Muscle Flashcards
Why are skeletal muscle striated
The myofibrillar are in register
What shape are skeletal muscles in cross-section
Polygonal
What is skeletal muscle cell membrane known as
Sarcolemma
Where are nuclei are present in skeletal muscle cells
Towards the edge, pressed against the cell membrane
Is cardiac muscle striated
Yes
Where is the nuclei in cardiac muscle
In the centre of the cell
Which muscles have intercalated discs
Cardiac muscle
What do indicated discs do
Connect adjacent myocytes chemically and mechanically
Which muscles are branching
Cardiac muscles
What shape are smooth muscles longitudinally
Spindle-shaped
Is Smooth muscle striated
No
What are the contractile cells around capillaries
Pericytes
What sells contract around glands
Myofibroblast and myoepithelial cells
What is a Syncytium?
Myoblasts fused to form multi cellular muscle fibre
How are myofibrils formed
Sarcomeres a joined end to end
What are fascicles
Muscle fibres grouped together
Why are skeletal muscles multinucleated
They are formed from the fusion of multiple individual myoblasts
What is the difference between cardiac and skeletal muscle
Cardiac muscle branches and has intercalated discs
Skeletal muscle is multinucleated
What is the thin filament of a sarcomere
Actin
What is a sarcomere
Functional unit of muscle
What is the thick filament in a sarcomere
Myosin
What are the limits of a sarcomere
Between 2 Z-lines
What are the two types of skeletal muscle
Slow twitch and fast twitch
What is the histological difference between type one and two skeletal muscle
You can’t tell them apart on h&e stains
How do you type one fibres derive energy
Through oxidative phosphorylation
Which fibres are fatigue resistant
Type one slow twitch fibres
Which fibres are not fatigue resistant
Type two fibres that get energy from glycolysis alone
What senses tension in a muscle
Muscle spindles
What are muscle spindles
Intrafusal muscle fibres wrapped around by gamma efferent nerve fibres
What is the order of connective tissue from small to large in skeletal muscle
Endomysium
Perimysium
Epimysium
What connective tissue is between individual muscle fibres
Endomysium
What is perimycium
Connective tissue that binds groups of muscles together to form fascicles
What binds muscle fascicles together
Epimysium
What are sharpey’s fibres
Connect muscle to bone
What connective tissues to sharpey’s fibres link
They connect epimysium of muscles to the periosteum of bone
