Muscle Contraction Guided Notes

Muscle Contraction Guided Notes

Name: ______Class: ______

Do Now:

1)  The connective tissue covering that encloses the sarcolemma of an individual muscle fiber is called the

a)  Epimysium

b)  Perimysium

c)  Endomysium

d)  periosteum

2) A fascicle is

a)  A muscle

b)  A bundle of muscle fibers

c)  A bundle of myofibrils

d)  A group of myofilaments

3) Muscle tissue that is involuntary

a)  cardiac muscle only

b)  Smooth muscle only

c)  Skeletal muscle only

d)  Cardiac and smooth muscle

e)  Cardiac and skeletal muscle

4) The muscle tissue that consists of single, very long, cylindrical, multinucleate cells with very obvious striations is:

a)  cardiac muscle only

b)  Smooth muscle only

c)  Skeletal muscle only

d)  Cardiac and smooth muscle

e)  Cardiac and skeletal muscle

5) Which of the following is NOT a function of the muscular system

a)  Producing movement

b)  Maintaining posture

c)  Stabilizing joints

d)  Generating heat

e)  hematopoiesis

Muscle Structure

Muscle à ______(bundle of fibers) à ______(single cell) à ______à ______(unit of contraction)

Microscope Anatomy of Skeletal Muscle

Use the picture to come up with a definition of the following:

I band

A band

H zone

Turn and Talk

First match the words …

actin cell

myofibril group of cells

sarcomere cell membrane

fascicle protein

muscle fiber organelle

sarcolemma contractile unit

Then, write a paragraph that uses all the words in both columns above and explains that structure of the muscle

Contraction Overview

Contraction Details

1. A motor neuron stimulates the muscle cell by releasing the ______into the synaptic cleft between the neuron and muscle cell.

Note: A ______is a single motor neuron and all the muscle fibers it activates

2. ACh causes an electric current called an ______to move through the muscle cell.

3. The action potential causes the ______.

4. ______on actin filaments.

5. Myosin heads (& ADP) attach to actin binding sites, ______.

6.  Myosin heads release ADP, move the actin filament in “______”

7.  ATP binds to myosin head. The crosslink between actin and myosin breaks.

8.  ATP becomes ADP + P, readying the myosin head to reattach to actin.