Muscular System Karina Espinosa Per.7 (Names of Muscles (Zygomaticus (L:…
Muscular System Karina Espinosa Per.7
Major Functions of Muscular System
1: Gives us posture
2: Allows us to have movement
3: Thermogenesis = Heat production
Names of Muscles
Epicranius (L: Head)
Gastrocemius (L: Lower Leg)
Deltoid (L: Shoulder)
Gluteus Maximus (L: Butt)
Orbicularis (L: Eyes)
Llitibial Tract (L: Outer Thigh)
Rectus Abdominis (L: Abs)
Tensor Fascla (L: Hip)
Gracilis (L: Inner Thigh)
Soleus (L: Lower Leg)
Latissimus Dorsi (L: Back)
Zygomaticus (L: Upper Cheek)
Temporalis (L: Temples on Head)
Calceneal Tendon (L: Back of Foot)
Pectoralis Major (L: Chest)
Extensor Digitorum (L: Lower Arm)
Tríceps Brachili (L: Triceps)
Gluteus Medius (L: Upper Butt)
Splenius Capitis (L: Inner Neck)
Sternocleidomastoid (L: Outer Neck)
There are fourteen types of body movement including :
Flexion: Movement that decreases angle of joint
Extension: Movement that increases angle of joint
Hyperextension: Extension beyond 180º
Rotation: Movement of a bone around a longitudinal axis
Abduction: Movement of limb away from midline
Adduction: Movement of limb toward the midline
Circumduction: Proximal end of a limb is stationary and the distal end moves in a circle
Plantar Flexión: Pointing toe
Dorsiflexion: Lifting superior surface of foot towards shin
Inversion: Turn sole of foot medially
Eversion: Turn sole of foot laterally
Supination: Forearm rotates laterally so palm faces anterioly
Pronation: Forearm rotates medially so palm faces posterioly
Oppisition: Movement of thumb to touch tips of other fingers
3 Muscle Tissues and their Functions
They form the heart’s walls and it allows blood to circulate around the heart.
This muscle controls movements inside internal organs. For example, digestive tracts, blood vessels urinary and reproductive organs.
It is subject to conscious control and it makes up approximately 40-50% of body weight.
Structure and Organizational Levels of Skeletal Muscle
Connective Tissue Coverings
LAYERS: Fasicles, aponeuroses, epimysium, perimysium, muscle cell/ fiber, endomysium.
Skeletal Muscle Fibers
Sacrolemma, sacroplasm (Contains- Glycogen, myogloulin, parallel myofibrils (made up of myofilaments), Z line, I bands, A bands, H zoneM line.
Sacroplasmic Reticulum is associated with transverse. T- tubules penetrate into muscle fiber.
Synapse, neurotransmitters, motor end plate, synaptic vesicles, synaptic cleft.
Muscle Contraction (Sliding Filament Theory)
1) The nerve impulse travels down the sacrolemma and into the T-tubules. It causes sacroplasmic rectilium to release Ca++ into the sacrolasm.
2) Ca++ binds to actin myofilaments which exposes the myosin binding site.
3) The myosin head attaches to the actin, forming actin/ myosin crossbridges.
4) The myosin head moves towards the M line of sacromere, pulling actin filaments past myosin.
5) That process is repeated many times and it is powered by ATP.
6) Z lines get closer together as actin and myosin filaments slide past each other, and sacromeres shorten. This shortens the entire myofibril.