Deck 4: Cellular Metabolism

Question 1

An ATP molecule consists of an adenine,a ribose and three phosphates.

Answer 1

True

Question 2

A codon is a set of three nucleotides of an mRNA molecule that correspond to a particular amino acid.

Answer 2

True

Question 3

Oxidation is a process that forms bonds between the atoms of molecules.

Answer 3

False

Question 4

A genome is a section of DNA in which the nitrogenous base sequence encodes a specific sequence of amino acids.

Question 5

The anticodon sequence is part of a transfer RNA molecule.

Question 6

Catalysis is the speeding of a chemical reaction.

Question 7

Anabolism includes

A) the buildup of larger molecules from smaller ones,requiring energy.
B) all processes required to maintain life.
C) processes that decompose structures in cells.
D) the breakdown of larger molecules into smaller ones,releasing energy.
E) the taking in of proteins from the cell membrane.

Question 8

A metabolic pathway is a sequence of enzyme-catalyzed reactions.

Question 9

Genes carry information that instructs a cell to

A) make glycogen.
B) make specific proteins from amino acids.
C) use energy.
D) convert nucleic acids into proteins.
E) take in proteins from the cell membrane.

Question 10

The four nitrogenous bases in DNA are adenine,cytosine,guanine and uracil.

Question 11

Enzymes are nucleic acids that promote specific chemical reactions.

Question 12

Translation is the assembly of an amino acid chain according to the sequence of base triplets in a transfer RNA molecule.

Question 13

All mutations are harmful.

Question 14

Most metabolic processes use chemical energy.

Question 15

Cells burn glucose in a process called oxidation.

Question 16

Of the 38 molecules of ATP generated in one round of the reactions of cellular respiration,only two come from glycolysis.

Question 17

Complete oxidation of glucose results in nitrogen and water.

Question 18

A nonprotein component with which some enzymes must combine in order to be active is called a co-factor.

Question 19

Genes pass to the next generation in eggs and sperm.

Question 20

Special proteins called enzymes control the reactions of metabolism.

Question 21

Each enzyme acts only on a particular chemical called its

A) gene.
B) catalyst.
C) activator.
D) complement.
E) substrate.

Question 22

Which of the following describes the steps in the correct order for an enzyme-catalyzed reaction?

A) substrate,enzyme,enzyme-substrate complex,product+enzyme molecule
B) enzyme,substrate,product,enzyme-substrate complex+enzyme molecule
C) product,enzyme-substrate complex,enzyme,substrate+enzyme molecule
D) enzyme-substrate complex,enzyme,substrate,product+ enzyme molecule
E) enzyme,product,enzyme-product complex,substrate

Question 23

Cellular respiration occurs in three distinct,yet interconnected series of reactions.Which of the following gives the correct order of these reactions?

A) electron transport chain,glycolysis and citric acid cycle
B) glycolysis,electron transport chain and citric acid cycle
C) citric acid cycle,glycolysis and electron transport chain
D) glycolysis,citric acid cycle and electron transport chain
E) electron transport chain,citric acid cycle,glycolysis

Question 24

In dehydration synthesis

A) larger molecules are decomposed into smaller ones.
B) monosaccharides are joined.
C) water molecules become joined to monosaccharide molecules.
D) the molecule is decomposed into carbon dioxide and water.
E) a person develops constipation.

Question 25

A piece of bread held in the mouth begins to taste sweet as large carbohydrate molecules are broken down into smaller sugars.These reactions are examples of

A) DNA guiding the production of a particular protein.
B) dehydration synthesis.
C) anabolism.
D) DNA synthesis.
E) catabolism.

Question 26

A sucrose molecule decomposing to yield a glucose molecule and a fructose molecule

A) is an example of dehydration synthesis.
B) releases a water molecule.
C) uses a water molecule.
D) only occurs if a person follows a high carbohydrate diet.
E) can also decompose to yield two glucose molecules.

Question 27

The part of an ATP molecule that holds the energy used in metabolism is

A) the sugar.
B) the nitrogen-containing base.
C) the phosphate bonds.
D) the amino acid.
E) the adenine.

Question 28

Glycolysis is referred to as the ____________ phase of cellular respiration because it does not require oxygen.

A) anaerobic
B) aerobic
C) probiotic
D) pyruvic
E) deoxygenic

Question 29

The active site of an enzyme is the part that

A) temporarily combines with the eventual product of an enzyme-catalyzed reaction.
B) temporarily combines with a specific part of the substrate,forming an enzyme-substrate complex.
C) temporarily combines with a specific part of another enzyme molecule to speed up an enzyme-catalyzed reaction.
D) helps to slow down an enzyme-catalyzed reaction.
E) must be frequently replaced.

Question 30

Enzymes

A) increase activation energy.
B) slow metabolic reactions.
C) are mostly nucleic acids.
D) do not change as they control reactions.
E) are consumed in reactions.

Question 31

Which of the following substances becomes more abundant during cellular respiration?

A) oxygen
B) glucose
C) sucrose
D) glycogen
E) ATP

Question 32

A protein that is altered by exposure to certain chemicals,heat,extremes of pH,electricity,or radiation is said to be

A) unnatural.
B) genetically modified.
C) denatured.
D) mutated.
E) reincarnated.

