What is a neurotransmitter?

A chemical released at the distal end of an axon that stimulates or inhibits an adjacent cell.

Aerobic respiration

The mechanism of ATP that requires oxygen

The mechanism of ATP that requires oxygen is called

Aerobic respiration

What is the perimysium?

The heavy CT layer surrounding each fasciculus.

What is the epimysium?

The dense collagenous CT that surrounds the entire muscle.

Which muscles are responsible for fictions like communication, speaking, writing, gesturing, smiling, & frowning?

Skeletal muscles (of the face, neck, & limbs)

Muscle elasticity

The ability of a muscle to RECOIL to its original resting length after being stretched.

The ability of a muscle to RECOIL to its original resting length after being stretched

Muscle elasticity

Functions of the cardiac muscles:

Providing a major force for moving blood through the circulatory system.

Provides a major force for moving blood through the circulatory system

Cardiac muscle

Describe hypertrophy

The enlargement of muscles after birth in children & adults. It results from an INCREASE in the NUMBER of muscle fibers.

How are skeletal muscle fibers produced?

Several myoblasts fuse to form a single myofiber.

What is a myofilament?

Contains EITHER actin or myosin proteins

Explain the breakdown of ATP:

1. Move Calcium ions into sarcoplasmic reticulum
2. Move the myosin heads during contraction
3. Release cross-bridges

Explain the steps of muscle relaxtion

1. Nerve signal ceases
2. AchE breaks down
3. Active transport pumps in the sarcoplasm
3. Calcium release from troponin
4. Tropomysin covers myosin binding sites

Muscle Contraction

1. Action potential reaches
2. Ach (neurotransmitter)Binds
3. Action potential travels
4. Ca+ release
5. Active sites exposed
6. Myosin binds

Cross bridge cycling

1. Cross bridge formation
2. Recovery stroke
3. Power stroke
4. Cross bridge release

Muscle fibers & muscle facicles related?

A MUSCLE FACICULE is composed of groups of MUSCLE FIBERS

Cellular Respiration

The method of ATP production that can produce up to 36 ATP molecules for each glucose molecule.

The method of ATP production that can produce up to 36 ATP molecules for each glucose molecule.

Cellular respiration

4 Major functional properties of muscle?
(What makes a muscle a muscle?)

1. Contractility
2. Excitability
3. Extensibility
4. Elasticity

Types of muscle tissue

1. Skeletal
2. Cardiac
3. Smooth

Major functions of tendons

1. Connect muscles to dermis
2. Connect muscles to bone

Explain muscle extensibility

The ability of the muscle to stretch beyond its resting length.

Explain contractility

The ability of the muscle to shorten forcefully.

What is the GENERAL term for connective tissue sheets within the body?

Fascia

What are the structural functions of cardiac muscles?

Branched cells that are autorhythmic & respond to nervous or hormonal stimulation

What are the functions of smooth muscle?

1. Move food through digestive tract
2. Emptying the bladder
3. Regulating blood vessel diameter(vasoconstriction)
4. Changing pupil size
5. Contracting gland ducts
6. Moving hair (errector pilli)

Functions of cardiac muscle?

1. Pumping blood
2. Contraction of cardiac muscle provides the major force for propelling blood through blood vessels

Functions of skeletal muscle

Body movement, maintain posture, responsible for producing the majority of heat needed for maintaining body temperature, communication, gesturing, frowning, & smiling.

What type of muscle is responsible for respiration or breathing?

SKELETAL MUSCLE of the thorax & diaphragm

What type of muscle is involved in vasoconstriction?

Smooth muscle

What are the actions of MUSCLE cells?

1. Contract and shorten
2. Contraction of heart chambers
3. Movement of blood through vessels

What is the muscular fascia?

1.It is the dense irregular collagenous CT located superficially that separates & compartmentalizes individual muscles or groups of muscles.
2. The general term for connective tissue sheets within the body.

An increase of excitability would result in:

1. Muscle would contract more readily
2. The muscle would depolarize more readily

What is excitability?

The capacity of a muscle to respond to a stimulus and what allows muscle cells to contract.

What are the 7 functions of the muscular system?

1. Body movement
2. Maintenance of posture
3. Respiration
4. Body heat production
5. Communication
6. Constriction of organs & vessels
7. Contraction of the heart

What are gap junctions?

They are protein channels that connect adjacent CARDIAC muscle cells which allow action potentials to pass from cell-to-cell

What are characteristics of SMOOTH MUSCLE?

1. Overlapping filiform-shaped cells with GAP JUNCTIONS
2. Allow for rapid communication & coordinated movement

Define AUTORHYTHMIC

The spontaneous contraction of cardiac & smooth muscle at somewhat regular intervals without being signaled by the nervous system.

Step-by-step Single Action Potential

1. Limited Na+ channels open
2. Threshold reached
3. More Na+ channels open
4. Na+ move into cell
5. K+ channels open
6. K+ leaves the cell
7. Repolarization

Structural functions of SMOOTH MUSCLE

Over-lapping filiform-shaped cells with GAP JUNCTIONS that allow rapid communication and coordinated movement.

An increase of muscle elasticity allows:

1.The amount of active tension needed to be generated by the muscle in order to contract would increase.
2. The total amount of passive tension that the muscle could generate would increase.
3. The muscle would have difficulty contracting.

What inhibits contraction of the sarcomere, covers the active sites on actin, and prevents myosin heads from binding with actin?

Tropomyosin

Structural functions of SKELETAL MUSCLE

Very long cells that do not contract spontaneously.

What type of muscle is responsible for producing the majority of heat needed to maintain body temperature?

Skeletal Muscles

What must happen in order for an ion to move passively through an ion channel?

1. There must be a difference in the electrical or charge distribution between the inside and outside of the cell.
2. There must be some type of gradient.
3. There must be a difference in concentration of that particular ion on one side versus the other.