Week 6 - Skeletal Muscle Tissue

Question 1

What structures do collagen fibres of muscle fascicles merge into?

Answer 1

Tendons or aponeuroses

Question 2

Where do tendons attach muscles?

Answer 2

To specific points on bone

Question 3

What is the function of an aponeurosis? and give example of where it’s located

Answer 3

Provides attachment over a large area, such as skull and abdomen

Question 4

How do some muscles attach directly to bone?

Answer 4

By their epimysium fusing to periosteum

Question 5

What are muscle fibres in a single fascicle called?

Answer 5

Fascicles

Question 6

How does the organization of fascicles in relation to the muscle tendon vary?

Answer 6

It varies based on the amount of power and range of motion a muscle can produce

Question 7

What are the four major arrangements of muscles based on fascicular organization?

Answer 7

Parallel, pennate, convergent and circular

Question 8

Describe parallel muscles.

Answer 8

Their fascicles run parallel to the long axis, all in the same direction, and they have a large range of motion.

Question 9

What is the characteristic feature of pennate muscles?

Answer 9

Their fibres run at an oblique angle to tendon insertion.

Question 10

Give an example of a unipennate muscle.

Answer 10

Extensor digitorum (forearm)

Question 11

What is the function of multipennate muscles? and give an example

Answer 11

They allow for a high degree of power generation due to the arrangement of their fibres. Deltoid muscle

Question 12

Explain the structure of convergent muscles.

Answer 12

Fascicles extend over a broad area and converge on a common attachment site.

Question 13

What type of muscle is a sphincter?

Answer 13

A circular muscle

Question 14

What is the function of circular muscles?

Answer 14

Serves as a sphincter around an opening

Question 15

How do muscles move bones in the body?

Answer 15

By applying force to pull bones via joints, acting as levers

Question 16

What determines the force, speed, and direction of muscle contraction?

Answer 16

The nature and site of muscle attachment

Question 17

What is the relationship between force and distance in levers?

Answer 17

Force × distance = resistance × distance

Question 18

How do levers change the direction of an applied force?

Answer 18

By altering the position of the fulcrum relative to the load and effort

Question 19

Explain the concept of mechanical advantage in levers.

Answer 19

It allows a small force to move a large load over a short distance.

Question 20

Explain the concept of mechanical disadvantage in levers.

Answer 20

It allows a big force to move a light load over a long distance

Question 21

Give an example of a first-class lever in the body.

Answer 21

The flexion/extension of the neck at the atlanto-occipital joint

Question 22

Describe the characteristics of a second-class lever.

Answer 22

The force is further away from the fulcrum than the load, providing a mechanical advantage.

Question 23

What is the main function of third-class levers?

Answer 23

They allow small loads to be moved long distances at fast speeds, working at a mechanical disadvantage.

Question 24

Why is it easier to lift lighter weights than heavier ones?

Answer 24

Because speed is inversely related to load, and it takes longer for movements to begin with heavier weights.

Question 25

What is the optimal combination of tension and speed for a given load in muscles?

Answer 25

Each muscle has an optimal combination of tension and speed for a given load.

Question 26

What is the function of muscles in relation to joints?

Answer 26

All muscles cross at least one joint and produce movement when contracted.

Question 27

What are the two attachments of muscles?

Answer 27

Origin (proximal) and Insertion (distal)

Question 28

How do muscles work in pairs or groups?

Answer 28

One muscle acts as the prime mover (agonist), while the other acts as the antagonist, relaxing when the agonist contracts.

Question 29

What is the function of synergist muscles?

Answer 29

They assist the prime mover, making its action more efficient.