A&P Quiz 3/Test 3 Muscle Tissue

Step three of sliding filament theory

Pivoting of myosin head Power stroke = ADP + P used to pivot

pivot joint

rotation only C1/C2 joint no motion monaxial

ball and socket joint

round head in a cup-shaped depression triaxial

herniated disk

rupture of the intervertebral disk cartilage, which allows the contents to protrude through it, putting pressure on the spinal nerve roots

Synarthrosis

immovable joint

suture joint

immovable joint, such as between the bones of the skull Bound by dense fibrous connective tissue

humeroulnar joints

largest strongest joint at elbow between trochlea of humerus and trochlear of ulna limited movement

Sagittal

left to right takng a bow mediolateral axis

ligaments of synovial joints

support and strengthen joints sprain-ligament with torn collagen fibers

Muscles of the rotator cuff (SITS)

supraspinatus, infraspinatus, teres minor, subscapularis

Cardiac muscle striations

Assembled just like skeletal muscles

Muscles store a lot of what besides protein?

Glycogen for energy

Why are intercalated discs important

Heart has to contract in a very specific way to pump blood. Communication between cells (myocytes) is important for this.

Step five of sliding filament theory

Hydrolysis of ATP making ADP + P Resets myosin head Myosin reactivation

Amphiarthrosis structure

More moveable than a synarthrosis Stronger than a diartrosis May be fibrous or cartilaginous

Step two of sliding filament theory

Myosin binds to active site Cross-bridge formation

intracellular fibers that make up muscle fiber

-myofibril -inside cell -surrounded by Sarcoplasmic Reticulum -contains sarcomeres

Tropomyosin-Troponin complex

-Tropomyosin strand attaches to active site -Troponin sits on top of Tropomyosin strand -reveals active site when Ca released from sarcoplasmic reticulum

triad

-1 T (transverse) tubules -2 terminal cisternae

At peak activity most ATP is produced through what process?

-2/3 of ATP from glycolysis anaerobic activity -1/3 of ATP from mitochondria aerobic activity

2 Methods to produce ATP for muscles

-Aerobic metabolism happens in mitochondria, oxygen available, yields 34 ATP -Anaerobic metabolism (fermentation), no oxygen, yields 2 ATP, and lactic acid

Intercalated discs

-Between myocytes -Allows communication between cardiac muscle cells

Cardiac muscles are similar to skeletal muscle except for:

-Cardiac myocytes (muscle cells) are branched -Mononucleated (one nucleus) -Contain intercalated discs -Gap Junctions, desmosomes -Intracellular cement -Nuclei in center -Functions like a single fused mass of cells -Contraction regulated by pacemaker cells, not voluntary nerves

3 layers of connective tissue membranes that are in muscles

-Epimysium -Perimysium -Endomysium

Relative Position

-Exernus/Superficialis = Visible at body surface -Internus (Profundus) = deep muscles -Extrinsic muscles = outside an organ -Intrinsic muscles = inside an organ

Action/Movement

-Flexor -Extensor -Retractor

What molecules are catabolized to create ATP at moderate activity in muscles?

-Glucose and Fatty acids -Glucose broken down by glycolysis from stored glycogen in muscles

Muscles are named in 5 ways

-Location: body region -Origin and insertion: first part origin, second part insertion -Fascicle organization -Relative position -Structural Characteristics

Size

-Longus - Long -Longissimus - Longest -Teres - Long and Round -Brevis - Short -Magnus - Large -Major - Larger -Maximus - Largest -Minor - Small -Minimus - Smallest

Structural Characteristics

-Number of tendons -Shape -Size -Action/movement

Rigor Mortis process

-Onset from 10 minutes to several hours -Happens in smallest muscles (facial) first -Lasts 1-3 days -At death membranes of muscle cell are more permeable to Ca -Once ATP is consumed myosin heads can't reset and muscles lock in place -End of rigor is due to cellular decay esp leaking of lysosomal enzymes

Fascicle organization

-Rectus = straight -Transverse = across -Oblique = angle

sarcoplasmic reticulum

-Similar to smooth endoplasmic reticulum wraps around myofibrils -Forms chambers (terminal cisternae) that attach to T (transverse) tubules.

