Chapter 10 (HW)

term that refers to all chemical reactions and physical workings of the cell is

metabolism

A biological catalyst, that increases the rate of a chemical reaction without being consumed in the reaction, is called a(n)

enzymes

A catalyst ______ the rate of a reaction ____________.

speeds up; without being consumed by the reaction

The minimum amount of energy required for a reaction to proceed is termed the

activation energy

A specific molecule on which an enzyme acts is a(n

substrate

Metabolism includes ______ chemical reactions and all physical workings of the cell.

all

Composed principally of amino acids,____________ , facilitating metabolic activities of the cell.

enzymes act as biological catalysts

An enzyme acts as a ______ that alters the rate of a reaction without being changed by the reaction.

catalysts

What term refers to a biological catalyst that lacks an essential cofactor?

apoenzyme

Activation energy is the amount of energy ______ a chemical reaction

needed to initiate

A substrate is ______ in an enzyme-catalyzed reaction.

a reactant

For an apoenzyme to become a functional holoenzyme, it must ______

bind to a cofactor

The minimum amount of energy required for a reaction to proceed is termed the ____________ energy

activation

Metals are _______ cofactors

inorganic

An enzyme with its apoenzyme and cofactors is referred to as a(n) ,______________ or a conjugated enzyme.

holoenzyme

Enzymes ______  active site(s)

can have more than one

An organic or inorganic enzyme accessory, that binds to an apoenzyme to form a holoenzyme, is a(n) ______

cofactor

The active site of an enzyme is also known as the ______

catalytic site

Which identifies the correct relationship among components of coenzymes?

Coenzymes = organic / Metals = inorganic

An enzyme can only bind to specific substrates because of the ______.

shape of its active site

Which model is sometimes used to describe enzyme-substrate interactions?

lock-and-key

what term also used to describe catalytic site

an active site

Which best defines an active site?

Region of an enzyme where the substrate binds

coenzymes can act as what carriers?

electron carriers

An enzyme's active site has a unique structure that binds to a specific substrate.

True

When a molecular mimic competes with the normal substrate for the active site of an enzyme, the enzyme is effectively shut down. This form of inhibition is termed

competitive inhibition

A reaction that releases free energy as it goes forward is a

exergonic reaction

Which describes the primary function of a coenzyme?

Transient carrier of electrons or chemical groups in reactions

Enzymes involved in cellular redox reactions have coenzyme carriers called ______ and ______

NAD, FAD

NAD

nicotine adenine dinucleotide

FAD

flavin adenine dinucleotide

In competitive inhibition, the molecular mimic competes for the ______ of an enzyme.

active site

The letters in ATP represent the words

adenosine triphosphate

During exergonic reactions, energy is ______ as the reaction goes forward.

released

In metabolism, catabolic reactions are the source of ______ used by anabolic reactions.

precursor molecules

NAD and FAD are included in what kind of electron carriers?

Common electron carriers

series of reactions that relies on free oxygen, converts glucose to CO2, and allows cells to recover significant amounts of energy in the form of ATP is known as

aerobic respiration

Coenzymes are inorganic cofactors.

false

In aerobic respiration, ______ serves as the final electron acceptor

oxygen

what is the typical "next step" for pyruvate at the end of glycolysis following normal aerobic or anaerobic respiration?

Krebs cycle

The Krebs cycle occurs in the ______ of eukaryotic cells and the ______ of bacteria.

mitochondria; cytoplasm

Precursor molecules are required for ______ reactions that build larger, more complex molecules. These precursors are generated by ______ reactions that break down large organic molecules.

anabolism, catabolism

Aerobic respiration includes the following three pathways:

• respiratory chain.

• glycolysis.

• Krebs cycle.

In strict aerobes and some anaerobes, pyruvic acid enters the Krebs cycle after it is converted to acetyl CoA.

True

The location of the Krebs cycle enzymes in eukaryotes is in the ______ matrix, while in prokaryotes the enzymes are found in the ______.

mitochondrial, cytosol

For each glucose molecule that enters glycolysis, what is the maximum number of ATP molecules that can be produced by oxidative phosphorylation? 

34

Both aerobic and anaerobic respiration use free oxygen as the final electron acceptor.

false

Which term describes the incomplete breakdown of glucose due the absence of an electron acceptor for the electron transport system?

fermentation

The final step in the electron transport chain produces ______.

water

During aerobic respiration of one molecule of glucose, a maximum of 34 ATPs are generated by ______ phosphorylation in the electron transport system.

oxidative

Which of the following enzymes catalyzes the separation of fatty acids from glycerol in a triglyceride?

lipase

Oxygen-containing ions, such as nitrate and nitrite, are used as the final electron acceptors in ______ respiration

anaerobic

Amphibolism is ______.

the integration of catabolic and anabolic pathways

Autotrophs can synthesize all macromolecules from carbon dioxide and minerals.

true

Anabolic processes allow a prokaryotic cell to double its contents prior to dividing through

binary fission

he property of a system to integrate catabolic and anabolic pathways, as when products of catabolic pathways become intermediates entering anabolic pathways, is called

amphibolism

Which of the following can synthesize all the macromolecules needed by the cell from CO₂ and minerals?

Autotrophs

The sun provides energy ______.

directly or indirectly to most organisms

Which pigment is at the center of a photosystem?

Chlorophyll

Before a bacterial cell ____________, anabolic processes must produce sufficient macromolecules to serve two cells.

divide by binary fission

The Calvin cycle is ______.

dependent on the products from the light-dependent reactions to work

What term is used to describe photosynthesis reactions which release oxygen as a product?

oxygenic

The ultimate source of almost all chemical energy on Earth is the ______ , making most organisms directly or indirectly dependent on photosynthesis.

sun

both photosystem I and photosystem II contain ____________ chlorophyll

green pigment

The Calvin cycle is part of the light-dependent reactions of photosynthesis.

false