Anatomy
This layer surrounds an entire muscle.
What is the epimysium?
This ability allows muscle tissue to respond to a stimulus.
What is excitability?
This is the functional contractile unit of the myofibril
What is the sarcomere?
The nervous system sends this electrical signal to trigger contraction.
What is an action potential?
This type of muscle is attached to bones and allows voluntary movement.
What is skeletal muscle?
Each muscle fiber bundle is surrounded by this connective tissue.
What is the perimysium?
This property allows muscles to shorten and exert tension.
What is contractility?
This sarcomere structure marks the boundary of each sarcomere
What are Z disks?
This structure receives the action potential and passes it into the muscle fiber.
What is the sarcolemma?
This muscle type is found only in the heart and is responsible for pumping blood.
What is cardiac muscle?
This organelle stores and releases calcium in muscle fibers.
What is the sarcoplasmic reticulum (SR)?
This describes the ability of muscle to return to original length after contraction.
What is elasticity?
This region contains only thin filaments
What is the I band?
This tubular structure distributes the electrical signal to the myofibrils.
What are T-tubules?
This type of muscle lines internal organs and moves substances involuntarily.
What is smooth muscle?
These tiny units make up muscle fibers and are surrounded by the SR.
What are myofibrils?
This ability enables muscle to contract even when stretched.
What is extensibility?
This region of the sarcomere contains thick filaments only and lies in the center
What is the H zone?
These two receptors in the T-tubule/SR complex are critical for calcium release.
What are DHPR and RYR1?
These two muscle types are striated because of their organized contractile fibers.
What are skeletal and cardiac muscles?
This contractile unit contains actin, myosin, Z-disks, and other bands.
What is a sarcomere?
Approximately this many muscles are found in the human body.
What is 600?
This structure forms the attachment site for thick filaments
What is the M line?
Calcium binds to this protein, causing tropomyosin to expose actin’s active sites.
What is troponin?
All three muscle types rely on these two components for contraction.
What are calcium signals and myosin?