Bio 210 lecutre exam 3

Transmit signals from the central nervous system (CNS) to muscles or glands, enabling movement and other bodily functions

What is the function of motor neurons?

Muscle tendons that cross the joint help to stabilize joints by keeping tension on tendons. the slight tension or resistance in muscles when they are at rest

What are muscle tones?

Troponin I inhibits the binding of myosin

Troponin T binds to tropomyosin

Troponin C binds to calcium (Ca2+)

What is the function of troponin?

It regulates muscle contraction by physically blocking active sites on actin

What is the function of tropomyosin?

Resting membrane potential (-70 mV)

Identify

Third class lever (Effort applied between fulcrum and load)

Identify

inflammatory disease often resulting in joint pain

What is lyme disease?

Hip joint

What is the name of the joint that uses the acetabulum?

Filament arrangement gives skeletal muscle striations (thin and thick) (actin and myosin)

What produces striations in skeletal muscle cells?

Calmodulin

Calcium activates what protein in smooth muscle contraction?

Myoblasts

What type of embryological cell gives rise to muscle fibers?

view image

What are the steps in muscle contraction?

Thick filament

Identify

ACh

What is an example of neurotransmitters?

Z line (disc)

Identify

Synovial membrane

Identify

Internal dome-shaped muscle that physically separates the thoracic and abdominopelvic cavities

What is a diaphragm?

Physiological inability to contract despite continued stimulation

What is muscle fatigue?

elongated bursa wrapped around a tendon

What is a tendon sheath?

It is when the myosin head pivots and pulls thin filament toward M line

What is a power stroke?

Repolarization

Identify

Axon terminal of neurons

Where are synaptic vesicles located?

The stiffening of muscles with weak rigidity that occurs after death

What is rigor mortis?

ATP and Ca2+ (calcium ions)

Contraction and excitation requires what substances?

act as tracks for myosin thick filaments to slide along, shortening the muscle.

What is the function of actin filaments during muscle contraction?

Responsible for the rhythmic contractions of the heart, which pump blood throughout the body

What is the function of cardiac muscles?

Stabilize the knee joint by preventing excessive forward and backward movement of the tibia (shinbone) relative to the femur (thighbone)

What is the function of the cruciate ligament of the knee?

Glenohumeral joint

What joint is stabilized by the glenohumeral ligament?

Junctional folds

What part of the sarcolemma contains acetylcholine receptors?

Sarcoplasmic reticulum

What is the name of the structure in skeletal muscle cells that functions in calcium storage?

the movement of pointing your foot and toes downward, away from your leg

What is plantar flexion?

Enables the interaction between the proteins actin and myosin

What is the role of calcium ions in muscle contraction?

Contract fast using anaerobic metabolism. Have large stores of glycogen, few capillaries & mitochondria, little myoglobin. designed for short, powerful, and quick bursts of movement.

What is the function of fast glycolytic fibers?

Movement away from the midline

What is abduciton movement?

regulate muscle contraction by blocking the binding sites on actin filaments when the muscle is at rest, preventing myosin from interacting with actin and causing contraction.

What is the role of tropomyosin in skeletal muscle contraction?

Elongated spindle shaped cells arranged in sheets

- Cell diameter size = 5-10 um

- Cell length = 30-200 um

• Has no sarcomeres; no striations

• Has gap junctions

• Contains 16X more actin than myosin

- Allows greater stretching and contracting

What are the characteristics of smooth muscles?

A region between two successive Z discs

What is a sarcomere?

Used for mastication (chewing); elevates & protracts the mandible

What is the function of the masseter?

Holds food between teeth; compresses cheek for whistling and sucking

What is the function of the buccinator?

Smooth muscle cells

What is the name of the muscle cell that has greatest ability to regenerate

Lines the appositional surfaces of the articulating bones and avoids direct bone-to-bone contact during compression of joints

What is the function of articular cartilages?

movement toward the midline

What is adduction movement

The innermost layer that surrounds and electrically insulates each muscle fiber

What is the function of the endomysium?

