Anatomy Part #1

(Neuromuscular Junction)(Major Muscle)(Skeletal Muscle)

Muscle fiber (red)

Muscle fiber (red)

elongated multi nucleate cell; has a banded (striated) appearance

Endomysium (between fibers) #6

Individual muscle fiber is surrounded by a fine sheath of connective tissue consisting of areolar and reticular fibers.

Fascicle (purple)

bundle of muscle cells, segregated from the rest of the muscle by a connective tissue sheath (perimysium)

Perimysium #2

Surrounding each fascicle is a layer of fibrous connective tissue

Epimysium #3

An “overcoat“ of dense irregular connective tissue surrounds the whole muscle.

epi-

outside

-mysium

muscle

peri-

around

What is this muscle?

Temporalis

What is purple muscle called?

Orbicularis Oculi

What is the blue muscle called?

Zygomaticus

What is the green muscle called?

Orbicularis Oris

What is #5 muscle called?

Epicranius, frontal belly

What is #6 muscle called?

Masseter

#7?

Sternocleidomastoid

What is #8?

Pectoralis Major

What is #9?

Deltoid

What is #10?

Biceps Brachii

What is #11?

Rectus abdominis

What is #12?

Internal oblique

What is #13?

Adductor Longus

What is #14?

Gracilis

What is #15?

Sartorius

What is #16?

Tiblias Anterior

What is #17?

Gastrocnemius

What is #18?

external oblique

What is #19?

Tensor Fasciae latae

What is #20?

Rectus Femoris

What is #21?

Vastus Lateralis

What is #22?

Vastus medialis

1st Event at the NMJ?

AP travels the link down the neuron to the axon terminal.

NMJ Step 2:

Voltage-gated calcium channels open and calcium ions diffuse into the terminal.

NMJ Step 3:

Calcium entry causes synaptic vesicles to release acetylcholine via exocytosis

NMJ Step 4:

AcH diffuses across the synaptic cleft and vines to the AcH receptors which contain Ligand-gated cation channels

NMJ Step 5:

These ligand-gated cation channels open

NMJ Step 6:

Sodium ions enter the muscle fiber potassium ions exit the muscle fiber. The greater end of flux causes the membrane potential to become less negative.

NMJ Step 7:

Once the membrane potential reaches its threshold value an Action potential (AP )propagates against the sarcolemma

Neuromuscular Junction

area where the axon terminal of a motor neuron meets a motor end plate of a muscle fiber

#1?

Triceps Brachii

#2?

Brachialis

#3?

Brachioradialis

#4?

Extensor carpi radialis longus

#5?

Flexor carpi ulnaris

#6?

Extensor carpi ulnaris

#7?

Extensor digitorum

#8?

Iliotibial tract

#9?

Gastrocnemius

#10?

Soleus

#11?

Fibularis Longus

# 12?

Calcaneal (Achilles Tendon)

#13?

Epicranius, occipital belly

#14?

Sternocleidomastoid

# 15?

Trapezius

#16 ?

Deltoid

#17?

Infraspinatus

#18?

Teres Major

#19?

Rhomboid Major

#20?

Latissimus Dorsi

#21

Gluteus Medius

#22?

Gluteus Maximus

#23?

Adductor magnus

#24?

Biceps Femoris

#25

Semitendinosus

#26?

Semimembraneous