The Muscular System

Question 1

What is muscle?

Answer 1

Soft tissue containing protein filaments of actin and myosin
- produce force and motion

Question 2

What is a tendon?

Answer 2

Attachment tissue between muscle and bone

Question 3

What is a ligament?

Answer 3

Fibrous tissue connecting bones to other bones

Question 4

What is an aponeurosis?

Answer 4

White fibrous (tendon) in flat muscles having a wide area of attachment
e.g. palma aponeurosis

Question 5

What factors are used to classify muscles?

Answer 5

• orientation of muscle fibres
• action
• shape
• position in body
• no. of heads (proximal attachments)

Question 6

What happens to points of attachment of muscle during contraction?

Answer 6

Muscle contracts and shortens, origin remains fixed, and the insertion moves usually

Question 7

What is the muscle origin?

Answer 7

proximal end (usually) that remains fixed during contraction

Question 8

What is the muscle insertion?

Answer 8

distal end (usually) of muscle that is movable

Question 9

What are the different muscle types in the body?

Answer 9

Cardiac (involuntary)
Skeletal (striated voluntary)
Smooth (non-striated voluntary)

Question 10

What are the different muscle morphologies?

Answer 10

• unipennate
• bipennate
• multipennate
• strap
• fusiform
• circular

Question 11

What are unipennate muscles?

Answer 11

Muscles with fibres pointing in one direction
Fibres insert diagonally to the tendon - strength
- extensor digitorium longum (shin)
- sartorius

Question 12

What is a bipennate muscle?

Answer 12

2 rows of muscle facing opposite diagonal direction, converging on a central tendon
- rectus femoris

Question 13

Describe multipennate muscles

Answer 13

Multiple feather like structures, with athe central tendon branching into 2 or more
- deltoid

Question 14

What are strap muscles?

Answer 14

(parallel) fascicles run parallel to one another

- sartorius, sternocleidomastoid

Question 15

What are fusiform muscles?

Answer 15

Muscle belly fibres are wider than origin and insertion

- biceps brachii, psoas major

Question 16

What are circular muscles?

Answer 16

Muscle fibres are circular

• orbicularis oculi
• orbicularis oris (behind lip)

Question 17

What is an agonistic muscle?

Answer 17

Muscle that contracts to cause movement

Question 18

What is an antagonist muscle?

Answer 18

Opposing muscle, relaxing to stretch

Question 19

What is a fixator muscle?

Answer 19

Keeps limb in place - stabilises joint for movement

- rotator cuff muscles

Question 20

What are synergist muscles?

Answer 20

Muscle acts with another to enhance its effect

Question 21

What is the tibialis anterior?

Answer 21

Laterally on tibia bone

It acts to dorsiflex and invert the foot

Question 22

What are the 4 quadricep (femoris) muscles?

Answer 22

• rectus femoris (anterior to vastus intermedius)
• vastus lateralus
• vastus medialus
• vastus intermedius

Question 23

What is the gastrocnemius muscle?

Answer 23

2 headed Calf muscle (posterior leg)

joins from just above the knee to the heel and ankle joints

Question 24

What is the biceps femoris?

Answer 24

Superficial posterior thigh muscle

Question 25

Which muscles form the posterior thigh?

Answer 25

Bicep femoris (lateral) semitendinosus Semimembranous (medially)

Question 26

Describe the biceps brachii

Answer 26

Front of the upper arm between the shoulder and the elbow - short and long head

Question 27

What is the triceps brachii?

Answer 27

Large muscle on the back of the upper limb | - elbow extension (straightening arm)

Question 28

Outline the agonist and antagonist muscle during bicep brachii contraction

Answer 28

Agonist: bicep brachii (flexion) Antagonist: Triceps brachii

Question 29

Which muscles are the agonist and antagonist during femoris contraction

Answer 29

Agonist: bicep femoris (knee flexion) Antagonist: Rectus femoris

Question 30

What are the 3 gluteal muscles?

Answer 30

- gluteus maximus - gluteus medius - gluteus minimus

Question 31

Where is the sciatic nerve located?

Answer 31

Posteriorly | L4 - S3

Question 32

What causes sciatica?

Answer 32

Sciatic nerve is impinged / irritated causes sciatica | - shooting pain in lower back

Question 33

Which is the smallest muscle in the body?

Answer 33

Stapedius in ear (blocks certain sounds)

Question 34

Which is the longest muscle in body?

Answer 34

Sartorius

Question 35

Name the strongest muscle of the body

Answer 35

Masseter (chewing)

Question 36

Describe the insertion and origin of sternocleidomastoid muscle

Answer 36

Strap muscle Origins: Manubrium, clavicle Insertion: Mastoid process

Question 37

What is the external oblique abdominis?

Answer 37

First outer layer of abdominal muscle Origins: Ant. iliac crest, Inguinal ligament Insertion: lower 4 costal cartilages, abdominal aponeurosis

Question 38

What are compartments?

Answer 38

Muscles are grouped into compartments - each compartment has own nerve and blood supply - muscles in compartments work together to produce movement

Question 39

Outline the venous drainage of compartments

Answer 39

Venous return aided by pressure exerted from connective tissue when muscles contract

Question 40

Describe compartment syndrome

Answer 40

- Trauma to a limb/area - Haemorrhaging + inflammation - Strong fascia - Swelling = inc. Pressure in compartment - Compression of structures

Question 41

Name the hamstring muscles

Answer 41

Posterior compartment of the thigh - Biceps femoris (most superficial) - semitendinosus - semimembranosus (medial)

Question 42

Which bony structure do the hamstring muscles originate from?

Answer 42

Ischial tuberosity

Question 43

What is the insertion point of the hamstring muscles?

Answer 43

Fibula and tibia