Cellular Respiration Quiz: Learn And Practice For Free
During which step is H2O formed?
Answer: ETC
During which step is CO2 produced?
Answer: krebs cycle
During which step is O2 (oxygen) used?
Answer: ETC
During which step is glucose broken down?
Answer: glycolysis
Which step produces the most NADH and FADH2?
Answer: krebs cycle
Which is the correct order of the steps of cellular respiration
Answer: glycolysis > krebs cycle > ETC
Which step provides the most ATP?
Answer: electron transport chain
Which type of fermentation do people do?
Answer: Lactic acid fermentation
Which type of respiration is most efficient?
Answer: Aerobic
The energy in ATP is stored
Answer: in the bond between the second and third phosphate
Where does anaerobic respiration occur?
Answer: cytoplasm
Glycolysis results in a net gain of how many ATP?
Answer: 2
Which molecule isn’t an energy carrier?
Answer: oxygen
14. What is cellular respiration?
Answer: the breakdown of glucose to release ATP
Cellular Respiration’s goal is to
Answer: make ATP
Where does the Krebs Cycle take place?
Answer: mitochondria
What is the correct equation for cellular respiration?
Answer: 6O2 + C6H12O6 -> 6CO2 + 6H2O + Energy
What are the reactants in the equation for cellular respiration?
Answer: glucose and oxygen
In which way are photosynthesis and cellular respiration different?
Answer: Photosynthesis used carbon dioxide, while cellular respiration produces carbon dioxide.
How many ATP are produced in aerobic respiration?
Answer: 36
The mitochondria is responsible for …
Answer: aerobic respiration
22. The expression “feel the burn” means that a person exercising is doing
Answer: lactic acid fermentation
What is the molecule called that mitochondria produce when they respire glucose?
Answer: ATP
What type of respiration requires oxygen?
Answer: Aerobic
What are the products of aerobic respiration?
Answer: Carbon dioxide and water
What happens to your breathing rate when you exercise?
Answer: It increases
A plant is releasing a gas. What is the mosl tlikely the gas?
Answer: oxygen
______________ produces the most ATP.
Answer: aerobic respiration
What is one of the reactants of cellular respiration?
Answer: glucose
All living things do which of the following?
Answer: Respiration
If oxygen is not present, this step will happen after glycolysis
Answer: Fermentation
cellular respiration
Answer: the process in which cells make ATP by breaking down organic compounds
photosynthesis
Answer: the process in which autotrophs convert light energy into chemical energy
which types of organisms undergo cellular respiration
Answer: both autotrophs and heterotrophs
what happens when organic compounds are broken down into simpler compounds
Answer: energy is released
what is the energy released by the organic compound mostly used to do
Answer: produce ATP
the products of cellular respiration (3)
Answer: CO2, water, and ATP
two stages of cellular respiration
Answer: glycolysis and aerobic respiration
glycolysis
Answer: a biochemical pathway in which one six-carbon molecule of glucose is oxidized to produce two three-carbon molecules of pyruvic acid
how photosynthesis and cellular respiration depend on each other
Answer: the products of photosynthesis are the reactants of cellular respiration, and the
reactants of photosynthesis are the products of cellular respiration
anaerobic
Answer: does not require the presence of oxygen
aerobic respiration
Answer: pyruvic acid is broken down and NADH is used to make lots of ATP
what pyruvic acid undergoes with no oxygen present
Answer: fermentation
fermentation
Answer: the breakdown of pyruvic acid by enzymes, bacteria, yeasts, or mold in the absence of oxygen
type of reaction in cellular respiration
Answer: redox
redox reaction
Answer: one reactant loses electrons and another gains electrons
cellular respiration equation
Answer: C6H12O6+6O2—> 6CO2+6H2O+ATP
where the reactions of glycolysis take place
Answer: cytosol
step one glycolysis
