cellular respiration

Question 1

what is CR?

Answer 1

most important metabolic reaction
it is the process by which organic molecules are brocken down to produce energy in the from of ATP

Question 2

what is the equation word/chemical

Answer 2

-glucose+ oxygen—> carbon dioxide+ water+ ATP
- C6H1206+ 602—-> 6CO2+6H20+ATP

Question 3

where does the energy go?

Answer 3

60% is lost as heat- necessary to control body temp
40% forms ATP

Question 4

What is ATP?

Answer 4

adenosine triphosphate
ATP is created when ADP combines with a phosphate group
ATP molecule consists of adenosine and a chain on 3 phosphate groups

Question 5

why does CR occur? what is the energy needed for?

Answer 5

to produce energy in the form of ATP
ATP needed for cell division, movement of organelles, active transport, movement of whole cells

Question 6

how does CR occur?

Answer 6

takes place in a series of events
first stage is glycolysis, 2 possible pathways depending on oxygen avaliable.
anaerobic or aerobic

Question 7

describe anaerobic respiration

Answer 7

without oxygen
- occurs in cytoplasm
-if there continues to be no 02 the pyruvate produced in glycolysis is then converted into lactic acid by fermentation
-lactic acid is what we feel as pain and fatigue
- fermentation stage does not produce any additional ATP but glycolysis releases enough energy to convert 2 molecules of ADP into ATP

-enzymes required for anaerobic available in the cytosol of cell therefore glycolysis and the conversion of pyruvate to lactic acid occur in the cytosol.

-lactic acid goes to liver as high levels is toxic for body and gets changed into glucose. to do this 02 required- 02 dept occurs
-02 levels in blood lower and need to be repaid by converting lactic acid into glucose, done by breathing heavy for a period of time.

Question 8

describe aerobic

Answer 8

with 02- occurs in mitochondria( on inner fold called cristae)
- cristae- made of many folds(with enzymes) to increase SA so rate of CR can be increased
- pyruvate broken down by enzymes to produce 36 ATP
- the complete break down of glucose to C02 and H20 requires 02
- one glucose molecule = 38 ATP( 2 in cytoplasm - 36 in mitochondria)

Question 9

what occurs in the first stage?

Answer 9

glycolysis
breaksdown glucose
- produces 2 molecules of pyruvic acid and 2 ATP molecules

Question 10

what occurs in the 2nd stage?

Answer 10

pyruvate breakdown
- takes place in mitochondrion- where enzymes are available to allow next series of reactions to occur.