Where is smooth muscle commonly found in the body: | walls of hollow organs, vessels, respiratory passageways |
Describe the typical smooth muscle cells/tissue physical characteristics: | cells are tapered at ends, branching networks, non-striated, SINGLE central nucleus |
Are SMOOTH muscle tissue voluntary or involuntary? | INVOLUNTARY |
What are some functions of smooth muscle: | produces peristalsis; contracts/relaxes slowly; may sustain contraction |
When does smooth muscle contracts (in response to?) | nerve impulse, HORMONAL stimulation, STRETCHING, other stimuli |
Where is CARDIAC MUSCLE commonly found in the body: | wall of heart |
What are some physical characteristics of CARDIAC muscle | branching interconnections special membranes between cells called intercalated discs, single nucleus, LIGHTLY STRIATED |
What is the CONTROL of CARDIAC muscle | INVOLUNTARY- self-excitable |
Whats the function of CARDIAC muscle | pumps blood out of heart, self-excitatory... influenced by nervous system and hormones |
What are some physical characteristics of SKELETAL MUSCLE | long, cylindrical, MULTI-NUCLEATED; HEAVILY striated |
Where are SKELETAL muscle typically found in the body? | attached to bones |
describe the control of skeletal muscle | VOLUNTARY- making up 40% of body weight; 600+ individual muscles (usually acting in groups) |
What are some functions of SKELETAL MUSCLE | produces movement at joints, stimulated by nervous system; contracts/relaxes RAPIDLY, maintain posture, heat generation |
What keeps the body upright/ maintaining posture? | Muscle tone: a steady partial contraction of muscle |
What are fascicles: | BUNDLES of MUSCLE cells (FIBERS) making up a whole "muscle" held by fibrous connective tissue |
Whats Endomysium: | DEEPEST layer of areolar connective tissue; surrounds INDIVIDUAL fibers WITHIN FASCICLES |
Whats Perimysium: | connective tissue later AROUND EACH FASCICLE |
Whats Epimysium | connective tissue sheath that ENCASES WHOLE MUSCLE; forms INNERMOST layer of DEEP FASCIA |
Whats DEEP FASCIA | tough fibrous connective tissue membrane that encloses/defines a muscle |
Successfully label diagram | compare answers |
This band of dense regular connective tissue ATTACHES MUSCLE to BONE | tendons |
impulses come from brain and stimulate muscle contractions; these neurons are called | MOTOR NEURONS |
These type of neurons carry sensation information from the periphery to the CNS | SENSORY NEURONS |
A SINGLE neuron and ALL the MUSCLE FIBERS IT STIMULATES is a ____ (small versions= stimulates fewer muscle fibers-> find movements) (LARGE versions= used for broad movements) | MOTOR UNIT |
On a cellular level what causes muscle cells/neurons to exhibit their "excitability" characteristic | CHANGE in MEMBRANE POTENTIAL- as ions enter/leave cell-> they create electric signals |
The "electricity" moving along the neuron thus calling the cell into action is call the____ (aka nerve impulses) | action potential |
(fill in the blank) ______ is the process of _____ developing into______ to form _________ | MYOGENESIS is the process of MYOBLASTS developing into MYOCYTES to form MUSCLES |
(Describe the 7 steps in neuromuscular junction) | ACTIN Potential travels length of AXON of motor neuron to AXON Terminal-> Charged regulated CALCIUM Channels (Ca+ ions diffuse into TERMINAL)-> entry of Ca+ ion triggers SYNAPTIC VESICLES to release ACETYLCHOLINE-> ACh travels across Synaptic Cleft BINDING to ACh receptors thus triggering channels-> LIGAND-GATED channels OPEN-> (greater flow) Sodium ions ENTER/ (lesser flow) Potassium ions EXIT muscle fiber-> DIFFERENCE in Na+/K+ enter/exit flows NEGATIVELY charges membrane potential-> when membrane potential reaches THRESHOLD value causes action potential propagate along sarcolemma |
What are the 3 main properties of muscle | Contractility- ability to forcefully SHORTEN; muscles can ONLY PULL/never push
Excitability- ability to RESPONSE to STIMULI; delivered from motor neuron/hormone
Extensibility- ability to be STRETCHED |
What's the 2 types of protein found in muscles that make CONTRACTILITY possible | Actin-thin, light filaments
Myosin- thick, dark filaments
*both present in alternating bundles w/in myocytes*
both overlap where they meet |
What's the sarcomere; and what does it do? | contracting subunit of skeletal muscle (contains myosin and actin); ATP triggers the power to cause these filaments to slide together causing CONTRACTION (think myosin [center cord] pulling actin together [peripheral cords]) |
