Biology Chapter 9 Test
Cells use the energy stored in chemical bonds of foods to produce compounds that directly power the cell's activities, such as ______
ATP
________ is the only product of the Krebs cycle that is not re-used or used in other stages of cellular respiration.
carbon dioxide.
In prokaryotes, the electron transport chain is in the ______
cell membrane
_________ takes place in nearly all life
cellular respiration
process that releases energy from food in the presence of oxygen
cellular respiration
What is cellular respiration
cellular respiration is the process that releases energy from food in the presence of oxygen.
A calorie is a unit of_____
energy
If cellular respiration took place in just one step, most of the _____ would be lost in the form of light and ____
energy; heat
process by which cells release energy in the absence of oxygen
fermentation
Where do organisms get energy
food
What other kinds of molecules can be used to produce ATP in cellular respiration
glucose, lipids, proteins, complex carbohydrates that can be broken down into glucose
first set of reactions in cellular respiration during which 1 molecule of glucose, a 6-carbon compound, is transformed into 2 molecules of pyruvic acid, a 3-carbon compound.
glycolysis
the Calorie used on food labels is equal to ______ calories
1000
The equation that summarizes cellular respiration, using chemical formulas is_______
602+C6H12O6 > 6CO2 + 6H2O+ Energy
At the end of glycolysis, about _____ percent of the chemical energy is locked in the bonds of the _______ molecule.
90; pyruvic acid
What happens during the process of glycolysis
During glycolysis 1 molecule of glucose, a 6 carbon compound, is transformed into 2 molecules of pyruvic acid, a 3 carbon compound.
What happens during the Krebs cycle
During the Krebs cycle pyruvic acid is broken down into carbon dioxide in a series of energy-extracting reactions.
How does the body produce ATP during different stages of exercise?
For short, quick bursts of energy, the body uses ATP already in muscles as well as ATP made by lactic acid fermentation. For exercise longer than about 90 seconds, cellular respiration is the only way to continue generating a supply of ATP.
What are two advantages of glycolysis?
Glycolysis occurs very quickly, which allows it to supply ATP if energy demand suddenly increases. Glycolysis can quickly supply energy to cells when oxygen is not available.
How do organisms generate energy when oxygen is not abailable
In the absence of oxygen, fermentatino releases energy from food molecules by producing ATP.
second stage of cellular respiration in which pyruvic acid is broken down into carbon dioxide in a series of energy-extracting reactions
Krebs cycle
electron carrier involved in glycolysis
NAD+ (nicotinamid adenin dinucleotide)
What is the relationship between photosynthesis and cellular respiration?
Photosynthesis removes carbon dioxide from the atmosphere, and ellular respiration puts it back. Photosynthesis releases oxygen into the atmosphere and cellular respiration uses that oxygen to release energy from food.
How does the electron transport chain use high-energy electrons from glycolysis and the Krebs cycle
The electron transport chain uses the high-energy electrons from glycolysis and the Krebs cycle to convert ADP into ATP.
Why is it an investment for the cell to use two ATP at the beginning of glycolysis?
The end result of glycolysis is the production of four ATP. Using two ATP at the start of glycolysis gives the cell a net gain of two ATP.
How much ATP does cellular respiration generate
Together, glycolysis, the Krebs cycle, and the electron transport chain release about 36 molecules of ATP per molecule of glucose.
How many ATP molecules per glucose molecule does a cell gain from each of the three stages of cellular respiration.
a cell gains 2 atp molecules per glucose molecule from glycolysis, 2 more ATP molecules from the Krebs cycle and 32 ATP molecules from the electron transport chain.
The compound that joins with a 4-carbon molecule in the Krebs cyycle is called _____
acetyl-CoA
process that requires oxygen
aerobic
The pathways of cellular respiration that require oxygen are said to be _____. Pathways that do not require oxygen are said to be _____.
aerobic; anaerobic
Process that does not require oxygen
anaerobic
The amount of energy needed to raise the temperature of 1 gram of water by 1 degree Celsius
calorie
Cellular respiration begins with a pathway called ______, which takes place in the ______ of the cell
glycolysis; cytoplasm
The transfer of high-energy electrons down the electron transport chain causes ____ to be transported across the mitochondrial membrane.
hydrogen ions
In eukaryotes, the electron transport chain is composed of a series of electron carriers located in the _______ of the mitochondrion.
inner membrane
A Calorie is also reffered to as a ______
kilocarlorie
In the matrix, pyruvic acid is converted to _____ acid before the Krebs cycle begins.
lactic
innermost compartment of the mitochondrion
matrix
The pyruvic acid produced in glycolysis enters the _______ if oxygen is present in a cell.
mitochondria.
Cellular respiration continues in the _____ of the cell with the _ and electron transport chain.
mitochondria; Krebs cycle
The energy flow in photosynthesis and cellular respiration occurs in the ____ direction
opposite
Cellular respiration removes ______ from the air.
oxygen
ATP synthases produce the force needed to add one ____ to each ADP molecule by spinning when hydroen ions flow through thm
phosphate group
