Muscular System

Question 1

Antagonist Muscles

Answer 1

• Muscles that cause movement in opposite directions

Ex. Flexor, extensors, tendons, ligament

Question 2

Flexor

Answer 2

Muscle that bend a limb

Question 3

Extensors

Answer 3

Muscles that straighten a limb

Question 4

Tendons

Answer 4

Link muscle to bone

Question 5

Ligament

Answer 5

Link bone to bone

Question 6

3 Muscle times

Answer 6

Smooth muscles
Cardiac muscle
Skeletal muscle

Question 7

Smooth Muscle

Answer 7

• non-striated
• One nucleus
• Long and narrow (tapered)
• Found in blood vessels, iris, walls of organs
• Involuntary contraction
• does not fatigue easily

Question 8

Cardiac Muscle

Answer 8

• Only in heart
• Tubular, striated and branched
• One nucleus
• Involuntary contraction

Question 9

Skeletal Muscle

Answer 9

• Tubular and striated
• Many nuclei, many mitochondria
• Long
• voluntary contraction
• often in pairs
• supports body

Question 10

Why do muscles act in opposing pairs?

Answer 10

One muscle must contract to make a joint bend, which is the flexor, and the other must contract to make the joint straighten, which is called the extensor. They push against each other to make the bones move. When one muscle contracts, the other always extends.
- Muscles can only pull

Question 11

Sliding Filament Theory

Answer 11

• Explains how muscle contraction occurs
• Z lines move closer together
• Actin and myosin bind to create cross-bridges and go past each other

Question 12

Creatine phosphate

Answer 12

• Creatine phosphate regenerates ATP, it is used as the first energy source for muscle contraction
• First 8 seconds
• Anaerobic
• creatine phosphate + ADP -> ATP

Question 13

Aerobic Cellular Respiration

Answer 13

• Needs O2
• Provides most of muscles ATP requirements
• ATP produced from glycogen -> glucose, fats -> fatty acids
• myoglobin stores O2 and gives muscle color

Question 14

Fermentation

Answer 14

• Anaerobic

- produces lactate, makes muscle O2 deficient

Question 15

Slow-twitch

Answer 15

• Slowly contracts
• resists fatigue
• best for endurance
• aerobic

Question 16

Atrophy

Answer 16

Atrophy occurs when there is a lack of use which then causes a decrease of size in muscles.

Question 17

Hypertrophy

Answer 17

increase of size in skeletal muscle from physical exercise like weightlifting.

Question 18

Fast twitch Type II A

Answer 18

This fiber relies on both anaerobic and aerobic energy(high O2). They contract faster than a slow-twitch fiber and so they are more resistant to fatigue than fast-twitch type II B.

Question 19

Fast Twitch Type II B

Answer 19

This fiber is not able to last long, as it uses anaerobic energy, so it is more of a power muscle. It gets tired very quickly so this fiber is best for sprinting.

Question 20

Myoglobin

Answer 20

This is an iron and oxygen binding protein that can be found in muscle tissue. It stores oxygen and carries it to the muscle tissue, and also gives the muscle its colour.

Question 21

Z-line

Answer 21

length of muscle fibre that contain actin fibres

Question 22

A-band

Answer 22

full length of myosin filaments including the part that overlaps with actin filaments

Question 23

I-band

Answer 23

thin actin filaments

Question 24

H zone

Answer 24

middle of A-band where only think filaments are found

Question 25

M-line

Answer 25

Center of H zone where thick filaments (myosin) are bound in center

Question 26

Cross-bridges

Answer 26

spaces where myosin and actin overlap and attach to each other

Question 27

Calcium job in contraction

Answer 27

- relseased by sarcoplasm | - bonds w/ troponin, changing its shape

Question 28

Hemoglobin

Answer 28

- red blood cell - transport oxygen (99%) and carbon dioxide - carries O2 from lungs to rest of the body