Muscle Tissue Flashcards
What is muscle tissue specialised for?
The conversion of chemical energy into mechanical energy
What type of muscle is striated and voluntary?
Skeletal muscle
Is skeletal muscle:
- Striated or non-striated
- Involuntary or voluntary
Striated and voluntary
What type of muscle is striated and involuntary?
Cardiac muscle
What type of muscle is non-striated and involuntary?
Smooth muscle
Is smooth muscle:
- Striated or non-striated
- Involuntary or voluntary
Non-striated and involuntary
What part of the NS controls skeletal muscle?
Somatic
What part of the NS controls smooth muscle?
Autonomic
What is the function of skeletal muscle?
The voluntary movement of the skeleton, eyes, and tongue
How are the nuclei arranged in skeletal muscle?
Multiple nuclei located peripherally
Arrangement of what causes a striated apperance?
Myofibrils
What are myofibrils composed of?
Repeating units called myofilaments
What are dark and thick myofilaments:
myosin or actin?
Myosin
What are light and thin myofilaments:
myosin or actin?
Actin
What divide myofibrils into contractile units?
What are these contractile units called?
Z lines.
Sarcomeres.
What is the thin layer that separates each myofibril?
Sarcoplasm
What is skeletal muscle specialised for?
Contraction and relaxation
What are individual muscle fibres separated by?
Endomysium
What does the endomysium do?
Separates individual muscle fibres
What are bundles of muscle fibres grouped into?
Fasciculi
What is the loose connective tissue that surrounds each fascicule?
Perimysium
What is epimysium?
Dense connective tissue that surrounds the entire external surface of the muscle
What is the dense connective tissue that surrounds the entire external surface of the muscle?
Epimysium
What is the specialised plasma membrane that envelops the external surface of skeletal muscle?
Sarcolemma
What sit between myofibrils?
Multiple mitochondria
What innervates skeletal muscle?
Somatic motor neurons
What is a motor unit?
A single motor neurone and all of the muscle fibres it innervates
What is neuronal action potential converted to during muscle contraction?
Chemical messenger acetylcholine
What is the sarcoplasmic reticulum?
A network of tubules that wrap around myofibrils
What are the three layers of the heart wall?
Pericardium - outer tissue layer
Myocardium - cardiac muscle tissue
Endocardium - single layer of endothelial cells
Where is smooth muscle found?
Lining hollow organs
What is smooth muscle specialised for?
Continuous contractions
What is the structure of smooth muscle cells?
Small, spindle shaped cells with tapered ends.
What structural unit isn’t present in smooth muscle and what does mean for its appearance?
Sarcomeres aren’t present.
Means smooth muscle isn’t striated.
What anchors smooth muscle cells to the cytoplasm and cell membrane?
Focal densities
