Muscle Tissue Overview

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Questions and Answers

Epimysia blend into coarse sheets of connective tissue called ______ that bind muscles into functional groups.

fascia

Give the function of synergists.

Synergists assist the agonist muscle in performing an action.

Name two criteria (ways) used to classify / name muscles.

The two criteria used to classify muscles are their action and their location.

Name two descriptive terms used when classifying muscles by their number of origins.

The two descriptive terms used when classifying muscles by their number of origins are biceps and triceps. Signup and view all the answers

Name two descriptive terms used when classifying muscles by their relative size.

The two descriptive terms used when classifying muscles by their relative size are the terms 'major' and 'minor'. Signup and view all the answers

Name two descriptive terms used when classifying muscles by the direction of their muscle fibers.

The two descriptive terms used when classifying muscles by the direction of their muscle fibers are 'rectus' meaning 'straight' and 'oblique' meaning 'angled'. Signup and view all the answers

Each motor neuron axon breaks up into many branches called ______.

axon terminals Signup and view all the answers

The junction between an axon and a muscle cell is called ______.

the neuromuscular junction Signup and view all the answers

The bulk of the body's muscle is composed of which muscle type?

Skeletal muscle. Signup and view all the answers

The fluid-filled gap separating neuronal and muscle fiber membranes is called ______.

the synaptic cleft Signup and view all the answers

Epimysia blend into strong cord-like structures called ______.

tendons Signup and view all the answers

Epimysia blend into strong flat / sheet-like structures called ______.

aponeuroses Signup and view all the answers

Give the two other names by which skeletal muscles are known (Hint: control/appearance)

Skeletal muscles are also known as voluntary muscles because they are under conscious control and striated muscles because of their striped appearance under a microscope. Signup and view all the answers

Skeletal muscle is composed of relatively large, long cylindrical cells, sometimes called ______.

muscle fibers Signup and view all the answers

Give the range of muscle fiber diameter.

Muscle fiber diameter can range from 10 to 100 micrometers. Signup and view all the answers

Give the range of muscle fiber length.

Muscle fiber length can range from a few millimeters to several centimeters. Signup and view all the answers

Muscle cells are bundles of ______.

myofibrils Signup and view all the answers

Myofibrils are made up of even smaller thread-like structures called ______.

myofilaments Signup and view all the answers

What channel is continuous with the sarcolemma and propogates the action potential close to the sarcoplasmic reticulum?

The transverse tubule, or T-tubule, is a structure associated with the sarcolemma, the plasma membrane of a muscle cell. It is a cylindrical invagination that extends from the surface of the muscle cell toward the sarcoplasmic reticulum, enabling the propagation of the action potential deep into the muscle fiber. Signup and view all the answers

A large number of fascicles are bound together by a coarse "overcoat" of dense connective tissue called the ______, which sheaths the entire muscle.

epimysium Signup and view all the answers

Give the function of agonists.

Agonists are the primary movers; they produce the desired action. Signup and view all the answers

Give the function of an antagonist.

Antagonists oppose the action of the agonist. Signup and view all the answers

Give the function of fixators.

Fixators stabilize the origin of the agonist. Signup and view all the answers

What is the effect of aging on muscles what happens to them?

Muscles, like many other tissues, decline in size and strength with aging. This is referred to as 'sarcopenia'. As muscles atrophy, they are less able to generate force, leading to decreased mobility, balance, and overall function. Signup and view all the answers

The transverse tubule and the two terminal cisternae on either side form a region called a ______.

triad Signup and view all the answers

A muscle's fixed (immovable) site of attachment is called its ______.

origin Signup and view all the answers

Several sheathed muscle fibers are wrapped together by a collagenic membrane called?

The collagenic membrane wrapping several sheathed muscle fibers is called the endomysium. Signup and view all the answers

______ are the actual contractile units of a muscle.

Sarcomeres Signup and view all the answers

The ______ is the areolar connective tissue layer surrounding each individual muscle fiber

endomysium Signup and view all the answers

A bundle of several sheathed muscle fibers, wrapped together by a collagenic membrane, are called a ______.

fascicle Signup and view all the answers

A muscle's more movable site of attachment is called its ______.

insertion Signup and view all the answers

A neuron and all the muscle cells it stimulates make up the functional structure called a ______.

motor unit Signup and view all the answers

What is the anatomical name for the thin filaments of the myofibrils?