What are some energy sources for muscle contraction? | Muscle requires energy in form of ATP; skeletal muscle prefers to produce ATP via aerobic metabolism-> requiring 02, Glucose |
Muscle cells store small supply of different resources for rapid ATP generation, such as during vigorous exercise. List 3 storage types/locations: | MYOGLOBIN- stores 02; GLYCOGEN- storage form of glucose; FATTY ACIDS- stored as triglycerides formed into fat droplets |
During STRENUOUS activity muscle cells use ________ which doesn't require oxygen | ANAEROBIC ATP METABOLISM- lactic acid accumulation, excess post-exercise 02 consumption (lactic acid removed/energy stores replenish with rapid breathing to take in extra 02) |
FACTS about Muscle Fatigue: actually tire because_____ is unaccustomed to hard work. Rather, muscles tiring due to ATP depletion, lactic acid accumulation. | NERVOUS system find it unpleasant |
List effects of exercise: | ^balance/joint flexibility, ^hypertrophy, ^myo-tissue, vasodilation, strengthened heart muscle, ^breathing/resp efficiency, weight control, stronger bones, better mood |
Creatine Kinase (CK) aka creatine phosphokinase (CPK): 3 types of isoenzymes CK-BB: found in nervous/skeletal muscle tissue; CK-MM: mostly in skeletal muscle; CK-MB: mostly in cardiac muscle. Increase in these isoenzymes indicates? | CK-BB: stroke? ALS? CK-MM: MS or myositis. CK-MB: cardiac muscle damage like MI |
Anabolic Steroid Use: normally RX-> promote muscle regeneration/prevent atrophy from disuse after surgx... | can be used ILLEGALLY to enhance athletic performance (need large doses, cause SERIOUS side effects) |
List Major side effects of Anabolic Steroids: | ^cholesterol-> atherosclerosis, heart/renal failure, stroke. Liver damage-> susceptible to cancers. Suppress immune system-> ^ risk of infection/cancer. Risk for baldness |
Side Effects of Anabolic Steroids in MEN | impotence, testicular atrophy, low sperm count/infertility, gynecomastia, mood swings, depression, violence |
Side Effects of Anabolic Steroids in WOMEN | disrupt ovulation/menstruation, male characteristics: breast atrophy, enlargement of clitoris, ^body hair, deepening of voice, baldness, severe acne |
Define muscle "tone".... What happens when muscles aren't used | a relaxed muscle in a partially contracted state; become weak, flabby, and lacking in tone |
define ISOTONIC contraction | taking place w/NORMAL contraction... TONE/TENSION w/in muscle remains SAME... muscle LENGTH changes |
define ISOMETRIC contraction | relating to or denoting muscular action in which tension is developed WITHOUT contraction of the muscle... no change in muscle length, GREAT ^ in muscle tension: PUSHING AGAINST IMMOVABLE FORCE.. **most body movements involve combo of isotonic/metric contractions |
What are the 2 forms of isotonic contractions; describe them: | CONCENTRIC: produce obvious change in position as muscle SHORTENS
ECCENTRIC: muscle LENGTHENS as it EXERTS FORCE |
Tendons attach muscles to bones.... Origin: attached to more____ part of skeleton; Insertion: attached to more____ part of skeleton | origin-> FIXED; insertion-> MOVABLE |
Muscles work in pairs/groups.
Agonist: ______ to do the _______
Antagonist: _____ when the agonist is _______
Synergists: _______ in movement and _____ body parts | Agonist: CONTRACT to do the MOVEMENT
Antagonist: RELAX when the agonist is contracting
Synergist: ASSIST in movement and STEADY body part |
List 3 different Lever Systems | Lever: bone
Fulcrum: joint
Force: applied by muscle |
First Class Levers: fulcrum located between the _____ and the _____ (think seesaw) | fulcrum located between the RESISTANCE and the EFFORT |
Second Class Levers: resistance located between the _____ and ______ | resistance located between FULCRUM and EFFORT |
Third Class Levers: ***most body systems*** effort located between____ and _____ | effort located between the RESISTANCE and FULCRUM |
What are the major characteristics considered for muscle taxonomy? | Location, Size, Shape, Direction, Number of heads, Action
Location: ex-> Temporalis (near skull's temple)
Size: Gluteus maximus (largest in that area)
Shape: Serratus anterior (serrated edge)
Direction: External oblique (runs obliquely)
#of Heads: Biceps brachii (2 heads)
Action: Flexor digitorum (flexes toes) |
HEAD/NECK MUSCLES:
Location/Function: Oricularis oculi | L: encircles eyelid F: closes eye |
HEAD/NECK MUSCLES:
