A&P1 Lecture 3

Twitch

What is the term for single contraction-relaxation cycle in a muscle fiber?

Motor unit

A single motor neuron and all the muscle fiber it innervate (supply with nerves) is called?

Recruitment

Increase in muscle tension produced by increasing the number of active motor units is known as…

thin and thick filaments

In aliding filament theory, what structures become connected by myosin cross bridges during muscle contraction

Breakdown acetylcholine into acetate and choline components

What is the specific role of acetylcholinesterase at the neuromuscular junction?

Cross-bridge detachment

During the muscle contraction cycle, what event is directly caused by atp binding to the myosin head?

Troponin

When calcium ions are released from the Sarcoplasmic reticulum, what protein do they bind to, initiating contraction?

Neuromuscular junctions

What is the name of specialized synapses where communication between axons and muscle fibers occur?

Calcium ions

The arrival of action potentials along the transverse tubules triggers the sarcoplasmic reticulum to release what substance?

Sliding filament theory

The structural theory explaining how a muscle fiber contracts is called…

Triad

What is the term for the complex formed by 1 T-tubules and 2 adjacent terminal cisternae?

Myosin

Thick filaments in myofibril are primary composed of which protein?

Actin

Thin filament in myofibril are primarily composed of which protein?

Tropomysin rolls away from active site on actin

During muscle contraction the binding of calcium to troponin causes what direct conformational change?

To conduct the action potential deep into the muscle fiber

What is the function of transverse tubules (t-tubules) in a skeletal muscle fiber?

Zone of overlap get larger but Sarcomere itself is shortened

When skeletal muscle fiber contracts, what happens to the zones of overlap within the Sarcomere?

A-band

Region of Sarcomere that contains thick filament

I-band

Region of the Sarcomere that contains the thin filament

Tendon

Bundle of collagen fibers at the end of the skeletal muscle that attaches the muscle to bone

endomysium

Delicate connective tissue that surrounds individual skeletal muscle fibers

Group of muscle fiber surrounded by perimysium

What is fascicle in the context of skeletal muscle structure?

Synarthrosis

Immovable joint, like suture in skull, is functionally classified as…

Amphiarthrosis

A slightly moveable joint, like pubic symphysis, is functionally classified…

diarthrosis

A freely moveable joint, includes all synovial joints, is functionally classified…

Gomphosis

What type of synarthrosis binds teeth to the bony sockets in the mandible and maxillae?

Synostosis

Epiphyseal line formed after bone growth has stopped is a structure example of…

Synchondrosis

Articulation of ribs with the sternum is example of what type of cartilaginous joint?

Symphysis

Term for joint formed by Fibrocartilage pad between the two pubic bones…

Lubrication, nutrients distribution, and shock absorption

Primary function of synovial fluid within joint cavity

Bursae

Small, fluid-filed pockets that cushion areas where tendons or ligaments rub against other tissues is called

Hyperextension

Which movement describes an extension of limb past the anatomical position?

Medial rotation

Movement of rotating a limb toward the anterior surface of the body…

Lateral rotation

Movement of rotating a limb outward, away from the body’s midline…

Plantar Flexion

What specific movement of the foot that enables a ballerina to stand on her toes?

Inversion

Twisting motion of the foot that turns the sole inward..

Opposition

Unique movement of the thumb that allows it to touch the tips of the other fingers…

Pivot joint

Type of synovial joint that is the atlantoaxial joint which permits rotation of the head

Flexion and extension

Nodding your head “yea” is example of which two angular movements?

Gliding joints

Joints between the carpal bones of the wrist, which allow for slight sliding movements, are classified…

Dorsiflexion and plantar Flexion

Ankle joints is a hinge joint that persists which two specific movements?

Abduction

Movement away from the midline of the body in the frontal plane..

Adduction

Movement of bringing a limb back towards the body’s midline..

Cruciate ligaments: Anterior cruciate ligament (ACL) and posterior cruciate ligament (PCL)

Which two ligaments of the knee are responsible for limiting the anterior-posterior movement of tibia?

