Cell Respiration, Fermentation and ATP Flashcards
What does ATP stand for?
Adenosine triphosphate
What are the three parts of an ATP molecule?
Adenine (nitrogen base)
Ribose (5 carbon sugar)
3 phosphate groups
How are ATP, ADP, and AMP different?
ATP = 3 phosphates (fully charged) ADP = 2 phosphates (partially charged) AMP = 1 phosphate (uncharged)
When you _________a bond you release energy and when you __________ a bond you store energy
break (release)
form (store)
Your heart requires energy to beat. How does ATP release energy for this to occur?
breaks the bonds between the phosphate groups
What are some examples of work in the cell that require energy?
active transport (ion pumps)
building polymers (ex. proteins or nucleic acids)
movement (cilia / flagella or even tissues like muscle contractions)
growth
How do animal cells make ATP
by reacting the glucose in their food with the oxygen in the air (cellular respiration)
How is energy stored inside a glucose molecule?
in the chemical bonds.
How are chemical bonds broken and reformed?
By moving electrons. ***Electrons move energy!
Which organelle produces ATP through cellular respiration?
mitochondria
What organisms can do cellular respiration?
ALL of them! BOTH plants and animals do cell respiration.
Define endergonic
Bringing energy in / requires energy to do the reaction
Define exergonic
Sending energy out (remember ex = exit) / releases energy when the reaction happens
For a reaction that is endergonic, is ATP used or made?
Used
For a reaction that is exergonic, is ATP used or made?
Made
What is the equation of cell respiration?
C6H12O6 + 6O2 ——- 6H2O + 6CO2 + 36 ATP
What are the reactants (what goes in) of cell respiration
glucose and oxygen
What are the products of cell respiration?
water, carbon dioxide and ATP
Why are photosynthesis and cell respiration considered opposite practices?
- PS makes what CR uses and CR makes what PS uses.
- Cell respiration puts CO2 into the atmosphere and PS takes CO2 out of the atmosphere.
- PS is an endergonic process and requires energy as a reactant. CR is an exergonic process and releases energy as a product.
Aerobic vs. Anaerobic
Uses oxygen (aerobic) vs. doesn’t use oxygen (anaerobic)
Where in the cell does cell respiration take place?
Prokaryotes: in the cytoplasm
Eukaryotes: in the cytoplasm and in the mitochondria
What are the three steps of cell respiration?
**These are the steps that happen IF oxygen is available
Glycolysis (in cytoplasm)
Krebs Cycle (in mitochondria)
Electron Transport Chain (in mitochondria)
What steps are followed if oxygen is NOT available?
Glycolysis to fermentation (either lactic acid or alcoholic)
Where is ATP produced during cellular respiration?
small amount in glycolysis
small amount in Krebs cycle
large amount in electron transport chain
Glyco -
Lysis -
glyco = sugar lysis = break
Glycolysis breaks sugar
Ins and outs of glycolysis
IN: 2 ATPs and glucose
OUT: 4 ATP and pyruvic acid and 2 NADH
**Net gain is 2 ATP (what you get to keep)
NAD+ / NADH
FAD+ / FADH2
are electron carriers.
+ forms are “empty”
H forms are “full” of electrons.
Transport electrons to the electron transport chains
Counting the carbons:
At the start of glycolysis there are _____carbons in one molecule of glucose.
At the end of glycolysis there are _____carbons in two molecules of pyruvic acid
6 and 6.
- *glucose has 6 carbons
- *pyruvic acid has 3 carbons (2 molecules x 3 carbons = 6 total)
INs and OUTs of Kreb’s Cycle
IN: pyruvic acid (gets turned into acetyl coA first)
OUT: 3 CO2, 4 NADH, 1 FADH2, 1 ATP
Where does Kreb’s cycle happen?
In the mitochondrial matrix (space inside the inner membrane of the mitochondria)
What has to happen to pyruvic acid before it can enter the Krebs cycle?
gets turned into acetyl - CoA.
When this happens a CO2 is released AND an NADH is filled up (goes from NAD+ to NADH).
INs and OUTs of the electron transport chain
IN: NADH, FADH2, and Oxygen
OUT: 32 ATPs
What happens in the electron transport chain
electrons are passed down a chain of molecules and release energy.
The energy is used to pump H+ ions into the intermembrane space (it will diffuse back into the matrix).
At the end of the electron transport chain what happens?
electrons are caught by oxygen (oxygen is the final electron acceptor)
the oxygen combines with excess H+ ions and makes H20 (water)
Why doesn’t the electron transport chain work if there is not any oxygen?
there is nothing at the end of the chain to catch the electrons. Respiration stops and eventually cells will die.
Where does lactic acid fermentation happen?
What does it produce?
Happens in muscle cells.
Glucose undergoes glycolysis and then pyruvic acid produces lactic acid
Where does alcoholic fermentation happen?
What does it produce?
Happens in yeast and some microorganisms.
Glucose undergoes glycolysis and then pyruvic acid makes ethyl alcohol and carbon dioxide (CO2)
Why is fermentation not as good as aerobic respiration?
lactic acid and ethyl alcohol are toxic to cells