skeletal muscles contain

-Skeletal muscle tissue (primarily) -Connective tissues -Blood vessels-carrying O2 & glucose out Water -Nerves

Perimysium

-Surrounds bundles (fascicles), blood vessels, and nerves that supply the fascicles

Endomysium

-Surrounds individual muscle cells (myocytes) -contains satellite cells (stem cells) that repair damaged muscle

Shape

-Trapezius -Deltoid -Rhomboid

Smooth muscles are found in

-Walls of blood vessels -Reproductive tract -Respiratory tree -Bladder

T tubules (Transverse tubules)

-continuous with extracellular space, filled with extracellular fluid, conducts and speeds up action potential -come out to meet in sarcolemma (cellular membrane of muscle cells)

Functions of muscles

-contraction, movement -walking, peristalsis, blood pressure

Bundles of fibers (specific to muscle)

-muscle fascicle -surrounded by Perimysium -contains muscle fibers

single cell (specific to muscle)

-myocyte = muscle fibers -surrounded by Endomysium -contains myofibrils

Origin

-fixed end of a muscle -does not move

Sarcomeres

-functional contractile units of skeletal muscle -found inside the muscle cell (myocyte), -contains actin and myosin

Smooth muscle characteristics

-non-striated, involuntary -spindle shaped -Actin and Myosin differently arranged than skeletal muscles -Has ability to regenerate -Involuntary control, not under voluntary control -Gap junctions for coordinated contraction -Regulated by autonomic nervous system

functional unit of contraction

-sarcomere -Z line to Z line -contains thick filaments (myosin)(A bands) -contains thin filaments (actin) (I bands)

3 types of muscle tissue

-skeletal -cardiac -smooth

5 Functions of skeletal muscle

-skeletal movement -maintain posture and body position -support soft tissues -guard/protect entrances and exits of the body -maintain body temperature

Cardiac muscle characteristics

-striated -involuntary -found only in the heart

Characteristics of skeletal muscle

-striated, voluntary, under control of nervous system -Large, long cells formed through fusion of mesodermal cells (myoblasts), contain hundreds of nuclei. Can reach 30 cm -Rich in mitochondria -Terminally differentiated, cannot divide -Satellite cells = stem cells for repair

Organ (specific to muscle)

-the muscle -surrounded by Epimysium -contains muscle fascicles

myosin

-thick filaments -A bands -Dark bands

actin

-thin filaments -I bands -light bands

4 types of synarthrotic joints

1. Suture 2. Gomphosis 3. Synchondrosis 4. Synostosis Suture & Gomphosis are fibrous Synchondrosis are cartilaginous Synostosis are bony

2 types of amphiarthrosis

1. Syndesmosis- bones connected by a ligament 2. Symphysis- bones connected by fibrocartilage

7 major supporting ligaments

1. patellar ligament (anterior) - attaches to tibia 2/3. two popliteal ligaments (posterior) 4/5. anterior and posterior cruciate ligaments (inside joint capsule) 6. tibial collateral ligament (medial) 7. fibular collateral ligament (lateral)

shoulder ligaments

1.coracoacromial 2.coracoclavicular 3.acromioclavicular 3 go across the top and hold humerus coracohumeral glenohumeral

joint

A place in the body where two bones come together

Epimysium, Perimysium, and Endomysium combine to form

A tendon (bundle) or an aponeurosis (a sheet)

Muscle energy source

ATP

Step one of sliding filament theory

Active site exposure Calcium released opens up active site

fat pads

Adipose tissue superficial to the joint capsule Protect articular cartilages

H zone

Area around the M line which has thick filaments (myosin, A bands) but no thin filaments (actin, I bands)

tendons in synovial joints

Attach to muscles around joint Help support joint

Why does skeletal muscle appear striped or striated

Because of the arrangement of alternating dark, thick filaments, myosin (A bands) and light, thin filaments, actin (I bands) within their myofibrils

Number of tendons

Bi or tri

Gomphosis joint

Binds teeth to bony sockets Fibrous connection

Midline (M-line) of the sarcomere

Center of the A band (myosin) dark, thick filaments

Z lines

Center of the I band (Actin) light, thin filaments

Antagonistic pairs of muscles

Contraction of one causes the extension of another

vertebral end plates

Cover superior and inferior surfaces of disc

Synostosis joint

Created when two bones fuse Example metopic suture of frontal bones And epiphyseal lines of mature long bones

Blood vessels do what for muscle cell metabolism?

