13.9 Voluntry And Involuntry Muscles Flashcards
What is syncitium?
A multinucleated cell
What is the plasma membrane surrounding a skeletal muscle cell called?
Sarcolemma
What are the three types of muscle?
Skeletal
Cardiac
Involuntary
Which types of muscle are striated?
Skeletal
Cardiac (specialised striated)
Which types of muscle are involuntary?
Cardiac
Involuntary
Describe the arrangement of skeletal muscles, and what this does.
Regular so the muscle contracts in one direction.
Kind of in lines.
Describe the arrangement of cardiac muscles, and what this does.
Cells branch and interconnect, resulting in simultaneous contraction.
Describe the arrangement of involuntary muscles, and what this does.
No regular arrangement, so cells can contract in different directions.
Describe the contraction speeds of the three muscle types.
Skeletal- short
Cardiac- intermediate
Involuntary- (relatively) long time
Which muscle type is multinucleated?
Skeletal
What does uninucleated mean?
Only one nucleus in each cell.
Why are skeletal muscle fibres longer than normal cells?
Individual embryonic muscle cells fused together, to form them, these share cytoplasm.
What is the cytoplasm in skeletal muscle cells called?
Sarcoplasm
What does the sarcoplasmic reticulum contain, in skeletal muscle fibres?
Calcium ions- these are required in muscle contraction.
What are skeletal muscles made up of?
Bundles of muscle fibres, which are made of myofibrils.
