Biology chapter 6

Which of the following statements regarding the chemical grooming of pyruvate is false?

Each pyruvate molecule has a CO2 added and then joins with an NADH

A muscle cell deprived of molecular oxygen will convert glucose to lactic acid to __________.

Recycle NADH through fermentation

The proximate source of energy for oxidative phosphorylation is_____.

Kinetic energy that is released as hydrogen ions diffuse down their concentration gradients

Sports physiologists at an Olympic training center want to monitor athletes to determine at what point their muscles begin to function anaerobically. They could do this by checking for a buildup of _____.

Lactic Acid

A scientist wants to study the enzymes of the citric acid cycle in eukaryotic cells. What part of the cell should she use as a source of these enzymes?

Mitochondrial matrix

Given the relatively modest number of calories burned by anything but the most vigorous activities, why can people consume over 2000 kg calories a day, yet maintain a healthy body weight?

Most of the energy consumed in food is spent maintaining the body's functions, so only a fraction of food energy needs to be burned in exercise.

In cellular respiration, organic molecules become oxidized as ____ picks up electrons and H+ and becomes reduced to NADH

NAD+

During electron transport, energy from _____ is used to pump hydrogen ions into the _____.

NADH and FADH2 ... intermembrane space

During fermentation, __________ that was produced during glycolysis is converted back to __________.

NADH; NAD+

In the electron transport chain, the final electron acceptor is

Oxygen

NADH delivers electrons to an electron transport chain, which passes the electrons through carrier molecules in a series of Reddox reactions to the final electron acceptor, ____

Oxygen

The final electron acceptor of cellular respiration is _____.

Oxygen

For each glucose that enters glycolysis, _____ NADH Enter the electron transport chain

10

How many molecules of NADH are produced during one round of glycolysis?

2

In glycolysis there is a net gain of _____ ATP

2

The label on the box of the breakfast cereal lists one serving as "200 calories" per serving. How many calories are actually in one serving?

200,000

How many NADH are produced by glycolysis?

two

In glycolysis, what starts the process of glucose breakdown?

ATP

The energy released from the redox reactions in the electron transport chain is used by the cell to make ____

ATP

Which of these and where use the citric acid cycle also called the Krebs cycle?

Acetyl CoA

Which of these is not a product of the citric acid cycle also called the Krebs cycle?

Acetyl CoA

Why is the citric acid cycle called a cycle?

Acetyl CoA binds to oxaloacetate and this compound is restored at the end of the cycle.

Which of the following processes produces the most ATP per molecule of glucose oxidized?

Aerobic respiration

In an experiment, mice were fed glucose (C6H12O6) containing a small amount of radioactive carbon. The mice were closely monitored, and after a few minutes radioactive carbon atoms showed up in __________.

Carbon dioxide

The O2 required for __________ is supplied by __________.

Cellular respiration....breathing

Which of these is not a product of glycolysis?

FADH2; from Citrix acid cycle

Each turn of the citric acid cycle generates 1 ATP and ______ additional energy rich molecules ____.

Four; 3 NADH and 1 FADH2

During cellular respiration, glucose is oxidized. However, an intermediate, _____, can be siphoned off and used to synthesize fats.

G3P

Which stage of cellular respiration appears to have evolved first?

Glycolysis

Marathon runners are long-distance runners (marathons are races that are 26.2 miles long). Studies have shown that the muscles of marathon runners contain an abundance of slow-twitch muscle cells. Which of the following statements about these fibers is true?

Slow-twitch fibers have lots of mitochondria to make ATP aerobically.

What is the ultimate fate of the electron's that are stripped from glucose during cellular respiration?

They are used to form water

How do cells capture the energy released during cellular respiration?

They produce ATP.

A friend tells you that he is going on a low-carb diet to lose weight because he thinks that carbs contain more energy than fats or protein. What would you tell your friend about his plan?

This is a bad idea because fats contain more hydrogen atoms then carbohydrates and protein.

The function of coenzyme A in the citric acid cycle is most like

a limousine driver dropping off a couple at the school prom

Besides sugars and fats, organisms can use other molecules as fuel for cellular respiration. When protein molecules are used, _____ are produced as waste.

amino groups

When proteins are used as a source of energy for the body, the proteins

are converted mainly into intermediates of glycolysis or the citric acid cycle

Which of the following is a result of glycolysis?

conversion of glucose to two three-carbon compounds

The transfer of ____ from one molecule to another is an oxidation reduction reaction, or redox reaction

electrons

When a cell uses fatty acids for aerobic respiration, it first hydrolyzes fats to

glycerol and fatty acids

A chemist has discovered a drug that blocks phosphoglucoisomerase, an enzyme that catalyzes the second reaction in glycolysis. He wants to use the drug to kill bacteria in people with infections. However, he cannot do this because __________.

human cells must also perform glycolysis; the drug might also poison them

Where does glycolysis occur in a eukaryotic cell?

in the cytoplasmic fluid

When a car engine burns gasoline, the results of the reaction are similar to when cells burn glucose. Both reactions release carbon dioxide and water. In cells, the chemical energy in food is converted to ATP and heat. In a moving car, the chemical energy in gasoline is converted to _____.

kinetic energy and heat

In cellular respiration, glucose ____ electrons, whereas ____ electrons.

loses ... oxygen gains

Oxidation is the ________, and reduction is the ________.

loss of electrons; gain of electrons

Some friends are trying to make wine in their basement. They've added yeast to a sweet grape juice mixture and have allowed the yeast to grow. After several days they find that sugar levels in the grape juice have dropped, but there's no alcohol in the mixture. The most likely explanation is that the

mixture needs less oxygen because yeasts only produce alcohol in the absence of oxygen

A child is born with a rare disease in which mitochondria are missing from skeletal muscle cells. However, the muscles still function. Physicians find that the

muscle contains large amounts of lactate following even mild physical exercise

Bacteria that are unable to survive in the presence of oxygen are called

obligate anaerobes

In cellular respiration, most ATP molecules are produced by ____.

oxidative phosphorylation

In cellular respiration, glucose becomes ____ to carbon dioxide as it loses electrons (hydrogen atoms)

oxidized

Bacteria have no membrane-enclosed organelles. However, some still generate ATP through cellular respiration. Where is the electron transport chain found in these organisms?

plasma membrane

In oxidative phosphorylation, electrons are passed from one electron carrier to another. The energy released is used to ____.

pump protons (H+) across the mitochondrial membrane

After glycolysis but before the citric acid cycle,

pyruvate is oxidized

In cellular respiration, oxygen becomes ____ to water as it gains electrons (in hydrogen atoms) that came from glucose.

reduced

In glycolysis, ATP molecules are produced by _____.

substrate-level phosphorylation

In the citric acid cycle also called the Krebs cycle, ATP molecules are produced by ____.

substrate-level phosphorylation

Fat is the most efficient molecule for long-term energy storage, even compared to carbohydrates, because __________.

with their numerous hydrogen atoms, fats provide an abundant source of high-energy electrons