The mechanism for contraction is explained by the sliding filament theory (model). Muscle fibers contract by the interaction between thin and thick filaments within each sarcomere

What is the sliding filament model of contraction?

Flexes hip joint/thigh. Flexes & laterally rotates the thigh. Flexes & medially rotates the leg. Helps us sit cross-legged

What is the function of the sartorius muscle?

Lubricates and nourishes articular cartilage and acts as a shock absorber during compression of the joint

What is the function of the synovial fluid?

A type of joint in the human body that allows for very little or no movement

What are synarthrotic joints?

articulation between bodies of adjacent vertebrae and diarthrotic articulation between articular processes. Slightly movable joints

What are amphiarthrotic articulations?

Hyaluronic acid

What acid is found in the synovial fluid?

movement beyond the anatomical position

What is hyperextension movement?

Plane joint

Gliding motion in your wrist uses what joint?

share the fundamental ability to contract and use the proteins actin and myosin to generate force.

Compare the functions of skeletal and smooth muscles

The axon terminal of a motor neuron

In muscle contraction acetylcholine is stimulated from where?

O2 storage molecule and gives fibers their red color

What is the function of myoglobin?

a type of skeletal muscle where the muscle fibers (fascicles) run parallel to the long axis of the muscle

What are parallel muscles?

Fibrocartilage separates articular surfaces to improve "fit" of bone ends, stabilize joint, and reduce wear and tear

What are menisci?

It is the fine, delicate, extensible membrane surrounding each muscle fiber

What is sarcolemma?

Common, irreversible,degenerative (''wear-and-tear'') arthritis

What is osteoarthritis?

Peg-in-socket joints of the teeth in alveolar sockets of mandible and maxilla

What is gomphosis?

Bursitis

Inflammation of a bursa due to injury or friction

Diplopia

Double vision

Ptosis

Dropping or falling of upper or lower eyelid

Subluxation

Partial dislocation of a joint

Rheumatoid arthritis

A chronic inflammatory disorder

Temporomandibular junction

Diarthrotic, hinge joint between head (condyle) of mandible and temporal bone of skull.

Isometric contraction

no shortening; muscle tension increases but does not exceed load

Isotonic contraction

muscle shortens because muscle tension exceeds load

Gouty arthritis

Uric acid build-up that causes pain in joints

Myofascial pain syndrome (MPS)

A chronic pain disorder that affects the muscles and fascia (the connective tissue surrounding muscles). Bands of muscle fibers tighten and contract after the skin is stimulated; may produce goose bumps,sweating, flushing of the skin; affects 50% of people in 30-60 yr age range.

Treatment - massage,muscle stretching,NSAIDs

Gower's maneuver

a physical examination finding where a person uses their hands to "walk" up their own body to stand from a prone or squatting position

Dysarthria

a motor speech disorder that results from impaired muscle movement in the face, mouth, and respiratory system, affecting speech clarity and intelligibility

Sarcopenia

age-related loss of skeletal muscle mass, strength, and function

Glycolysis

a metabolic pathway that breaks down glucose to produce 2 pyruvic acid molecules. Produces ATP. Anaerobic.

Myasthenia gravis

a chronic neuromuscular disease that causes weakness in the voluntary muscles. Antibodies attack the neuromuscular junctions and bind up ACh receptors so muscles cannot be stimulated.

Fibromyalgia

Syndrome of chronic severe pain in muscles & skeleton

Duchenne Muscular Dystrophy (DMD)

One of the most severe forms of inherited muscular dystrophies. Genetic disorder and causes progressive muscle weakness and degeneration.

Origin of muscle

point of attachment to bone that does not move

Convergent fascicles

A muscle fiber arrangement where fascicles (bundles of muscle fibers) originate over a broad area and converge towards a single tendon or aponeurosis (a sheet-like tendon)

Parallel fascicles

Where fascicles run parallel to the long axis of the muscle. Ex) biceps brachii and sternocleidomastoid

Creatine phosphate

a high-energy molecule stored in muscles that plays a crucial role in rapid energy production for muscle contraction. Plays a role in the direct phosphorylation of ADP.