Muscles

Question 1

What are the three major parts of muscles?

Answer 1

1) HEAD (caput): at the origin
2) BELLY (ventrer): active muscle
3) TAIL (cauda): passive; at the insertion

Question 2

What are the two major parts that each muscle has?

Answer 2

1) ORIGIN (origo)
2) INSERTION (insertio)

Question 3

Where is the origin of the muscle usually located?

Answer 3

at the proximal end of the muscle (the one closest to the body axis)

Question 4

What are the different types of muscles?

Answer 4

spindle shaped muscles
wide muscles
two headed muscles
three headed muscles
four headed muscles
two bellied muscles
circular muscles
sphincter muscles

Question 5

What are “synergistic muscles”?

Answer 5

When two muscles work together

Question 6

What are muscles called when they work together?

Answer 6

synergistic muscles

Question 7

What are muscles called when they work against each other

Answer 7

antagonistic muscles

Question 8

What is the fixed point? In Latin?

Answer 8

• punctum fixum
• every point that remains immobile (due to its attachment to the trunk)

Question 9

What is “muscle tonus”?

Answer 9

the minimal amount of tension that every muscle is under.

Question 10

What does anaesthesia invoke? (what type of -tonus?)

Answer 10

hypotonus

Question 11

What are the two types of contractions?

Answer 11

isometric and isotonic

Question 12

What is an isotonic contraction?

Answer 12

at a certain tention, the muscle slowly begins to contract and shorten

Question 13

What is an isometric contraction?

Answer 13

continual increase in muscle tension without a change in muscle length

Question 14

How can muscles be categorized?

Answer 14

• depending on the number of joints they act upon
• depending on the functional effects they have on joints

Question 15

How are muscles categorized depending on the number of joints they act upon

Answer 15

• uniarticular muscle
• biarticular muscle
• polyarticular muscle

Question 16

How are muscles categorized depending on the functional effects they have on joints?

Answer 16

extensor
flexor
adductor
abductor
sphincter
dilator
levator
depressor
rotator

Question 17

What are the accessory structures of muscles?

Answer 17

1) FASCIAE
2) BURSAE
3) TENDON SHEATHS

Question 18

What are fasciae?

Answer 18

• muscles are individually sheathed in fasciae
• expansive, thin, meshlike sheets
• consist of collagen and elastic fibres

Question 19

Which direction are fasciae oriented?

Answer 19

the same direction as the tension and stress forces acting upon the muscle.

Question 20

What is the function of fasciae?

Answer 20

• origin and attachment sites for muscles,
• provide support for surrounding tissues (by forming ringlike structures),
• help reduce friction,
• play a supportive role for the tissues and organs.

Question 21

What two layers can fasciae be divided into?

Answer 21

1) Superficial fascia: thin
2) Deeper layer (superficial
profunda): thicker and stronger

Question 22

What are synovial bursae?

Answer 22

• enclosed in a capsule of connective tissue
• vary in size
• always filled with synovia
• compared to small gel cushions located beneath tendons

Question 23

What is the function of the synovial bursae?

Answer 23

evenly distribute pressure originating from the tendon

Question 24

What are the two layers of synovial bursae?

Answer 24

stratum synoviale (inner)
stratum fibrosum (outer)

Question 25

How are bursae classified?

Answer 25

depending on their location

Question 26

What are the different types of bursae?

Answer 26

1) subtendinous bursae 2) submuscular bursae 3) subligamentenous bursae 4) subcutaneous bursae

Question 27

What are synovial tendon sheaths?

Answer 27

- similar to bursae - completely sheath the tendon like a tube - have cavities filled with synovial fluid - synovial membrane (visceral and parietal layers)

Question 28

What is the function of synovial tendon sheaths?

Answer 28

- protect the underlying tissues from pressure exerted by the tendon, - reduce friction during movement