Exam 2

Which energy pathway connects all living organisms?

Glycolysis

What is the function of the two membranes of mitochondria?

Protons are pumped into the space between the membranes.

The CFTR receptor moves chloride ions out of a cell by active transport. This is an example of

a reaction requiring the input of energy (ATP).

Plants require energy from light to perform photosynthesis in which glucose is formed from carbon dioxide and water. This is an example of

a reaction that takes up energy.

If you were working with a 3D model of an enzyme, and you had found a part representing a molecule that fits into the active site, you would have found something that is

a substrate.

Active transport is different from simple diffusion because active transport

all answers are correct

The region of an enzyme that catalyzes reactions is called

an active site.

Phagocytosis is

an example of endocytosis.

if you measure the air a person has inhaled and exhaled, you will find that the concentrations have ______ in the exhaled air.

lower O2 concentrations and higher CO2 concentrations

Enzymes speed chemical reactions by

lowering the energy required to start a chemical reaction.

In animal cells, the primary organelle that generates molecules of ATP is the

mitochondrion

The Krebs cycle occurs in the

mitochondrion

The electron transport chain occurs in the

mitochondrion

Simple diffusion

moves molecules against a concentration gradient.

animals are

net O2 consumers and CO2 producers.

Plants are

net O2 producers and CO2 consumers.

Noncompetitive inhibition of enzymes

occurs when a substance binds to an enzyme at a site away from the active site.

Competitive inhibition of enzymes

occurs when a substance other than the correct substrate binds at the active site of an enzyme

The diffusion of water across a selectively permeable membrane is

osmosis.

In glycolysis and the Krebs cycle, electrons are removed from glucose and taken up by molecules like NAD+. In such a reaction, glucose is being _____ and NAD+ is being ____.

oxidized, reduced

When electrons are removed from a food molecule, the molecule is

oxidized.

If you were observing mud from the bottom of a pond, you would expect to see glycolysis since it does not require

oxygen

The "spent" electrons from the electron transport chain in aerobic respiration are transferred to

oxygen

A ball at the top of a hill is an example of ______ and a ball rolling down the hill is an example of ______.

potential energy; kinetic energy

Glycolysis of a glucose molecule

produces a net gain of two molecules of ATP

The electron transport chain produces a(n) _____________ gradient.

proton

A variety of carbohydrates, proteins, and fats in a diet

provides many molecules that can enter aerobic respiration at different stages.

The net ATP production in glycolysis is only two because

two molecules of ATP are needed to "activate" glucose.

If a cell contains 95% water in its cytoplasm and the environment surrounding the cell contains 90% water

water will flow out of the cell by osmosis.

In glycolysis, the net number of NADH produced is

2

The theoretical net ATP yield from a molecule of glucose is ______ ATP molecules.

36

The Krebs cycle produces ______, ______, and carbon dioxide.

ATP, electron carriers

Cells use energy for which of the following?

All of the answers are correct.

The chemical formula for glucose is

C6H12O6

The electrons that are transferred during cellular respiration are carried in the molecules

NADH and FADH2.

A cell produces approximately 30 ATP per glucose molecule. However, if you calculated the total energy in a glucose molecule, 90 ATP should be generated. What is the best explanation for this difference?

Some energy is lost as heat.

If you were looking for signs of cellular respiration, you could do tests for the production of

carbon dioxide, water, and ATP.

Examples of potential energy include

chemical bonds and concentration gradients

If asked to point on a diagram of a cell to the place where glycolysis occurs, you would plant to the

cytoplasm.

Cyanide and carbon monoxide block the final step in the electron transport chain. What effect would this have on ATP production in the mitochondria?

decreased ATP, because electrons would not be able to move through the electron transport chain

Entropy is

disorder

Which of the following are examples of potential energy?

electrons in chemical bonds, proton gradient, ATP

Which of the following are examples of kinetic energy?

electrons moving through the electron transport chain, protons moving through ATP synthase

When NaCl (table salt) forms, sodium (Na) loses energy by ______ and chlorine (Cl) gains energy by _____

giving up an electron in oxidation; gaining an electron in reduction

The reactants for cellular respiration are

glucose and oxygen

The three main biochemical pathways of cellular respiration are

glycolysis, Krebs cycle, and electron transport chain.

The only source of ATP production in cells relying fermentation is

glycolysis.

If you radioactively labelled NADH and FADH2, you would observe that the radioactivity would be transported at the

inner mitochondrial membrane.

The main reason that cellular respiration needs to occur step by step is because

it enables cells to harness energy released at each step.

What is the role of oxygen in respiration?

it is reduced at the end of the electron transport chain, forming water.

The energy source that powers photosynthesis is

sunlight

In which case is the energy involved farthest from being kinetic energy?

the energy in chemical bonds

Reduction means

the gain of electrons by an atom or molecule.

Oxidation means

the loss of electrons from an atom or molecule.

Oxidation-reduction reactions

transfer electrons from one molecule to another.