Chapter 10

muscle tissue and organization

Excitability

Stimuli initiates electrical changes in the muscle fiber

contractility

A stimulation of muscle fibers lead to contraction/shortening of fibers

Elasticity

The muscle fiber is able to return to its orginal length

Extensibility

The ability of muscle fibers to stretch beyond its relaxed length

Somatic

Voluntary control

Fascicles are

Muscle fibers in bundles

Muscle fibers contain

Myofibrils

Myofibrils are composed of

Myofiliaments

Myofiliments

two proteins

Epimyisum

surrounds entire muscle

perimyisum

surrounds individual fascicles

Endomysium

inner most layer, surrounds and insulates each muscle fiber

Aponeurosis

Flat tendons 

The point of attachment that doesn’t move

Origin

The point of attachment that does move

Insertion

Sarcolemma

Plasma membrane

Sarcolemma characteristic

Semipermable

Sarcoplasma

cytoplasma

Cytoplasma contains

Glycogen, myoglobin and oxygen

T Tubules

Store calcium for muscle contraction

Cisternae (terminal)

Blind sacs at the end of the Sarcoplasmic Reticulum

Tropomyosin

sets over active site

Troponin

Sets on top of tropomyosin and actin

Light bands

I Bands

What do I bands do?

Contain only thin filaments and titin

titin

Enables resting postion

Dark bands

A bands

Z line

disc

M line

Alignment with the A band

Synaptic Knob

Expanded end and surface area of a neuron

Synaptic vesicles

Sacs filled with ach(nuero transmitter)

Motor end plate

Region on the sarcolemma to increase surface area

Synaptic cleft

Narrow space separating the synaptic knob from the motor end plate 

Ach receptors 

In the motor end plate that bind ach 

ACh E

An enzyme in the synaptic cleft that decomposes ach 

Isotonic 

Muscle tension equals or is great than resistance
the Muscle shortens

Isometric

Muscle doesnt shorten

No movement