tunica intima is comprised of …

Answer 23

endothelial tissue and sub-endothelial connective tissue

Question 24

tunica media is comprised of …

Answer 24

mostly smooth muscle

Question 25

In which vessel is the tunica media thicker?

Answer 25

arteries

Question 26

tunica adventitia is comprised of …

Answer 26

connective tissue layer

Question 27

Elastic lamina

Answer 27

allow recoil of blood vessel

there is an internal and external elastic lamina

Question 28

Why do arteries have thicker walls?

Answer 28

they are under higher pressure

Question 29

What type of vessels have valves?

Answer 29

veins have valves to prevent the reverse flow of blood

Question 30

What stains elastic fibers?

Answer 30

Verhoff stain

Question 31

How can you easily determine veins?

Answer 31

irregular shape

Question 32

what does an atherosclerotic plaque look like?

Answer 32

a mix of cells

Question 33

what layer thickens in atherosclerosis?

Answer 33

tunica intima