Answer: two phosphate groups are attached to one molecule of glucose, ATP converted to ADP
step two glycolysis
Answer: 6-carbon molecule split into two 3-carbon molecules of G3P
step three glycolysis
Answer: G3P molecules lose electrons and receive another phosphate group, two molecules of NAD+ converted into NADH
step four glycolysis
Answer: all phosphate groups are removed from the molecule to make two molecules of pyruvic acid, the four released phosphates convert four ADP to four ATP
net yield of ATP in glycolysis
Answer: 2 ATP
total ATP produced in glycolysis
Answer: 4 ATP
how many NADH molecules produced in glycolysis
Answer: 2 NADH
how NAD+ becomes NADH
Answer: electrons released through glycolysis attach to NAD+
where pyruvic acid goes if there’s no oxygen
Answer: fermentation
what fermentation regenerates
Answer: NAD+
what fermentation does not produce
Answer: ATP
how various fermentation pathways differ (2)
Answer: enzymes and products
the two common fermentation pathways products
Answer: lactic acid and ethyl alcohol
lactic acid fermentation
Answer: pyruvic acid is converted into lactic acid
what is used to make lactic acid
Answer: one hydrogen atom from NADH and one free hydrogen proton
what happens to NADH in lactic acid fermentation
Answer: it is oxidized and converted to NAD+
type of reaction that occurs in muscles during strenuous exercise
Answer: lactic acid fermentation
organ where lactic acid is converted back into pyruvic acid
Answer: liver
the liver
Answer: where lactic acid is converted back into pyruvic acid
how many carbons in lactic acid
Answer: 3
alcoholic fermentation
Answer: pyruvic acid is converted into ethyl alcohol
organisms that use alcoholic fermentation
Answer: plant cells and unicellular organisms
process of alcoholic fermentation (2 steps)
Answer: CO2 is removed from pyruvic acid, two hydrogen atoms added
what is regenerated in alcoholic fermentation
Answer: NAD+
one kilocalorie=? calories
Answer: 1000
efficiency of glycolysis=
Answer: energy required to make ATP/energy released by oxidation of glucose
where pyruvic acid goes when oxygen is available
Answer: aerobic respiration
aerobic respiration produces ?x as much ATP as glycolysis
Answer: 20
two stages of aerobic respiration
Answer: the Krebs cycle and the electron transport chain
chemiosmosis
Answer: process by which ATP is made using the energy released as protons move across a memrbrane
as glucose is oxidized NAD+ is…
Answer: converted into NADH
the Krebs cycle, function
Answer: breaks down acetyl CoA
where the Krebs cycle takes place (eukaryotes)
Answer: the mitochondria
where the Krebs cycle takes place (prokaryotic)
Answer: None
mitochondrial matrix
Answer: the space inside the inner and outer membranes of a mitochondrion
what the mitochondrial matrix contains
Answer: enzymes to catalyze the reactions of the Krebs cycle
in the mitochondrial matrix, pyruvic acid reacts with ? to form ?, and releases a ?
Answer: CoA, acetyl CoA, CO2 molecule
products of the Krebs cycle (3)
Answer: CO2, hydrogen atoms, and ATP
final electron acceptor of ETC
Answer: oxygen
efficiency of cellular respiration=
Answer: energy required to make ATP/energy released by oxidation of glucose
What is represented by the hexagon?
Answer: Glucose (6C)
How many carbon atoms (C) are in one molecule of glucose?
Answer: 6
How many carbon atoms (C) are in one molecule of pyruvic acid?
Answer: 3
In the process of glycolysis, what happens to glucose after it crosses the cell membrane into the cytoplasm of the cell?
Answer: It splits into 2 pyruvic acids when it crossed.
Thinking about the number of carbon atoms in glucose and in pyruvic acid, explain why there is one molecule of glucose on the left side of the arrow and two molecules of pyruvic acid on the right side of the arrow.
Answer: There is only 3 carbon in pyruvic acid, so since glucose had 6 carbon, it split into 2 pyruvics making 6 altogether.
How many ATP molecules are produced during glycolysis?