Patellar ligament

Ligaments that provide support to front of the knee joint and connects the patella to the tibial tuberosity…

nucleus pulposus

Gelatinous core of an intervertebral disc, which acts as a shock absorber…

Annulus fibrosus

Tough Fibrocartilage outer layer of an intervertebral disc…

Wave summation

If second stimulus arrows at a muscle before the relaxation phase has ended. A more powerful contraction occurs, called…

Incomplete tetanus

A muscle producing almost peak tension during rapid cycles of contraction and relaxation is in a state of…

Complete tetanus

A muscle that is simulated at such high rate that relaxation is eliminated, it produces a steady maximum tension called…

Muscle tension exceeds the load, muscle shortens or lengthens to lift load

In an isotonic contraction what is the relationship between muscle tension and load?

Tension rises but muscle length remain constant

What occurs during an isometric contraction

Rigor mortis

Post-mortem condition where muscle fibers run out of ATP, causing myosin heads to remains attach d to actin…

Synaptic cleft

Narrow space between synaptic terminal of neuron and the muscle fiber…

Assist with repair of damaged muscle tissue

primary function of satellite cells located between Endomysium and Sarcolemma

Decrease of H band and I band during contraction

What physical evidence supports the sliding filament theory of muscle contraction?

Titin, a elastic protein

Protein that is part of thin filament but does not get connected by myosin crossbridge..

Testosterone

Hormones that directly stimulates the growth of muscle tissue, leading to increase muscle mass..

Cardiac muscle tissue

Which type of muscle responsible for forcing blood from the heart into major arteries?

Sarcolemma

The plasma membrane of a muscle fiber

Store and release calcium ions (Ca2+)

Primary function of Sarcoplasmic reticulum (SR) in muscle cells

Contractility

Common property of muscle tissue that allows it to shorten and generate force..

Epimysium

Connective tissue layer that surrounds an entire muscle

Perimysium

Connective tissue layer that surrounds a bundle of muscle fiber..

I-band

In the Sarcomere, what contains only thin filaments?

H-zone (or H-band)

In the Sarcomere, what is the region in the center of the A-band that contains only thick filaments?

Latent period

Which phase of a muscle twitch occurs between the arrival of a action potential and the beginning of tension development?

Eccentric isotonic contraction

Type of muscle contraction involves the muscle lengthening while reducing tension

Cori cycle

Liver and convert lactate produced during anaerobic activity back into glucose through a process called…

Fast fibers (type II b)

Type of skeletal muscle fibers that are characterized by a large diameter, rapid fatigue, and low myoglobin content…

Hypertrophy

Increase in muscle fiber size due to exercise and training

Smooth muscle

Type of muscle tissue characterized by being non-striated, involuntary, and having single nucleus

Saddle joint

Joint between trapezium and metacarpal bone of the thumb is an example of what type of synovial joint?

Ball and socket joint

Shoulder joint, which permits greatest range of motion, is what type of synovial joint?

Anterior cruciate ligament (ACL)

Which of the decent major ligaments of the knee prevents anterior displacement of the tibia?

Collateral (tibial and fibular) ligaments

Ligament that prevent medial and lateral displacement of the knee are

Acromioclvicular and coracoclavicular ligaments

The two ligaments that connect the clavicle to the scapula, providing critical stability to AC joint…

Osteoarthritis

Degenerative joint disease known as wear and tear arthritis, where cartilage breaks down…

Rheumatoid arthritis

Chronic, systemic autoimmune disorder where the immune system system attacks the synovial membranes of joints…

Pronation

Movement of rotating the forearm so the palm faces posteriorly

Supination

Movement of rotating the forearm so the palm faces anteriorly

Protraction

Movement of moving the jaw anterior in a horizontal plane..

Medial and lateral collateral ligaments

Ligaments that resists valgus stress (force pushing the knee inward)

Ligaments that resist the varus stress (force pushing the knee outward)

Anterior and posterior cruciate ligaments

Ligaments that prevents anterior displacement of tibia

Ligament that prevents posterior displacement of tibia

Supraspinatus, infraspinatus, teres minor, and subscapularis

Rotator cuff muscles of the shoulder joint

Subdeltoid, subcoracoid, subacromial, subscapular

Bursae of shoulder joint