Chapter 1 Flashcards
How mobile are fibrous joints?
Immobile
How mobile are cartilaginous joints?
Limtied
How mobile are synovial joints?
Considerably mobile
What type of cartilage is found at joint articulations?
Hyaline
What are fasciculi?
Bundles of ~150 muscle fibers, covered by perimysium
What connective tissue covers invidual muscle fibers?
Endomysium
What is a sarcolemma?
Muscle fiber membrane, contiguous with muscle fiber itself.
What is a motor unit?`
A motor neuron and all of the muscle fibers that it innervates.
What is the M Bridge?
Center of sarcomere. Where Myosin is anchored.
What are the Z lines?
Ends of sarcomere, where the actin anchors.
What is the arrangement of actin and myosin?
Each actin has 3 myosin around it, each myosin has 6 actins around it.
What is the A band?
Area with myosin, goes from M bridge to I zone
What is the H zone?
Center of the sarcomere where only myosin exists, no overlap with actin
What is the I zone?
Periphery of sarcomere where only actin is, no overlap with myosin.
Which parts of the sarcomere shrink when contraction occurs?
H and I zones.
What is the sarcoplasmic reticulum?
Series of tubules that release calcium from vessicles at Z lines to stimulate a contraction.