Location/Function: Orbicularis oris | L: encircles mouth F: closes lips |
HEAD/NECK MUSCLES:
Location/Function: Buccinator | L: Fleshy part of cheek F: flattens cheek, helps-> eating, whistling, blowing wind instruments |
HEAD/NECK MUSCLES:
Location/Function: Temporalis | L: above/near ear. F: closes jaw |
HEAD/NECK MUSCLES:
Location/Function: Masseter | L: at angle of jaw F: closes jaw |
HEAD/NECK MUSCLES:
Location/Function: Sternocleidomastoid | L: along lateral neck, to mastoid process F: flexes head; rotates head toward opposite side from muscle |
SHOULDER/ARM MUSCLES:
Location/Function: Trapezius | L: posterior neck/upper back to clavicle & scapula F: raises shoulder pulls it back; superior portion extends and turns head |
SHOULDER/ARM MUSCLES:
Location/Function: Deltoid | L: covers shoulder joint, to lateral humerus F: abducts arm, flexes and extends arm |
SHOULDER/ARM MUSCLES:
Location/Function: Pectoralis major | L: superior, anterior chest, to humerus. F: flexes and adducts arm |
FOREARM/HAND MUSCLES:
Location/Function: Biceps brachii | L: anterior arm along humerus to radius F: flexes forearm; supinates forearm and hand |
FOREARM/HAND MUSCLES:
Location/Function: Triceps brachii | L: posterior arm, to ulna F: extends forearm |
FOREARM/HAND MUSCLES:
Location/Function: Brachialis | L: deep to biceps brachii; inserts at anterior elbow joint F: forceful flexor of forearm |
FOREARM/HAND MUSCLES:
Location/Function: Flexors (carpi, digitorum groups) /extensors (carpi, digitorum groups) | FCG-> L: ANTERIOR forearm to HAND F: flexes HAND
FDG-> L: ANTERIOR forearm to FINGERS. F: flexes FINGERS
ECG-> L: POSTERIOR forearm to HAND: F: extends HAND
EDG-> L: POSTERIOR forearm to FINGERS F: extends FINGERS |
SHOULDER/ARM MUSCLES:
Location/Function: Latissimus dorsi | L: Middle/lower back to humerus. F: extends and adducts arm |
TRUNK MUSCLES:
Location/Function: Diaphragm | L: dome-shaped partition between thoracic & abdominal cavities from top to bottom |
TRUNK MUSCLES:
Location/Function: Intercostals | L: between ribs F: elevate ribs and enlarge thoracic cavity |
TRUNK/ ABDOMINAL WALL MUSCLES:
Location/Function: External/ Internal Obliques/ Rectus abdominus | EO/IO -> L: anterolateral abdominal wall F: compress abdominal cavity and expel substances from body; flex spinal column |
LEG/THIGH MUSCLES:
Location/Function: Gluteus maximus | L: superficial buttock, to femur F: extends thigh |
LEG/THIGH MUSCLES:
Location/Function: Gluteus medius | L: deep buttock, to femur F: abducts thigh |
LEG/THIGH MUSCLES:
Location/Function: Iliopsoas | F: crosses anterior hip joint, to femur. F: flexes thigh |
LEG/THIGH MUSCLES:
Location/Function: Sartorius | L: crosses anterior thigh from ilium to medial tibia F: flexes thigh and leg (to sit cross-legged) |
LEG/THIGH MUSCLES:
Location/Function: Quadriceps (rectus femoris, vastus/medialis/lateralis/intermedius) | L: anterior thigh to tibia F: extends leg |
LEG/THIGH MUSCLES:
Location/Function: Hamstrings (bicep femori, semimembranosus, semitendinosus) | L: posterior thigh; ischium and femur to tibia and fibula F: flexes leg at knee, extends and rotates thigh at hip |
LEG/THIGH MUSCLES:
Location/Function: Vastus lateralis | L: anterior thigh, to tibia F: extends leg ***really important for giving IM shot to neonates/infants*** |
FOOT MUSCLES:
Location/Function: Gastrocnemius. (SITS ON TOP) | L: posterior leg to calcaneus, inserting by the achilles tendon F: plantar flexes foot |
FOOT MUSCLES:
Location/Function: Soleus. (SITS UNDERNEATH GASTROCNEMIUS) | L: posterior leg deep to gastrocnemius F: plantar flexes foot |
TRUNK MUSCLES:
Location/Function: Levator ani | L: pelvic floor F: aids defecation |
quadr/i means | four; ex: there are four quadrants in the abdomen |
Aero- means | air, gas; ex: aerobic organisms need air to survive |
-lysis. means | break down, dissolve; ex: surgeon performed a lysis of the adhesions |
endo. means | within; ex: she has an endoscope done on her knee |
Peri. means | around; ex: she lost control of the perirectal muscles |
Epi means | above; ex: he has pain in his epigastric area |
Iso- means | same, equal; ex: the fluid is isotonic- so cells won't shrink |
Syn- means | with, together; ex: the neuron joins another cell at the synapse |
brachi/o. means | arm; ex: brachial pulse is in the arm |
My/o. means | muscle; the wall of the heart is the myocardium |
Sarc/o. means | flesh; ex: she has a sarcoma behind her knee |
Troph/o. means | nutrition, nuture; ex: exercise can hypertrophy muscles |