A&P101 Lecture 16 Quiz Sarcomere structure

A

I Band

B

A- Band

C

Myosin

D

Actin

E

Z-Line

F

Titin

G

M -Line

H

H- Band

What is the sarcolemma?

plasma membrane of the Muscle cell.

What is the T-tubule?

extension of the sarcolemma

Which organelle in the sarcoplasm is functionally linked to the T-tubule?

Sarcoplasmic Reticulum

What is another function of the Organelle in part C ?

Calcium storage.

Please name the Gross Anatomy sections for A, B, and, C

A) Muscle B) Facicles C) Fiber

Please name the connective tissue covering for A , B, and, C

A)  Epimysium   B) Perimysium   C) Endomysium

If someone has no actin, how would this affect a persons muscles ability to contract. AND WHY ?

No contraction because Myosin can't be Pulled on anything.

What is rigor mortis? Please explain the mechanism of this the same way Prof. Joe discussed it.

Its a Post-death muscle stiffening caused by lack of ATP.

Explain (or draw out ) the concept of stretching/ flexibility in relation to protein filament.

A - extreme shortening (over lap)

B - No overlap ( Extreme Lengthening)

C - Perfect, Little Overlap

Why is ATP needed for muscle contraction? Please have a detailed explanation.

crossbridge detachment.

ATP breaks crossbridge to allow contraction cycle to continue.

Why is calcium needed for muscle contraction? Please have a detailed explanation.

Calcium is the key.

The Key Hole is troponin and

The Door is actin.

Calcium binds to troponin.

What is the name of the cell that interacts with a muscle fiber to initiate muscle action potentials?

Motor neurons.

What chemical does cell A ( motor neuron) send to the muscle fiber to initiate muscle action potentials?

ACH

Where does the muscle action potential travel to?

T-tubule

How does the muscle action potential cause calcium release? ( Provide 2 key details for this question)

It travels through T-tubules, causing protein changes that OPEN RyR receptors in the SR. The SR releases calcium( DHP to RYR)