Lec exam 2 Muscle tissue

Question 1

Functions of muscle tissues

Answer 1

Propels food we eat along gastrointestinal tract
Allows you to bend your joints
Changes amount of air that enters the lung
Pumps the blood to body tissues

Question 2

What percentage is the weight of an adult composed of muscle tissues?

Answer 2

40-50%

Question 3

Functions of Skeletal muscle?

Answer 3

Body movement
Maintenance of posture
Protection and support
Storage and movement of materials - Sphincters
Heat production

Question 4

Body movement of skeletal muscles

Answer 4

• caused by contraction of muscles attached to bone

- produces highly coordinated and localized motion

Question 5

How does the skeletal muscles maintenence posture?

Answer 5

stabilizes joints

Question 6

How does the skeletal muscles protect and support?

Answer 6

• muscles are arranged along the abdominal and pelvic cavity

- protect internal organs and maintain position

Question 7

How do muscle tissue store and move materials?

Answer 7

• The use of Sphincters which contract and relax to regulate passage of material
• Allows voluntary expulsion of feces and urine

Question 8

How does skeletal muscles produce heat?

Answer 8

• Heat produced by energy required for muscle contraction
• it continuously generates heat in order to maintain body temperature
• Why we shiver when were cold to generate heat

Question 9

What are the characteristics of skeletal muscle tissue?

Answer 9

• Excitability
• Conductivity
• Contractibility
• Elasticity
• Extensibility

Question 10

What does excitability mean?

Answer 10

• the ability of a cell to produce a stimulus by changing electrical membrane potential
• Stimulated by neurotransmitters released from neurons

Question 11

What does conductivity mean?

Answer 11

• electrical change that travels along a plasma membrane
• due to voltage gated channels
• in response to neurotransmitters binding

Question 12

What does contractibility mean?

Answer 12

• Exhibited when contractile proteins slide past each other

- enables muscles to cause movement

Question 13

What does elasticity mean?

Answer 13

• The ability of a muscle to return to its original length following either shortening or lengthening of the muscle
• due to titins that act like compressed coils

Question 14

What does extensibility mean?

Answer 14

• Lengthening of the muscle cell

- due to partial overlap of thick and thin filament in the sarcomere

Question 15

Fascicles

Answer 15

muscle fibers organized into bundles

Question 16

Epimysium

Answer 16

layer of dense irregular connective tissue that surrounds the whole skeletal muscle

Question 17

Perimysium

Answer 17

surrounds fascicles and is dense irregular connective tissue that contains blood vessels and nerves that supply fibers

Question 18

Endomysium

Answer 18

innermost connective tissue layer, surrounds and electrically insulates each muscle fiber and contains reticular proteins to help bind neighboring muscle fibers

Question 19

What are the three concentric layers of connective tissue?

Answer 19

Epimysium, perimysium and endomysium

Question 20

Tendon

Answer 20

thick cordlike structure composed of CT
Formed by the 3 connective tissue layers
Attaches muscle to bone, skin or another muscle

Question 21

Aponeurosis

Answer 21

thin, flat sheet of dense irregular CT

also formed from the 3 CT layers

Question 22

Deep Fascia

Answer 22

additional sheet of dense irregular CT outside the epimysium that separates individual muscles and binds together muscles with similar functions. Contains nerves, blood vessels and lymph and fills space between muscles

Question 23

Superficial fascia

Answer 23

Separates muscle from skin