A & P 1 Lab

Muscular system

Skeletal muscle

2 characteristics = voluntary and multinucleated

Dense regular = connective tissue

Location is tendons and ligaments

Neuromuscular junction = synapse between nerve and muscle

Skeletal muscle

Muscle cell

1. Motor neuron

2. Synaptic vesicles w/ Ach

3. Sacrolemma = muscle membrane

1. Sacroplasmic reticulum (S.R) w/ Ca2t

2. Transverse tubules

1. Myosin (dark red)

2. Actin (light red)

1. Orbicularis oculi: action= close eye

2. Orbicularis oris: action= close mouth

3. Sternocleidomastoid: action= flex head and inserts on mastoid process

1. Temporalis

2. Masseter: action = chewing

3. Zygomaticus: action= smiling

1. Serratus anterior

1. Splenius : extends the head

2. Levator scapula : elevates the scapula

3. Rhomboids

1. Trapezius

2. Lattimus dorsi

1. Perctoralis major (superficial)

2. Perctoralis minor (deep)

3. Rectus abdominis: inserts at the xiphoid process

1. External obliques (superficial) = rotates torso

2. Internal obliques (deep) = rotates torso

1. Deltoid : insertion = deltoid tuberoisty

2. Tricep brachii

3. Bicep brachii

4. Brachialis

1. Hand flexor (group) = flex hand

2. Hand extensors (group) = extend hand

2. Gluteus Maximus

1. Tensor facisa latae: abduct thigh

1. Adductor magnus: adduct thigh

1. Gastrocnemis: insertion: calcaneous