chap 9 muscular system III

Question 1

motor unit

Answer 1

single motor neuron and all of muscle fibers it innervates

Question 2

ATP

Answer 2

energy for muscle contraction comes from ATP

only small amounts are stored so new ATP must be continually synthesized

Question 3

3 sources of new ATP within muscle fiber

Answer 3

creatine phosphate
anaerobic respiration
aerobic respiration

Question 4

creatine phosphate (CP)

Answer 4

ATP can be sythesized when ADP reacts with creatine phosphate to form creatine and ATP
ADP+CP -> creatine + ATP

Question 5

how long is ATP from creatine phosphate able to last

Answer 5

as long as the level of creatine phosphate is available in the cell
short time during intense exercise

Question 6

how many seconds of sustained activity can CP synthesized ATP last?

Answer 6

8-15 seconds of sustained muscle activity

Question 7

anaerobic respiration

Answer 7

if enery demands exceed oxygen supply to the cell, ATP is synthesized by anaerobic respiration and is used to provide energy for a short time during intense excercise

Question 8

anaerobic respiration is… compared to aerobic

Answer 8

more rapid, but less efficient

Question 9

where does anaerobic respiration occur

Answer 9

in the cytoplasm and begins with glycolysis

Question 10

glycolysis

Answer 10

glucose (six carbon sugar) is split into 2 three carbon compounds called pyruvate

Question 11

what happens to pyruvate after created?

Answer 11

goes through lactic acid fermentation to yield a net of 2 ATP molecules per glucose molecule

Question 12

anaerobic respiration formula

Answer 12

C6H12O6 (glucose) –> pyruvate –> 2 lactic acid + 2 ATP + heat

Question 13

what happens to waste products

Answer 13

lactic acid molecules diffuse out of the cell to blood plasma
liver cells convert

Question 14

what do liver cells convert?

Answer 14

lactic acid + O2 –> eventual glucose molecule

Question 15

aerobic respiration

Answer 15

used during resting conditions or during excercises such as long distance running
also begins with glycolysis in the cytoplasm

Question 16

aerobic respiration is… compared to anaerobic respiration

Answer 16

more efficient but slower

Question 17

what happens to the pyruvate during aerobic respiration

Answer 17

pyruvate are sent into the mitochondria where they go through the citric acid cycle (krebs cycle) and electron transport chain

Question 18

how much ATP is created through aerobic respiration?

Answer 18

36-38 ATP molecules per glucose molecule

Question 19

aerobic respiration formula

Answer 19

C6H12O6 (glucose) –> pyruvate +O2 –> CO2 + H20 + 38 ATP + heat

Question 20

dealing with waste formula

Answer 20

CO2+H20 H2CO3 (carbonic acid) H+ + HCO3

Question 21

oxygen debt

Answer 21

the amount of O2 needed (above that required for resting metabolism) to recover after vigorous exercise
myoglobin will attach to oxygen
for conversion of lactic acid to glucose in liver
for resting cells to replenish their ATP and CP synthesis