Lecture 13- Muscle Tissue

Question 1

What is Myalgia?

Answer 1

Muscle pain

Question 2

What is Myasthenia?

Answer 2

Muscle weakness

Question 3

What is Myocardium?

Answer 3

Muscle component in the heart

Question 4

What is Myopathy?

Answer 4

Any disease of the muscle

Question 5

What is myoclonos?

Answer 5

Muscle spasm

Question 6

Difference between Skeletal muscle and cardiac muscle

Answer 6

Skeletal- Direct nerve communication, multinucleated

Cardiac- Indirect nerve communication , 1 or 2 nuclei

Question 7

Myogoblin?

Answer 7

Myoglobin has a higher affinity than haemogoblin and is a n oxygen storage molecule.

Question 8

What is the sarcoplasm?

Answer 8

The cytoplasm of a muscle cell

Question 9

Sarcosome?

Answer 9

The mitochondrian

Question 10

What is a sarcomere?

Answer 10

Contraction unit in striated muscle

Question 11

What is the sarcoplasmic reticulum?

Answer 11

The smooth endoplasmic reticulum of a muscle cell

Question 12

What is the skeletal muscle structure?

Answer 12

Epimysium- surrounds multiple fasicles 
Perimysium- surrounds a singular fascicles 
Endomysium- wraps around muscle fibre
Point of origin- tension created
Point of insertion- movement

Question 13

What are the muscle speeds?

Answer 13

Slow twitch- Rich in myogoblin, aerobic, rich capillary supply, fatty acid stores. Endurance activities. Lots of mitochondria, lots of cytochromes
Intermediate Twitch- Rich blood supply, aerobic, lots of myogoblin, many mitochondria, lots of cytochromes, fatty acids and glycogen Moderate activities- walking, standing
Fast twitch- Fewer myogoblin, anaerobic, poor capillary supply, glycogen storage , Few mitochondria, few cytochromes. For sprinting

Question 14

Skeletal muscle Histology in Transverse and longitudinal

Answer 14

TS- Peripheral nucleus

LS- Nuclei in rows

Question 15

What is cell hypertrophy?

Answer 15

Enlargement of their individual cells

Question 16

What is cell hyperplasia?

Answer 16

Multiplication of their cells

Question 17

What is the structure of smooth muscle cells?

Answer 17

No striations, spindle-shaped, single central nucleus.
Slower contraction, less ATP required.
Responds top stimuli: nerve signals, hormones

Question 18

Ultra structure of smooth muscle cells?

Answer 18

Gap junctions connect adjacent smooth muscle cells.

Question 19

How are smooth muscle cells innervated?

Answer 19

Innervated by the ANS fibres that release their neurotransmitters from varicosities into a wide synaptic cleft.

Question 20

Conducting system of the heart

Answer 20

1) SA NODE receives STIMULUS and causes contraction of atrium
2) Pulse travels down the AV NODE AND stimulus goes to the bundle of Hiss
3) Goes down the PURKINJEE fibres and causes contraction of the bottom part upwards
4) Delay of signalling between nodes to allow fully pump the contraction in the cardiac muscle.