Deliver oxygen to muscles

joint structure

Determines direction and distance of movement (range of motion or ROM) Joint strength decreases as mobility increases

What molecules are catabolized by mitochondria to create ATP in resting muscles?

Fatty Acids

intervertebral joints

First two cervical vertebrae are joined by a synovial joint Synovial joints lie between adjacent articular processes Adjacent vertebral bodies form symphyses

Step four of sliding filament theory

Free ATP binds to myosin head causing it to release Cross-bridge detachment

hinge joint

Joint between bones (as at the elbow or knee) that permits motion in only one plane

Peak activity of muscles Most ATP produced by glycolysis Mitochondria cannot keep up with ATP demand Mitochondria make only 1/3 of ATP at this point

Lactic acid accumulates in muscles

Muscle soreness caused by

Lactic acid build up muscle tearing from work out contraction

Abduction

Movement away from the midline of the body

opposition

Movement of the thumb to touch the fingertips

Adduction

Movement toward the midline of the body

reposition

Moving to its normal location or other suitable location all or a portion of a body part

Action

Muscle contraction produces movement Flexion, Extension, Abduction, Adduction

skeletal muscles multi-nucleated?

Muscles use a lot of protein so they must make a lot of protein

Muscles work in?

Pairs

Factors that stabilize synovial joints

Prevent injury by limiting range of motion Collagen fibers (joint capsule, ligaments) Articulating surfaces and menisci Other bones, muscles, or fat pads Tendons of articulating bones

functions of skeletal muscles

Produce skeletal movement, Maintain body position, Support soft tissues, Guard openings, Maintain body temperature, Store nutrient reserves-glycogen, muscles, and liver

Sliding filament theory

Resting Sarcomere

synarthrosis joint

Rigid cartilaginous bridge between 2 bones Found between vertebrosternalribs an sternum Also epiphyseal cartilage of growing long bones

bursae of synovial joints

Sacs lined with synovial membrane Contain synovial fluid Reduce friction where ligaments, muscles, skin, tendons, or bones rub together

Stores Ca that binds to tropomyosin-troponin complex to reveal active site on Actin band

Sarcoplasmic reticulum

Epimysium

Separates the muscle from surrounding tissues connected to deep fascia layer of collagen fibers that surrounds the muscle

Theory of muscle contraction

Sliding filament theory

Synarthrosis

Very strong Edges of bones may touch or interlock May be fibrous or cartilaginous

Anterior Longitudinal Ligament (ALL)

a strong fibrous ligament that courses along the anterior surface of the vertebral bodies from the base of the skull to the sacrum

Posterior Longitudinal Ligament (PLL)

a strong fibrous ligament that courses along the posterior surface of the vertebral bodies within the spinal canal from the base of the skull to the sacrum.

sub/luxation

actually means: partial joint dislocation - less than complete dislocation

bone formation recycling

age physical stress hormone levels calcium and phosphorus uptake an excecretion genetic or enviromental factors

bulging disc

aka slipped disc, when the anulus fibrosus is protruding out of the vertebral canal, occurs with age

rheumatism

any disease marked by inflammation and pain in the joints, muscles, or fibrous tissue, especially rheumatoid arthritis.

