Chapter 2- Musculoskeletal System PART 2

Chapter 2- Musculoskeletal System PART 2

Anterior View

The muscles that can be seen from the anterior view are at the front of the body.

Have a look at the image to find some of the major muscles at the front of the body.

NOTE: Some muscles span around both the front and back of the body.

Multiple Choice

The Rectus femoris, vastus lateralis and vastus medialis make up the muscle more commonly known as the

• Hamstrings

• Deltoids

• Quadriceps

• Abdominals

Multiple Choice

Our chest muscle is known as

• Pectoralis major

• Sartorius

• Biceps

• Deltoid

Multiple Choice

The muscle that attaches to the outside of the bone of the lower leg is known as

• Quadriceps

• External Oblique

• Gastrocnemius

• Tibialis Anterior

Posterior View

The muscles that can be seen from the posterior are at the back of the body.

NOTE: Just like the anterior view, there are some muscles that span around the body and can be seen from the front also.

Multiple Choice

The diamond shaped muscle attaching to the base of the skull, shoulders and upper half of the vertebral column is known as

• Deltoids

• Trapezius

• Latissimus dorsi

• Hamstrings

Multiple Choice

The muscle that spans over the hips and is sometimes called a person's 'powerhouse' is correctly known as

• Latissimus Dorsi

• Abdominals

• Gluteus Maximus

• Hamstrings

Types of Muscles

There are three types of muscles in your body:

Skeletal- attached to bones and responsible for voluntary movement.

Smooth- involuntary muscles found in blood vessels and walls of the intestines.

Cardiac- involuntary muscles that make up the walls of the heart.

Muscle Attachments

* Muscles are attached to bone by tendons.

* The main body of the muscle is called the muscle belly.

* The points of attachment are called the:

- Origin- attachment of the muscle to a stable bone, which the muscle can pull against

- Insertion- attachment of the muscle to a bone that is moved by the action of the muscle.

Multiple Choice

Which of the following bones would be the origin of the biceps?

• Scapula

• Humerus

• Radius

• Ulna

Multiple Choice

Which of the following bones would be the insertion point for the biceps?

• Scapula

• Humerus

• Radius

• Ulna

Muscles working together

Reciprocal inhibition is a term used to explain the relaxation of one muscle to allow for the contraction of an opposing muscle to allow movement.

Agonists are the muscles primarily responsible for movement.

Antagonists are the muscles opposite to the agonist which relax during contraction to allow movement.

Muscles working together

Stabilisers are also involved in contractions by holding or stabilising a body part, making it immobile with another part is moving.

Example: quadriceps may stabilise the knee in an extended position to permit plantar flexion of the ankle when pushing off the ground during the running action.

Multiple Choice

In a squat, the agonist would be the ____________________ and the antagonist would be the _______________.

• Hamstrings, quadriceps

• Gluteus maximus, quadriceps

• Quadriceps, hamstrings

• Hamstrings, gluteus maximus

Multiple Choice

In a bicep curl, the agonist would be the __________________, and the antagonist would be the __________________ and the stabiliser would be the __________________

• Biceps, triceps, deltoid

• Triceps, deltoid, biceps

• Biceps, triceps, quadriceps

• Biceps, deltoid, wrist flexors.

Multiple Choice

In a bench press, the agonist would be the __________________, the major antagonist would be the ________________ and the stabilisers would be the _________________.

• Pectoralis major, trapezius, deltoid

• Pectoralis major, triceps, biceps

• Pectoralis major, biceps, latissimus dorsi

• Pectoralis major, latissimus dorsi, rotator cuff.

Muscle Fibre Arrangement

1. Circular- fibres arranged in rings.

2. Convergent- broad origin converging to single tendon insertion.

3. Parallel- fascicles run parallel to the long axis of the muscle

4. Pennate- fibres are short & attach obliquely to a central tendon

5. Fusiform- muscle belly is wider that insertion and origin.

Multiple Choice

The bicep is an example of a

• Pennate muscle

• Fusiform muscle

• Convergent muscle

• Circular muscle

Multiple Choice

The Sphincter is an example of a

• Convergent muscle

• Parallel muscle

• Circular muscle

• Pennate muscle

Multiple Choice

The pectoralis major is an example of a

• Convergent muscle

• Parallel muscle

• Fusiform muscle

• Pennate muscle

Muscle Arrangement

Pennate muscles come in three forms:

1. Unipennate- Fascicles insert into only one side of the tendon.

2. Bipennate- fascicles insert into opposite into tendon from opposite sides (feather)

3. Multipennate- Looks like many feathers side by side inserted into one large tendon.

Multiple Choice

The fibre arrangement of the deltiod is

• Unipennate

• Multipennate

• Parallel

• Bipennate