Emily Nguyen Chapter 6 Mythology

How many muscles are in the body?

650

What are the two general characteristics of muscles?

Excitability and Contractility

What does excitability mean?

generates electrical impulses

What does Contractility mean? 

to shorten in length 

What are the only two cells in the body that exhibit excitability?

muscle and nerve cells

What are the three functions of the muscles?

Voluntary Movement, Maintain Body Posture, and Heat production

What is the tendon of origin commonly called?

head or ceps

What does the tendon of origin connect to?

less moveable structures

What is the tendon of insertion commonly called?

tail

What does the tendon of insertion connect to?

the more moving structure 

What are the three layers of fascia?

Epimysium, perimysium, and endomysium

What does a somatic motor unit consist of?

somatic motor neurons plus all the muslce fibers it stimulates

What are proprioceptors?

a sensory receptor which receives stimuli from within the body, especially the ones that respond to position or movement

What is a agonist?

muscle that causes a desired action

What is a synergistic muscle?

muscle that acts with the agonist

What is an antagonist muscle?

muscle that move the opposite direction of the agonist

What is a fixator or stabilizer

muscle that stabilizes body position and decreases unnecessary movement

What are the characterisitics of muscles that are used in maximal training? 

large diameter msucle fibers, fast rate of contraction, and high power development

What are the characterisitics of muscle used in sub-maximal training?

high myoglobin content, darker colored cells

What is muscle agenesis?

absence or underdevelopment of muscle tissue

What is a hernia? 

the bulging of an internal organ or tissue through a weak spot or hole in the surrounding muscle or tissue

What are some factors that cause hernias?

heavy lifting, chronic coughing or sneezing, obesity, pregnancy, and prior surgery

What is the Valsalva maneuver?

a forceful breathing technique where you exhale forcefully against a closed airway

Define hypertrophy

enlargement of a organ from its increase of size of its cells

Define atrophy

wasting away or shrinking of a body part, tissue, or organ due to lack of use, disease, or injury

What is myositis?

inflammation or swelling of the muscles due to injury, infection, certain medication, or autoimmune disorders

How do you treat myositis?

Medications (corticosteriods and other immunosuppressants) to reduce inflammation and physical therapy to restore muscle strength and function

What are muscle spasms?

involuntary and forceful contraction of a muscle group that can be painful and cause stiffness

What are cramps?

involuntary and painful tightening of a muscle and it can restrict fredom of movement

What is a clonus?

medical condition by involuntary, rthymic muscle contractions and relaxations that are triggered by stretching a muscle, most commonly seen in the ankle

What is tetanus?

a serious diease caused by a bacterium called Clostridium tetani, which enters the body through cuts or wounds

What are convulsions?

sudden, involuntary, and violent shaking of the body due to severe conditions and relaxation of other muscles, often caused by abnormal electrical activity in the brain

Where are smooth muscles located?

in the walls of hollow organs, blood vessles, and in systems inteh respiratory, urinary, reproductive, and digestive tracts as well as the skin and eyes

Frontalis

raises eyebrows; wrinkles forehead

Orbicularis oculi 

closes eyelids

Orbicularis oris

puckers the lips

Buccinator

compresses the cheeks, as when blowing

Phatysma

pulls lower lip and jaw downward

Zygomaticus

smiling (raises corners of mouth)

Superior Rectus

elevates eye

Inferior Rectus

depresses eye

Medial Rectus

rotates eye to the middle

Lateral Rectus

rotates eye to the sides

Temporalis

elevates mandible, and closes the jaw

Masseter

synergist with the temporals; elevates mandiable

Genioglossus

sticks out the tongue

Styloglossus

pulls the tongue in

What are the general characterisitics of facial muscles?

all are superficial, they insert into the overlying skin, developed from the branchial arches, and they all were provided nerve supply by the facial nerve

What nerves innervate the facial muscles?

the facial nerves

What is the action of the frontalis?

raises eyebrows; wrinkles forehead

What muscle closes the eyelids? 

Orbicularis oculi

What muscle is responsible for squinting, winking, blinking?

Orbicularis oculi

What muscle puckers the lips?

Orbicularis oris

What muscle compresses the cheeks?

Buccinator

what muscle pulls the lower lip downward?

Phatysma

What is Bell’s Palsy

paralysis of the facial nerves that lead to a asymmetry of the facial features

How many muscles move the eye?

six muscles

What muscles elevate the mandible?

Temporalis muscle and the masseter muscle

What nerves innervate the tongue?

Hypoglossal Nerve (XI)