Cardiac muscle arrangement

arranged in interlocking woven formation

humeroradial joint

articulation between the capitulum of the humerus and head of the radius

glenoidhumeral joint

ball an socket joint between head and humerus and glenoid cavity of scapula greatest ROM of any joint most frequently dislocated joint least stable supported by biceps brachii

Flexion

bending at the joint so that the angle between the bones is decreased

Dorsiflexion

bending of the foot or the toes upward

lateral flexion

bends vertebral column from side to side

Sarcolemma (specific only to muscles)

cell membrane

Ligaments flava

connect laminae of adjacent vertebrae

Diarthrosis axials

coronal-front and back sagittal-left and right transverse- top/bottom

Sarcoplasm (specific only to muscles)

cytoplasm

zone of overlap

densest, darkest area on a light micrograph Where thick filaments (myosin, A bands) and thin filaments (actin, I bands) overlap

Luxation (dislocation)

dislocation or displacement of a bone from its joint

nucleus pulposus of intervertebral disc

elastic gelatinous core absorbs shocks

Cartilages (meniscus)

fibrocartilage pad between opposing bones

joint capsule

fibrocartilage pads at femur-tibia articulations cushion and stabilize joint

glenoid labrum

fibrocartilage ring that deepens glenoid cavity

joint structural classification

fibrous, cartilaginous, synovial,and bony

Plane (gliding) joints

flattened or sightly curved faces limited motion (nonaxial)

Hip Joints

formed by the head of the femur articulating with the acetabulum of the innominate bone triaxial

What does smooth muscle do in digestive and urinary systems?

forms sphincters and produces contractions

Diarthrosis

freely movable joint

synovial joints (diarthroses)

freely movable joints At ends of long bones Surrounded by joint capsule(articular capsule) Contains synovial membrane Synovial fluid from synovial membrane fills joint cavity Articular cartilage covers articulating surfaces Prevents direct contact between bones

coronal plane

front and back jumping jacks anteriorposterior axis

types of movements at synovial joints

gliding-when 2 flat surfaces slide past each other ex: carpal bones angular movements-flexion and extension are movements in the anterior-posterior plane flexion-decreases angle between articulating bones extension-increases angle between articulating bones hyperextension-extension past anatomical position , rotation, special movements

What does smooth muscle do in integumentary system?

goosebumps are caused by arrector pili muscles of hair follicles (smooth muscles)

special movements

inversion/eversion, dorsiflexion/plantar flexion, lateral flexion, protraction/retraction, opposition, depression/elevation

synovial fluid

joint-lubricating fluid secreted by the synovial membrane Egg yolk Contains proteoglycans Primary functions include 1 lubrication 2 nutrient distribution 3 shock absorption Weak joints Stabilized by accessory structures made by fibroblasts

Planes of movement

monoaxial- elbow biaxia- wrist triaxial- shoulder

rotational motion

motion of a body that spins about an axis medial rotation-internal rotation lateral rotation-external rotation away from body

Pronation

movement that turns the palm down

Supination

movement that turns the palm up

inversion/eversion

movements of the sole of the foot medially or laterally

Retraction

moving a body part backward and parallel to the ground

Protraction

moving a body part forward and parallel to the ground

Circumduction

moving the arm in a circle around the shoulder without rotation

Depression

moving the elevated part inferiorly

(skeletal muscle) multipe sarcomeres (intracellular) covered by sarcoplasmic reticulum

myofibril (skeletal muscle)

arthritis

painful inflammation and stiffness of the joints.

plantar flexion

pointing toes

What does smooth muscle do in reproductive and glandular systems?

produces movements

Elevation

raising a body part

What does smooth muscle do in blood vessels?

regulates flow and blood pressure

(skeletal muscle) involved in transmitting the action potential to the myofibril

sarcoplasmic reticulum (skeletal muscle)

saddle joint

thumb joint articular faces fit together like a rider in a saddle bi axial

Amphiarthrosis

slightly movable joint

extension

straightening at the joint so that the angle between the bones is increased

functional joint classification

synarthrosis, amphiarthrosis, diarthrosis

lateral flexion

the act of bending to one side

condylar joint (ellipsoidal joint)

the ovoid condyle of one bone fits into the elliptical cavity of another bone permits movement in 2 planes allowing flexion, extension, adduction, abduction, and circumduction.

Insertion

the point of attachment to the structure that moves

transverse

top and bottom twisting vertical axis

Anulus fibrosis of intervertebral discs

tough outer layer of fibrocartilage attaches disc to vertebrae