Question 33

An ATP molecule that loses its terminal phosphate becomes

A) AMP.
B) cyclic AMP.
C) a glucose molecule.
D) ADP.
E) an activated ATP.

Question 34

During the anaerobic phase of cellular respiration,one molecule of glucose

A) is broken down to yield two molecules of pyruvic acid.
B) combines with another to yield one molecule of pyruvic acid.
C) is converted into a molecule of pyruvic acid.
D) is broken down to yield one molecule of pyruvic acid and one molecule of lactic acid.
E) remains unchanged.

Question 35

An example of catabolism is

A) the formation of water.
B) hydrolysis.
C) dehydration synthesis.
D) two amino acids forming a dipeptide.
E) building a cell membrane.

Question 36

The part of an enzyme that combines with a specific part of the substrate is called the

A) passive site.
B) active site.
C) passive diffusion.
D) nucleus.
E) co-factor.

Question 37

The enzyme catalase acts on the substrate

A) oxygen.
B) hydrogen.
C) hydrogen peroxide.
D) peroxidase.
E) cholesterol.

Question 38

Anabolism and catabolism together constitute

A) metabolism.
B) protein synthesis.
C) dehydration synthesis.
D) hydrolysis.
E) digestion.

Question 39

Enzymes enable chemical reactions in organisms to proceed fast enough to sustain life by

A) raising the activation energy.
B) lowering the activation energy.
C) creating more efficient metabolic pathways.
D) bringing energy in the form of ATP molecules into cells.
E) sending ATP molecules out of cells.

Question 40

The reactions of anaerobic respiration occur in the

A) cytosol.
B) mitochondria.
C) nucleus.
D) Golgi apparatus.
E) vesicles.

Question 41

For each molecule of glucose that is decomposed completely,up to _______ molecules of ATP can be produced.

A) 34
B) 38
C) 25
D) 3
E) 100

Question 42

DNA replicates by

A) the double helix separating and pulling in new complementary bases.
B) creating an entirely new double helix.
C) exiting the cell and bringing in new DNA bases.
D) using RNA to manufacture protein molecules.
E) shattering into pieces that reproduce themselves and attach at random.

Question 43

A rate-limiting enzyme is typically the first enzyme in a series.This position is important because

A) if the reaction stops,the enzyme will have a chance to act.
B) the first enzyme is the fastest in the pathway.
C) the enzymes lose energy farther along the metabolic pathway.
D) a rate-limiting enzyme that acts later in the pathway could lead to build-up of an intermediate chemical.
E) the enzyme is destroyed farther along the pathway.

Question 44

The two molecules that enter the citric acid cycle are

A) two 3-carbon compounds and 38 ATPs.
B) a 4-carbon compound and an acetyl CoA.
C) a 2-carbon compound and 4-carbon acetyl CoA.
D) a pyruvic acid and a glucose.
E) a glucose and a fructose.

Question 45

The transfer of genetic information from the nucleus into the cytoplasm is a function of

A) DNA molecules.
B) ribosomal RNA.
C) messenger RNA.
D) transfer RNA.
E) the energy level of the cell.

Question 46

The organelle that houses the reactions of aerobic respiration is the

A) mitochondrion.
B) nucleus.
C) Golgi apparatus.
D) lysosome.
E) oxysome.

Question 47

The genetic code

A) is a sequence of amino acids that instructs cells how to make specific nucleic acids.
B) is a sequence of nucleic acid bases that instructs cells how to make specific protein molecules.
C) is the sequence of nucleus,rough ER,smooth ER,and the Golgi apparatus.
D) is a sequence of proteins embedded in the cell membrane.
E) is a sequence of amino acids and DNA bases.

Question 48

RNA molecules differ from DNA molecules in several ways.(choose the best answer. )

A) RNA molecules are single-stranded;their nucleotides include the sugar ribose and the nucleotide uracil.
B) RNA molecules are double-stranded;their nucleotides include the sugar ribose and the nucleotide uracil.
C) RNA molecules are single-stranded;their nucleotides include the sugar deoxyribose and the nucleotide uracil.
D) RNA molecules are double-stranded;their nucleotides include the sugar deoxyribose and the nucleotide uracil.
E) RNA molecules are triple-stranded;their nucleotides include the sugar glucose and the nucleotide uracil.

Question 49

During protein synthesis,amino acids are positioned in the proper sequence by molecules of

A) ribosomal RNA.
B) transfer RNA.
C) messenger RNA.
D) nuclear RNA.
E) DNA.

Question 50

The proportion of the human genome that encodes protein is about ________ percent.

A) 98
B) 50
C) 30
D) 10
E) 2

Question 51

All of the DNA in a cell constitutes the

A) gene.
B) nucleus.
C) amino acid code.
D) genome.
E) proteome.

Question 52

The parts of a DNA molecule that contain the genetic information for making particular proteins are the

A) nitrogenous bases.
B) sugars.
C) amino acids.
D) triglycerides.
E) phosphates.

Question 53

Copying of the information in DNA into RNA,which can exit the nucleus,is called

A) translation.
B) deamination.
C) transcription.
D) replication.
E) transduction.

Question 54

A DNA molecule

A) is twisted into a triple helix.
B) is composed of joined nucleotides.
C) is single-stranded.
D) contains RNA.
E) is globular shaped.