Ch. 9 And 10 Test

Front 1

3 methods of ATP production

Back 1

Direct phosphorylation

Aerobic respiration

Anerobic respiration

Front 2

Direct phosphorylation ATP production

Back 2

The fastest form of ATP production

ADP binds with a Creatine phosphate (CP) to make ATP. Only lasts 4-5 seconds

Front 3

Aerobic respiration ATP production

(During rest)

Back 3

Most prefered method by cells, TP lasts hours, occurs in 3 steps: Glycolysis, Citric acid cycle and Electron transport chain

Front 4

3 steps of Aerobic respiration

Back 4

Glycolysis: Glucose is broke down into 2 pyruvic acids and 2 ATP

Citric acid cycle: (Kreb's cycle) Pyruvic acid is broke down into CO2 and 2 more ATP

Electron transport chain and chemiosmosis: Occurs in the crisae of mitochondria, uses o2. Breaks down each glucose molecule into 32-36 ATP

Front 5

Anaerobic respiration ATP production

(Strenuous exercise)

Back 5

Occurs when no oxygen is available. Only produces enough ATP to last 4-5 minutes. Occurs in 2 phases: glycolosis and fermentation

Glycolosis(break down of glycogen into 2 ATP and 2 pyruvic acid)

Fermentation (Pyruvic acid ferment into lactic acid)

Front 6

Muscle tone

Back 6

Is lost if motor nerve axons are cut or disease interferes with impulse conduction

Front 7

How muscles contract happens in 3 steps

Back 7

1. The neuromuscular junction

2. Excitation contraction coupling

3. Cross bridge cycle

Front 8

Muscle contraction step 1.

Neuromuscular junction

Back 8

1.Action potential arrives at axon terminal

2. opens voltage gaited calcium channels, calcium diffuses into axon terminal

3. ACH leaves axon terminal and synaptic cleft

4. ACH bonds onto receptors of motor end plate of sarcolema

5. Sodium channels opens, depolarization begins

6. Action potential fires in sarcolema

7. ACH is released and destroyed by ACH esterase, in the synaptic cleft

Front 9

Muscle contraction step 2.

Excitation, contraction and coupling

Back 9

1. Action potential travels down T tubules into muscle fiber

2. Sarcoplasmic reticulum releases burst of calcium into sarcoplasm (FINAL TRIGGER)

3. Cross bridge cycle begins

Front 10

Muscle contraction step 3.

Cross bridge cycle

Back 10

1. Calcium is released from the sarcoplasmic reticulum, and binds to troponin creating a clamp.

2. Troponin changes shape and releases tropomyosin. Allowing myosin to bind to actin (CROSS BRIDGE) Actin moves to center of the sarcomere

3. ATP breaks down and releases energy. The energy cocks the myosin head and it binds to actin

4. Myosin head pivots and actin is pulled to center of sarcomere (POWER STROKE), creating a contraction

Front 11

Muscle fiber contraction summary

Back 11

1. Action potential is conducted down motor neuron axon

2. Motor neuron terminal releases ACH

3. ACH binds to receptors on the muscle fiber

4. Sarcolema is stimulated, action potential is generated, impulse is conducted to entire muscle through T tubules

5. Impulse reaches sarcoplasmic reticulum, calcium channels open.

6. Calcium ions diffuse from the SR into sarcoplasm bind to troponin molecules

7. Tropomysin moves and exoses sites on actin

8. Actin and myosin link making cross bridges

9. Thin actin filaments are pulled toward the center of the sarcomere by myosin cross bridges

10. The muscle contracts

Front 12

Muscle relaxation

Back 12

1. ACH esterase decomposes ACH muscle fiber is no longer stimulated

2. Calcium ions are activly transported into the SR

3. ATP breaks cross bridge of actin and myosin

4. Breakdown of ATP cocks head of myosin

5. Troponin and tropomyosin molecules inhibit the interaction between myosin and actin filamints

6. Muscle fiber remains relaxed, ready to be stimulated

Front 13

Which parts of a sarcomere contains actin only

Back 13

I band

Front 14

Which part of a sarcomere contains myosin (thick filaments)

Back 14

A band

Front 15

Essay: What triggers the release of ACH out of the axon terminal and into the synaptic cleft?

Back 15

Steps 1-3 of the neuromuscular junction-

1. Action potential arrives at axon terminal

2. Opens voltage gated calcium channels calcium diffuses into axon terminal

3. Exocytosis of ACH out of axon terminal and synaptic cleft

Front 16

Essay: Whatis the specific function of calcium in skeletal muscle contraction?

Back 16

When released from the SR it enters the sarcoplasm and binds to troponin allowing for cross bridge formation, then power stroke, cross bridge detachment and finally reactivation of the myosin head

Front 17

Essay: What causes the release of the myosin head from actin?

Back 17

After the power stroke the leftover ADP is released and a new ATP takes its place, binds to the myosin head which causes myosin and actin to detach.

Front 18

Essay: What resets the myosin head

Back 18

Myosin head is reset from the splitting of ATP in the cross bridge formation phase

Front 19

Essay: What causes muscle relaxation when a motor neuron stops firing?

Back 19

1. ACH esterase decomposes ACH muscle fiber is no longer stimulated
2. Calcium ions are activly transported into the SR
3. ATP breaks cross bridge of actin and myosin
4. Breakdown of ATP cocks head of myosin
5. Troponin and tropomyosin molecules inhibit the interaction between myosin and actin filamints

Front 20

What causes muscle fatigue after excercise?

Back 20

Decline of ph in the muscle fibers, decreasing calcium ion binding to troponin and altering enzyme activities