Intro to Skeletal Muscle

What does 'skeletal muscle' refer to?

Muscle usually attached at one or both ends to bones.

Fill in the blank: The attachment of a muscle to the bone that moves most when it contracts is known as the __________.

insertion

Fill in the blank: The attachment at the bone that is less likely to move during muscle contraction is known as the __________.

origin

What is the origin of the biceps brachii?

The scapula, including the coracoid process and above the glenoid cavity.

Where does the biceps brachii insert?

Radial tuberosity on the radius.

What happens when the biceps brachii contracts?

It moves the radius more than the scapula.

What is the primary function of muscles?

Muscles apply tension by pulling on their attachment points.

What are the two classifications of muscle roles during movement?

Agonist and antagonist.

What is the role of the agonist in muscle movement?

The muscle that performs the desired action.

What is the role of the antagonist in muscle movement?

The muscle that opposes the desired action.

How do synergist muscles assist the agonist?

They support the primary agonist in performing the action.

What is the purpose of fixator muscles?

To stabilize the origin so that only the insertion moves during contraction.

What is a concentric contraction?

When a muscle shortens while exerting more tension than needed to move a load.

What occurs during an eccentric contraction?

The muscle lengthens while exerting tension insufficient to move the load.

What occurs during an isometric contraction?

The muscle generates a force equal to the load without changing shape, resulting in no movement.

Which muscle contraction type would occur while lifting a weight?

Concentric contraction.

What type of contraction happens when lowering a weight gradually?

Eccentric contraction.

Fill in the blank: Muscles only __________; they do not push.

pull

What is an example of an agonist-antagonist pair during forearm flexion?

The biceps brachii as the agonist and the triceps brachii as the antagonist.

What is the insertion of the biceps brachii?

The radial tuberosity on the radius.

Fill in the blank: The antagonist muscle opposes the movement performed by the __________ muscle.

agonist

How many different muscles do students need to know in the lab?

About 40.

Why is understanding muscle attachments crucial?

It helps to comprehend muscle function and movement.

What is the primary role of fixators in muscle contractions?

To ensure stability of the origin.

Fill in the blank: The __________ muscles assist the primary agonist.

synergist

What are the three types of muscle contractions?

Concentric, eccentric, and isometric.

Give an example of a situation involving isometric contraction.

Holding a position with a weight without moving it.

Fill in the blank: During an __________ contraction, the muscle does not change in length while exerting tension.

isometric

What does the term 'agonist' refer to in muscle function?

The muscle that primarily causes a movement.

Which muscle type is primarily responsible for pulling movements?

Skeletal muscle.

Describe the relation between the biceps brachii and the triceps brachii during arm flexion.

Biceps brachii works as the agonist while triceps brachii acts as the antagonist.

What is the primary function of an antagonist muscle?

To oppose the movement of the agonist.

What kind of contraction is exemplified by carrying a heavy bag and sustaining that weight?

Isometric contraction.

Define synergist muscles' role in muscle movement.

Synergists assist the agonist in performing the desired action.

Fill in the blank: Muscles pull on their __________ points to create movement.

attachment

Fill in the blank: The __________ refers to the muscle's attachment to the bone that moves the least.

origin

What does the concept of muscle pairs refer to?

Muscles often working in opposition to each other.

What anatomical feature provides the attachment point for muscles?

Bones.

Fill in the blank: __________ occurs when a muscle lengthens while resisting a force.

Eccentric contraction

What is the relationship between tension and movement in concentric contractions?

Tension exerted is greater than the load, resulting in movement.

Fill in the blank: A muscle __________ applies force and causes movement.

contraction

What is significant about the radial tuberosity?

It is where the biceps brachii inserts.

In muscle terminology, what does 'insertion' mean?

The point where a muscle attaches to the bone that moves most.

Fill in the blank: __________ muscle contractions result in no movement but maintain tension.

Isometric

What assists the primary agonist in a movement?

Synergists.

What is the primary action of the biceps brachii?

Flexing the forearm.

Fill in the blank: Muscles work in pairs, with one being an agonist and the other its __________.

antagonist.

Which muscle groups are involved in forearm flexion?

Anterior (agonist) and posterior (antagonist) muscles.

Fill in the blank: The __________ describes the attachment of a muscle that primarily remains stationary during contraction.

origin