Chapter 8 Muscular System Week 4 A/P

—Muscle contraction does not require energy (ATP)

—Most ATP is produced via _____ metabolism

(contract) Muscle that performs the movement

Synergists and prime movers are collectively known as _______; (as muscles work together, body movement is coordinated)

—surrounds individual muscle fibers

—______ is the specific neurotransmitter released @ NMJ

Surrounds group of fascicles (entire muscle)

________ stores O2; increasing the oxygen storage capacity of the muscle.

Each nerve cell fiber may stimulate ____ of individual muscle cells

Sliding filament mechanism now able to proceed.—ATP (stored energy) __________

Regulatory proteins involve which of the following?

The neuron & all stimulated muscle fibers

Surrounds individual fascicles

Tendons attach bone to bone

Which are types of Muscle Contractions?

Excess postexercise oxygen consumption: (EPOC) is involved with?

Calcium regulates sarcomeric contraction within the muscle cell

Thick, (dark)

_____ is known as the deep fascia

The filaments do not shorten during contraction

—Holds fascicles together

(Answer is true) Review slide 20 (Summary of Events in a Muscle Contraction)

—Band of dense CT that attaches muscle to bone

The motor end plate is the _______ muscle membrane

Structure of a Muscle: the connective tissue that holds fascicles together is made of which layers?

The ________ releases calcium into cytoplasm

Action potential from the ______ travels to the sarcoplasmic reticulum (SR)

Capacity of a muscle fiber to undergo shortening, becoming thicker

______ has two forms: Concentric contractions and Eccentric contractions

The _____ (neuron fiber) carry the impulses to the muscles

Muscles that assist the prime movers to accomplish a movement; Muscles that stabilize the body during movement

Attached to the more moveable part of skeleton

Attached to more fixed part of skeleton

Select which are correct:

—Generates ATP rapidly allowing for muscle contraction—Supply is limited

—Efficient but has limitations: Slow to start generating ATP and Requires a lot of O2

—EPOC: represents the energy required to reestablish the resting state; from _______

Sarcomeres contract via the sliding filament mechanism: Actin heads bind to myosin, forming cross-bridges.

coordinates impulses

—Partial breakdown of glucose without using O2;Lactic acid also produced which converts to energy when O2 is available

Which of the following are Energy Sources?

Muscles work in pairs

Motor unit: Stronger or weaker contractions use more or fewer motor units respectively

Lets ions through from cell to cell

______- is initiated by the ACh/receptor

Calcium binds to troponin causing which protein(s) to shift off of actin & expose the binding sites?→sliding mechanism

covers muscle fibers

—(Relax) Muscle that produces the opposite movement to that of the prime mover; Must relax, when prime movers contract

Which of the following are primary functions of Skeletal Muscle?

Most movements of the body involve which types of contractions?

Which of the following are Effects of Exercise?

Ability to transmit an electric current along the cell membrane

ACh crosses the synaptic cleft (space @ synapse); attaches to a ACh receptor; at the motor end plate

—Between cells; across which the neurotransmitter must travel.

—Chemical released from a neuron to stimulate the muscle fiber

Aerobic Metabolism→that requires ______

—Storage compounds ensure for an adequate supply of energy (ATP)

______ can be used as an interim energy source; generates ATP independently of glucose

—______ is a chemical released from the neuron to stimulate the muscle fiber

____ Involves Breakdown of creatine phosphate and Anaerobic glycolysis

A muscle cell is stimulated an electric impulse (current) is generated; spreads rapidly along the muscle cell membrane

(Answer is true) Review slide 3 and 4 images

adhesions to keep cells together

Nerve impulses = motor impulses; they are carried by motor neurons and cause movement

Oxidation of nutrients (glucose & fatty acids) within the cell

Muscle relaxes when stimulation ends and calcium is pumped ______ the SR

Motor unit: Select the characteristic's of "fine movement"

The ACh receptor is ______ embedded in the muscle membrane

The sarcomere consists of which of the following?

The point at which a nerve fiber contacts a muscle cell; Synapse

Bundle of muscle fibers (cells); Many bundles make up a whole muscle

—Thin, (light)

Proteins embedded in the muscle cell membrane, to which neurotransmitters attach once they cross the cleft

Sarcomeres contract via the ______ filament mechanism

A broad sheet CT that attaches muscles to bones or to other muscles

Which of the following are classes of levers?

—Point of communication between a neuron and another cell;—E.g NMJ

—New ATP is used to detach myosin heads and move them back into position for another “_____ stroke"

A single neuron and all the muscle fibers it stimulates

Muscle fascicle→Muscle fibre→Entire muscle

What is needed for muscle contraction?

During intense exercise O2 delivery to tissue can’t keep up with the demands of the working muscles

     During the "Sliding filament mechanism" what changes in length as contraction proceeds?

Nerve impulses stimulate skeletal muscle fibers contraction. Where are the impulses coming from?

A partially contracted state of the muscle that is normal even when it is not in use; Posture maintenance

Individual muscle cells, or muscle fibers, are bundled into fascicles, which in turn are bundled into muscles

membrane of a muscle cell

Motor unit: Select the characteristic's of "broad movement"

Endomysium→Perimysium→Epimysium

______ is stored as triglycerides; can be oxidized for energy

—No change in tension; Muscle length changes; Movement (E.g. Walking)

Contraction: The sarcomere is the functional unit of contraction in the ______ muscle fiber

Calcium→Stored in the sarcoplasmic reticulum (SR), (the ER of muscle cells), until released into the cytoplasm by ______

—Great increase in tension; Muscle length unchanged; No movement; Ex. Pushing against an immovable object

Musculoskeletal system as a lever system

Using stored energy (adenosine triphosphate), myosin heads pull actin filaments together within the sarcomeres→cell ____

______ is storage form of glucose—can generate energy both anaerobically & aerobically

Can’t supply enough energy for the first few seconds of muscle contraction

—Receiving membrane of the muscle cell

Cardiac muscle involves which of the following?