The anatomical name for the thin filaments of the myofibrils is actin. Signup and view all the answers

What is the anatomical name for the thick filaments of the myofibrils?

The anatomical name for the thick filaments of the myofibrils is myosin. Signup and view all the answers

What part of the sarcoplasmic reticulum is in close proximity with the transverse tubule?

The part of the sarcoplasmic reticulum in close proximity to the T-tubule is called the terminal cisternae. Signup and view all the answers

For what is the sarcoplasmic reticulum a repository?

The sarcoplasmic reticulum is a repository for calcium ions, specifically Ca2+. Signup and view all the answers

How many thin filaments surround every thick filament in each myofibril?

Six thin filaments, composed of the protein actin, surround every thick filament, mainly composed of the protein myosin, within each myofibril. Signup and view all the answers

How many thick filaments surround every thin filament in each myofibril?

Three thick filaments, composed of the protein myosin, surround every thin filament, mainly composed of the protein actin, within each myofibril. Signup and view all the answers

Most abdominal muscles insert at the or the (give either)

pubic symphysis, linea alba Signup and view all the answers

Most abdominal muscles produce an action that or the trunk (give either)

flexes, rotates Signup and view all the answers

Most deep thorax muscles have origins on the ______.

vertebrae Signup and view all the answers

Most abdominal muscles produce an action that moves the or aids in of air into or out the lungs.

trunk, movement Signup and view all the answers

Most posterior muscles of the trunk produce actions that move the or (give either)

shoulder girdle, arm Signup and view all the answers

Most deep facial muscles produce an action that moves some part of the ______.

mouth Signup and view all the answers

Most superficial facial muscles insert in some part of the ______.

skin Signup and view all the answers

Most deep facial muscles insert in some part of the ______.

bones Signup and view all the answers

Most anterior muscles of the neck have insertions in a part of the ______.

hyoid bone Signup and view all the answers

Most anterior muscles of the neck have actions that involve movement of the ______.

head Signup and view all the answers

Most posterior muscles of the trunk have insertions on some part of the or (give either)

scapula, clavicle Signup and view all the answers

Most of the muscles of the humerus / upper arm have insertions in some part the or the .

ulna, radius Signup and view all the answers

Most of the muscles of the upper arm have origins in some part the ______.

humerus Signup and view all the answers

The action of most superficial anterior compartment antebrachium / forearm muscles is ______.

flexion of the wrist Signup and view all the answers

What is the action of most muscles of the anterior upper arm compartment?

Most muscles in the anterior compartment of the upper arm are responsible for flexing the elbow joint, bringing the forearm closer to the upper arm. Signup and view all the answers

What is the action of the muscles of the posterior upper arm compartment?

The muscles of the posterior upper arm compartment are primarily responsible for extending the elbow joint, straightening the arm. Signup and view all the answers

The action of most deep anterior compartment antebrachium / forearm muscles is or (give either)

flexion of the fingers, pronation of the forearm Signup and view all the answers

The action of most deep posterior compartment antebrachium / forearm muscles is ______.

extension of the wrist Signup and view all the answers

The action of most superficial posterior compartment antebrachium / forearm muscles is or (give any one)

extension of the fingers, supination of the forearm Signup and view all the answers

Most of the muscles of the superficial anterior compartment antebrachium / forearm have an origins in some part of the or (give either)

humerus, medial epicondyle Signup and view all the answers

Most of the muscles of the deep anterior compartment antebrachium / forearm have an origins in some part the or (give either)

humerus, ulna Signup and view all the answers

Most of the muscles of the deep posterior compartment antebrachium / forearm have origins in some part the or (give any one)

humerus, lateral epicondyle Signup and view all the answers

The action of all of the muscles of the posterior compartment of the lower leg is ______.

plantar flexion Signup and view all the answers

The actions of all of the muscles of the lateral compartment of the lower leg is or (give either)

eversion, dorsiflexion Signup and view all the answers

All of the muscles of the lateral compartment of the lower leg have origins in some part of the ______.

fibula Signup and view all the answers

Most of the muscles of the superficial posterior compartment antebrachium / forearm have an origin in some part of the ______.

humerus Signup and view all the answers

The action of most of the muscles of the upper medial leg compartment is or (give any one)

flexion of the knee, inversion of the foot Signup and view all the answers

The action of most of the muscles of the anterior upper leg compartment is ______.