Answer: 2
Hydrogen-carrying molecules are also produced during glycolysis. What is the symbols of these hydrogen-carrying molecules?
Answer: NADPH
Does glycolysis occur inside or outside the mitochondria?
Answer: Outside
According to Model 2, what happens to pyruvic acid during the Kreb’s cycle?
Answer: It turns into 3 molecules of carbon dioxide.
According to Model 2, where does the change identified in the previous question occur?
Answer: Mitochondrial matrix.
Note the number of atoms of carbon in pyruvic acid and explain why three molecules of carbon dioxide are produced.
Answer: Each pyruvic acid molecule contains 3 carbon atoms and each carbon dioxide molecule contains only 1. 3 x 1= 3
Considering the glycolysis produces 2 pyruvic acid molecules per glucose molecule, how many total CO2 molecules will be produced from the complete breakdown of each glucose molecule? Show a mathematical equation to support your answer.
Answer: 6 because each pyruvic acid has 3 carbons and 2 pyruvic molecules are produced. (3 x 2 =6)
What 2 hydrogen carrying molecules are formed during the Kreb’s cycle?
Answer: NADH, FADH2
Glycolysis
Answer: ATP-2 NADH-2 FADH2-0
Kreb’s cycle (1st pyruvic acid)
Answer: ATP-1 NADH-4 FADH2-1
Kreb’s cycle (2nd pyruvic acid)
Answer: ATP-1 NADH-4 FADH2- 1
What cell structure is the site for the electron transport chain?
Answer: Inner Mitochondrial Membrane
What substance do the carrier proteins transport across the inner mitochondrial membrane?
Answer: H+
What high energy molecules are formed by the electron transport chain?
Answer: ATP
What atom accepts the hydrogen ion at the end of the electron transport chain?
Answer: Oxygen
What molecule is formed as a product of that acceptance?
Answer: Water
Formulate an explanation for why the events of the ETC constitute an aerobic process rather than an
anaerobic process (like glycolysis)
Answer: The ETC is an aerobic process because it requires oxygen.
Glycolysis
Answer: # of ATP produced-2 # of H-carriers produced NADH-2 FADH2-0
Kreb’s Cycle
Answer: # of ATP produced-2 # of H-carriers produced NADH-8 FADH2-2
ETC
Answer: # of H-carriers produced NADH-x3 FADH2-x2
Total ATP Produced
Answer: # of ATP Produced-4 #of H-carriers produced NADH-30 FADH2-4
Grand Total ATP Produced (Add all 3 columns above)
Answer: 38
C6H12O6
Answer: Used in- Glycolysis
6O2
Answer: Used in- ETC
6CO2
Answer: Produced in- Kreb’s Cycle
6H2O
Answer: Produced in- ETC
38 ATP
Answer: Produced in- Glycolysis-2 Kreb’s-2 ETC-34
Compare the ATP available to cells when oxygen is present versus when it is absent. How might this help explain why brain and heart functions are so quickly affected when a person cannot breathe?
Answer: Because there would be only a little bit of ATP able to be produced without oxygen, the cells of the brain and heart would die and the functions would stop.
What are the two substances that may be formed in anaerobic respiration?
Answer: Lactic acid/alcohol + CO2
Recall that two molecules of ATP are formed during glycolysis. Neither fermentation process shown above creates any more ATP. Knowing this, what would you Predict about the cellular energy available to organisms that carry out fermentation?
Answer: They don’t need much energy since glycolysis produces only a little ATP & fermentation produced none.
Research the relationship between overexertion of muscles and the formation of lactic acid. How does this relate to “the burn” felt during strenuous activity?
Answer: When muscles require more energy aerobically, they switch to anaerobic respiration, the lactic acid produced builds up & produces a burning sensation in the muscles.
What common foods involve the process of fermentation? Use your text or other resource to make a list of the foods and the specific organic organisms used.
Answer: Cheese- various fungi Bread- Saccharomyces cerevisiae & other yeasts Yogurt- various bacteria