Muscular System Flashcards Preview

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Flashcards in Muscular System Deck (28):
1

Antagonist Muscles

- Muscles that cause movement in opposite directions
Ex. Flexor, extensors, tendons, ligament

2

Flexor

Muscle that bend a limb

3

Extensors

Muscles that straighten a limb

4

Tendons

Link muscle to bone

5

Ligament

Link bone to bone

6

3 Muscle times

Smooth muscles
Cardiac muscle
Skeletal muscle

7

Smooth Muscle

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

8

Cardiac Muscle

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

9

Skeletal Muscle

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

10

Why do muscles act in opposing pairs?

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

11

Sliding Filament Theory

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

12

Creatine phosphate

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

13

Aerobic Cellular Respiration

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

14

Fermentation

- Anaerobic
- produces lactate, makes muscle O2 deficient

15

Slow-twitch

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

16

Atrophy

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

17

Hypertrophy

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

18

Fast twitch Type II A

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.

19

Fast Twitch Type II B

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.

20

Myoglobin

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.

21

Z-line

length of muscle fibre that contain actin fibres

22

A-band

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

23

I-band

thin actin filaments

24

H zone

middle of A-band where only think filaments are found

25

M-line

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

26

Cross-bridges

spaces where myosin and actin overlap and attach to each other

27

Calcium job in contraction

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

28

Hemoglobin

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