Prac 2 slides

Question 1

4 classifications of skeletal muscle

Answer 1

1. Parallel
2. Pennate
3. Convergent
4. Circular

Question 2

Parallel Muscle
long and thin, and have a large range of motion

• Describe the fascicle arrangement:
  – What are the two types of parallel muscles?

Answer 2

Fascicles run Parallel to each other

Parallel muscles can be divided into fusiform and non-fusiform types based on their shape.

Fusiform muscles are more spindle-shaped (their diameter at the centre is greater than at either end), whereas, non-fusiform muscles are more rectangular with a constant diameter.

Eg biceps brachii = Fusiform Parallel muscle
sartorius muscle of the thigh = Non fusiform Parallel Muscle

Question 3

Pennate
- more but shorter muscle fibres than parallel, produce strong contraction

Describe the fascicle arrangement:
– What are the three subdivisions of pennate muscles?

Answer 3

Pennate fascicles are short and attach obliquely to a long tendon that extends across the entire muscle.

1. Unipennate
2. Bipennate
3. Multipennate

Question 4

Unipennate

Answer 4

In a unipennate pattern, the muscle resembles one half of a feather (the tendon is represented by the shaft of the feather).

The extensor digitorum of the forearm

Question 5

Bipennate

Answer 5

A bipennate pattern resembles a complete feather, with fascicles attached to both sides of a central tendon
ie rectus femoris

Question 6

Multipennate

Answer 6

Multipennate muscles have fascicles that insert on multiple tendons tapering towards a common tendon, like multiple feathers converging on a central point

ie deltoideus

Question 7

Convergent
- versatile as contractions of different parts may change pull direction

– Describe the fascicle arrangement:

Answer 7

When a muscle has a widespread expansion over a sizable area, but then the fascicles come to a single, common attachment point

eg Pectoralis Major

Question 8

Circular
- Contraction decreases lumen diameter

– Describe the fascicle arrangement:

Answer 8

A circular pattern of fascicles

Found in the mouth or opening of the anus

Question 9

Temporalis

Answer 9

Superior to the temple. Fan-shaped muscle ( Convergent )

Question 10

Frontalis

Answer 10

overlaying the frontal bone

Question 11

Orbicularis Oris and Orbicularis Oculi

Answer 11

Oris surrounds the mouth and oculi surrounds the
eyes
Type: circular

Question 12

Sternocleidomastoid

Answer 12

originates on the mastoid process of occipital bone and attaches to
the manubrium of the sternum and the clavicle

Type : Parallel

Question 13

Platysma

Answer 13

a broad sheet of muscle fibres originating from the clavicle to the angle of the mandible.

Type : Parallel Non fusiform

Question 14

Platysma

Answer 14

a broad sheet of muscle fibres originating from the clavicle to the angle of the mandible.

Question 15

Deltoid

Answer 15

Prime shoulder abductor

Convergent

Question 16

Pectoralis major

Answer 16

Convergent

Question 17

Biceps Brachii

Answer 17

most anterior; flexes shoulder and elbow (synergist) and supinates
forearm

Fusiform Parallel

Question 18

Brachialis

Answer 18

• flexes elbow (prime mover)
  Fusiform Parallel

Question 19

Flexor Carpi Ulnaris (FCU)
most medial muscle of the forearm; flexes & adducts wrist

Answer 19

Fusiform Parallel

Question 20

Palmaris Longus (PL)
– lateral to FCU; not present in all individuals