extension of the knee Signup and view all the answers

Most muscles of the anterior upper leg compartment have insertions at the or (give either)

tibia, patella Signup and view all the answers

The action of all of the gluteal muscles is ______.

extension and external rotation of the hip Signup and view all the answers

All of the gluteal muscles have insertions at some part of the ______.

femur Signup and view all the answers

Most of the anterior compartment muscles of the upper leg have origins on some part of the or the .

ilium, femur Signup and view all the answers

All of the gluteal muscles have origins at some part of the ______.

ilium Signup and view all the answers

The action of all of the posterior compartment muscles of the upper leg is ______.

flexion of the knee Signup and view all the answers

All of the posterior compartment muscles of the upper leg have origins at the ______.

ischial tuberosity Signup and view all the answers

All of the posterior compartment muscles of the lower leg have insertions at some part of the ______.

calcaneus Signup and view all the answers

All of the muscles of the lateral compartment of the lower leg have an insertion at one of the ______.

metatarsals Signup and view all the answers

Most of the muscles of the anterior lower leg compartment have origins at some part of the or (give either)

tibia, fibula Signup and view all the answers

The action of all of the muscles of the anterior compartment of the lower leg is ______.

dorsiflexion Signup and view all the answers

All of the muscles of the anterior lower leg compartment have insertions at some part of a or a (give either)

cuneiform bone, metatarsal Signup and view all the answers

When ______ muscle contracts blood circulates, delivering nutrients to cells and removing cell waste.

skeletal Signup and view all the answers

______ is a recording of the electrical activity of muscles.

Electromyography (EMG) Signup and view all the answers

______ is an EMG where a needle electrode is inserted through the skin into the muscle whose electrical activity is to be measured.

Intramuscular EMG Signup and view all the answers

______ is an EMG where the electrodes are placed on the skin overlying the muscle.

Surface EMG Signup and view all the answers

______ means changing the strength of muscle contraction or the extent of shortening in proportion to the load placed on the muscle by way of motor unit recruitment.

Graded Contraction Signup and view all the answers

______ is a constant state of slight tension that serves to maintain the muscle in a state of readiness.

Muscle Tone Signup and view all the answers

The muscle force generated by muscle activity is expressed in ______ (units).

Newtons Signup and view all the answers

Study Notes

Muscle Tissue

Epimysia: Blend into coarse sheets of connective tissue called functional groups, which bind muscles into functional groups.
Synergists: Muscles that work together to produce a movement.
Criteria for Muscle Classification: Number of origins, relative size, and direction of muscle fibers.
Muscle Fiber Length Range: (Specific range not provided in the text).
Muscle Fiber Bundles: Muscle cells are bundles of (specific name not given in the text).
Myofibrils: Composed of smaller thread-like structures called (specific name not given in the text).
Motor Neuron Axon Branches: Each motor neuron axon branches into many branches called (specific name not given in the text).
Neuromuscular Junction: The junction between an axon and a muscle cell, called (specific name not given in the text).
Muscle Types: Skeletal muscle is the bulk of the body's muscle.
Epimysium Cord-Like Structure: Epitmysia blend into strong cord-like structures called (specific name not given in the text).
Epimysium Sheet-Like Structure: Epitmysia blend into strong flat/sheet-like structures called (specific name not given in the text).
Muscle Names: Skeletal muscles can be named based on their control or appearance (specific names not given in the text).
Muscle Fiber Diameter Range: (Specific range not provided in the text).
Sarcolemma/Sarcoplasmic Reticulum Channel: Specific channel continuous with sarcolemma and propagates action potential close to the sarcoplasmic reticulum. (specific name not given in the text).
Muscle Fascicle Binding: Large number of fascicles bound together by a coarse "overcoat" of dense connective tissue called the (specific name not given).
Epimysium: Sheaths the entire muscle.
Agonists: Muscles that cause a specific movement.
Antagonists: Muscles that oppose a specific movement.
Fixators: Muscles that stabilize joints.
Aging on Muscles: The effect of aging on muscles, and the changes that occur with aging will not be covered in these study notes.
Muscle Attachment Sites: A muscle's fixed (immovable) site of attachment is called its origin. The movable site is called the insertion.
Muscle Fiber Bundles Encasing Membrane: Several sheathed muscle fibers are wrapped together by a collagenic membrane called the (specific name not given).
Contractile Units of Muscles: (Specific name not given).
Areolar Connective Tissue Layer: The areolar connective tissue layer surrounding each individual muscle fiber is called (specific name not given).
Muscle Fiber Bundles Group: (Specific name not given).
Functional Muscle-Neuron Group: A neuron and all the muscle cells it stimulates make up the functional structure called a motor unit. (specific name not given in the text).
Thin Filaments: The thin filaments of the myofibrils are called (specific name not given).
Thick Filaments: The thick filaments of the myofibrils are called (specific name not given).
Sarcoplasmic Reticulum Proximity: (Specific name, proximity location not covered).
Sarcoplasmic Reticulum Repository: Purpose and content not covered in text.

