Mastering Bio Chapter 6

Cellular respiration accomplishes two major processes: (1) it breaks glucose down into smaller molecules, and (2) it harvests the chemical energy released and stores it in ATP molecules. By the end of _____, the breakdown of glucose is complete; most ATP molecules are produced during _____.

the Citric Acid cycle ... electron transport

NADH and FADH2 are important in cellular respiration because they deliver high-energy electrons to the electron transport system. Electron transport produces _____ ATP molecule(s) per NADH molecule and _____ ATP molecules(s) per FADH2 molecule.

three ... two

In electron transport, high-energy electrons "fall" to oxygen through a series of reactions. The energy released is used to _____.

transport protons into the inter membrane space of the mitochondria, where they become concentrated. They then flow back out into the the inner compartment (matrix) of the mitochondria. On the way back, protons turn ATP synthase turbines and produce ATP.

Which of these is NOT a product of the citric acid cycle (also called the Krebs cycle)?

acetyl CoA

The enzyme ATP synthase catalyzes the phosphorylation of ADP to form ATP. In eukaryotic cells, the energy needed for this endergonic reaction is derived from _____.

the movement of hydrogen ions across the mitochondrial membrane

The energy production per glucose molecule through the citric acid cycle is _____.

2 ATP, 6 NADH, 2 FADH2

Substrate-level phosphorylation directly generates ATP during a chemical reaction. As a single molecule of glucose is completely oxidized in the presence of oxygen, how many molecules of ATP are made by substrate-level phosphorylation?

4 ATP

The overall efficiency of respiration is approximately _____.

40%

In glycolysis, what starts the process of glucose breakdown?

ATP

Monosaccharides __________, and polysaccharides __________.

are single monomer units; are made of many monosaccharides chained together

Unlike the Citric Acid cycle and electron transport, glycolysis occurs _____.

in the cytoplasm

Where does glycolysis occur in a eukaryotic cell?

in the cytoplasmic fluid

In eukaryotes, most of the high-energy electrons released from glucose by cell respiration _____.

reduce NAD+ to NADH, which then delivers them to the electron transport chain

In glycolysis there is a net gain of _____ ATP.

2

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

10

How many NADH are produced by glycolysis?

2

Lungs are to breathing as _____ are to cellular respiration.

mitochondria

Which of these is NOT a product of glycolysis?

FADH2 (Product of Citric Acid Cycle)

In the video, what is the primary sugar being pulled out of the hole high in the tree?

Glucose

Where does Glycolysis occur?

In the cytosol

Where and what does the Citric acid cycle do?

In the mitochondrial matrix and transfers electrons to NADH and FADH2

______ are the sites of cellular respiration.

Mitochondria

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

NADH and FADH2 ... inter membrane space

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

NADH; NAD+

__________ is to a mitochondrion as __________ is to a chloroplast

O2 ... CO2

The final electron acceptor of cellular respiration is _____.

Oxygen

Which part(s) of cellular respiration require(s) oxygen gas?

The citric acid cycle and the electron transport chain

What is oxygen?

The final electron acceptor of cellular respiration

Which of the following is the source of the energy that produces the chemiosmotic gradient in mitochondria?

electrons

The function of cellular respiration is to _____.

extract usable energy from glucose

Glycolysis is the multi-step breakdown of _____. Several different _____ play a role in this process.

glucose ... enzymes

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

The proximate (immediate) source of energy for oxidative phosphorylation is _____.

kinetic energy that is released as hydrogen ions diffuse down their concentration gradient

In muscle cells, fermentation produces _____.

lactate and NAD+

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

loses ... oxygen gains

Primarily, cellular respiration serves to _____.

make ATP to power the cell's activities

What is/are the most important output(s) of glycolysis?

two pyruvic acid and two NADH molecules

______ and ________ are byproducts of cellular respiration

Carbon dioxide and water

What are the sites of photosynthesis?

Chloroplasts

What is the role of oxygen in cellular respiration?

Oxygen accepts high-energy electrons after they are stripped from glucose.

Cellular respiration requires fuel (glucose) and oxygen gas. The main process that produces these inputs is _____.

Photosynthesis

What does photosynthesis produce?

Produces glucose and releases oxygen into the atmosphere

Which of the following best describes the electron transport chain?

Electrons pass from one carrier to another, releasing a little energy at each step.

In glycolysis, ATP molecules are produced by _____.

Substrate-level phosphorylation

Which part(s) of cellular respiration take(s) place in the mitochondria?

The Citric Acid cycle and the electron transport chain

Which of these enters the citric acid cycle (also called the Krebs cycle)?

acetyl CoA

What two-carbon precursor molecule from carbohydrate metabolism is used to produce fatty acids?

acetyl-CoA

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

oxidative phosphorylation

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 the citric acid cycle (also called the Krebs cycle), ATP molecules are produced by _____.

substrate-level phosphorylation

Where do the reactions of the citric acid cycle occur in eukaryotic cells?

the mitochondrion

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