Muscle Function

Muscle Actions:
- Most Abdominal Muscles: Produce an action that moves or aids the trunk/moves or aids air in/out of lungs.
- Most Posterior Muscles (Trunk): Produce actions that move the (specific action not given).
- Most Deep Facial Muscles: Produce an action that moves some part of the (specific area not given).
- Most Superficial Facial Muscles: Insert in some part of the (specific area not given)
- Most Anterior Neck Muscles: Have insertions in a part of the (specific area not given) and have actions involving movement of the (specific area not given).
- Most Posterior Trunk Muscles: Have insertions on some part of the (specific area not given)
- Most Muscles of the Humerus/Upper Arm: Have insertions on some part of the (specific area not given)
- Most Muscles of the Upper Arm: Have origins in some part of the (specific area not given).
- Most Superficial Posterior Compartment (Antebrachium/Forearm): Have origins in some part of the (specific area not given).
- Most Deep Anterior Compartment (Antebrachium/Forearm): Have origins in some part of the (specific area not given).
- Most Deep Posterior Compartment (Antebrachium/Forearm): Have origins in some part of the (specific area not given).
- Most Posterior Compartment (Lower Leg): Have origins at the (specific area not given)
- Lateral Compartment (Lower Leg): Have origins/insertions in some part of the (specific area or location not provided)
- Anterior Compartment (Lower Leg): (Specific origins/insertions location not covered)
- Upper Leg Compartments: (anterior/medial/posterior) (Specific action, origins/insertions locations not covered)
Most anterior upper leg: Have insertions at the (specific location not given).
Gluteus Muscles: Their action is (specific action not given). All the gluteal muscles have insertions at some part of the (specific location not given).
Posterior Muscle Compartment (Upper Leg): Have origins at the (specific location not given).

Muscle Physiology

Muscle Contraction Types: Isometric (force generated constant), Isotonic (muscle length changes), concentric (shortens), eccentric (lengthens).
Muscle Contractions Mechanism: Describes one way of controlling contraction degree.
Muscle Twitch Phases:
- Shortening Phase: The phase in which muscle fibers shorten.
- Relaxation Phase: The phase in which muscle fibers relax and lengthen.
Measurement of Muscle Force: The force generated by the physiological contraction is called (Specific unit not given).
Stimulus-Response Coupling: The stimulus leads to a contractile response or a non-contractile response.
Restoring Resting Membrane Potential: The process of restoring the resting membrane potential is called (Specific name not given).
Neurotransmitters in Synaptic Cleft/Muscle Stimulation: The neurotransmitter that enters the synaptic cleft is described. Neural Stimulation in rapid succession is described
Waste Product (Oxygen Depleted): Waste product is described
Muscle Readines: Constant state of slight tension called (Specific name not given).
Ion inside Sarcoplasmic Reticulum: (Specific ion not given).
Muscle Contraction Energy: The energy used to drive muscle contraction is called (Specific name not given).
Normal Resting/Potential Membrane: The normal resting potential/membrane potential voltage of a muscle cell is (Specific voltage not given).

Biopac Card

EMG (Surface/Needle Electrode): Recording of electrical activity of muscles (specific descriptions of different types of EMGs).
EMG Parameters: Measurements of power and the amount of work done per unit of time (Specific units not covered).
Other Biopac Card Terms: (Specific terms and definitions not covered).

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Description

This quiz covers key concepts related to muscle tissue, including the classification of muscles, their functions, and structures such as epimysia and myofibrils. It also explores the roles of synergists and the neuromuscular junction in muscle activity. Test your understanding of these fundamental topics in muscle biology.