A&P Chapter 4
A part of a gene that is a DNA sequence 333 nucleotides long encodes _________ amino acids.
111
How many codons specify the twenty types of amino acids?
61
List the end products of the complete oxidation of one molecule of glucose.
6CO2, 6H2O, 32 ATP
If one strand of DNA has the sequence TCAGGCTATTCCCG, then the complementary sequence of the other strand is
AGTCCGATAAGGGC
A molecule that carries energy in a form the cell can use is
ATP
Name the molecule that is common to carbohydrate and lipid metabolic pathways and connects these two pathways metabolically.
Acetyl coenzyme A
What is the name of the three letter sequences being "read" during translation? tRNA rRNA mRNA All three types of RNA are involved in protein synthesis.
All three types of RNA are involved in protein synthesis.
Decide whether each label describes anabolism or catabolism, then drop each into the correct box. Production of glycogen Oxidation of glucose Requires energy Releases energy Dehydration synthesis Hydrolysis
Anabolism Catabolism Production of glycogen Oxidation of glucose Requires energy Releases energy Dehydration synthesis Hydrolysis
The amino acids from proteins and the glycerol and fatty acids from fats can be "burned" to yield ATP using the cellular respiration pathways. However, these nutrient molecules do not go through glycolysis first. Indicate the various points along the cellular respiration pathway that these molecules can enter. (There are multiple answers.) As pyruvic acid As acetyl CoA As water As glucose As a citric acid cycle intermediate
As pyruvic acid As acetyl CoA As a citric acid cycle intermediate
What is the waste product of the Krebs cycle?
CO2
Occurs in mitochondria; products are 2 CO2 and 1 ATP per substrate molecule
Citric acid cycle
What is the name of the three letter sequences being "read" during translation?
Codon
Which molecules generate the proton gradient across the mitochondrial membrane?
Cofactor molecules that where reduced during glycolysis and the Krebs cycle
Using "E" for enzyme, "S" for substrate, and "P" for product, indicate the best representation of the mechanism of enzyme function.
E + S → ES → EP → E + P
Occurs in mitochondria; products are water and 26-28 ATP
Electron transport chain
The portion of the entire DNA base sequence that actually codes for protein production.
Exam
During cellular respiration, hydrogen and high-energy electrons are picked up by carriers. List these carriers. (Check all that apply.) FAD NAD Lactic acid ATP
FAD NAD
T/F: An active site is the part of a substrate molecule that binds an enzyme.
False
T/F: An enzyme speeds up a chemical reaction in the cell, but can only be used once.
False
T/F: Each mRNA molecule is used to produce one copy of a polypeptide molecule.
False
T/F: Genetic information is contained in protein molecules and is passed from one parent to another.
False
T/F: Hydrogen ions want to move from the intermembrane space to the mitochondrial matrix because of an osmotic pressure gradient.
False
Segment of DNA that codes for a protein, mRNA, or tRNA
Gene
The sequence of nucleotide bases that determines the sequence of amino acids in a protein.
Genetic code
The complete set of genetic instructions for a cell/organism.
Genome
Occurs in cytoplasm; net products are 2 ATP and 2 pyruvic acid molecules
Glycolysis
Three metabolic pathways are involved in the breakdown of glucose to CO2, H2O, and ATP. Of the three, which one occurs in the cytoplasm? Citric acid cycle Electron transport chain Glycolysis
Glycolysis
During cellular respiration reactions, NAD and FAD pick up hydrogens and high-energy electrons during which phases of the pathway? (Check all that apply.) Glycolysis Citric acid cycle Electron transport chain
Glycolysis Citric acid cycle
For each descriptive item, match it with the correct cellular respiration pathway. Labels can be used more than once. Uses 2 ATP, produces 4 ATP Acetyl CoA enters pathway Pyruvic acid as product Uses NADH+H Produces NADH+H Glucose as substrate Requires oxygen Produces 28 ATP
Glycolysis Citric acid cycle Electron transport chain Uses 2 ATP, produces 4 ATP Acetyl CoA enters pathway Pyruvic acid as product Uses NADH+H Produces NADH+H Glucose as substrate Requires oxygen Produces 28 ATP
Which product of glucose breakdown has the most energy associated with it? Carbon dioxide Hydrogen plus its electrons Water
Hydrogen plus its electrons
Where does transcription occur?
In the nucleus
Which of the following is true? An amino acid encodes a gene. DNA has five types of nucleotide bases. Much of the genome does not encode proteins. The genome consists of entirely protein-encoding genes.
Much of the genome does not encode proteins.
DNA is a double helix, with a structure much like a twisted ladder. What forms the "rungs" of the ladder?
Nitrogenous bases
If you were to sequence the genome of two individuals and found that their DNA is 99.9% similar, what inference could you make?
No inferences could be made because 99.9% of DNA is shared between all humans.
What is a cofactor?
Nonprotein molecule that must combine with some enzymes in order for them to become active
At the completion of DNA replication, how much of each new DNA molecule is conserved?
One-half of each DNA molecule is conserved
Almost all enzymes are what class of organic molecule?
Proteins
What is the end product of glycolysis during aerobic conditions?
Pyruvate
Classify each characteristic as describing either DNA or RNA. Single stranded Double stranded Deoxyribose Adenine, cytosine, guanine, uracil Is "read" in cytoplasm Adenine, cytosine, guanine, thymine Is "read" in nucleus Ribose as sugar
RNA DNA Single stranded Double stranded Deoxyribose as sugar Adenine, cytosine, guanine, uracil Is "read" in cytoplasm Adenine, cytosine, guanine, thymine Is "read" in nucleus Ribose as sugar
Which DNA sequence can encode the amino acid sequence ile-asp-ser-cys-his-tyr? TAACTAAGTACGGTGATG All of the answer choices are correct TAACTGTCGACGGTGATG TAGCTGTCAACAGTGATA
TAACTAAGTACGGTGATG
What binds to the active site of an enzyme?
The substrate
What is the function of ATP molecules in living cells?
They capture energy from the oxidation of fuels in their high-energy phosphate bonds, and the energy is used in various cell processes.
Complete the sentences describing the process by which DNA strands are copied. Then rearrange the sentences (starting with the reference to the figure), placing them in logical order. As the DNA uncoils, _____ are exposed, providing a template for building new DNA strands. The enzyme called _____ brings in DNA nucleotides that contain the base that is _____ the exposed base. The result of this process is _____ new DNA double helices, each consisting of one original strand and one new strand. This figure shows the process of _____ that occurs prior to cell division.
This figure shows the process of DNA replication that occurs prior to cell division. As the DNA uncoils, nitrogenous bases are exposed, providing a template for building new DNA strands. The enzyme called DNA polymerase brings in DNA nucleotides that contain the base that is complementary to the exposed base. The result of this process is two new DNA double helices, each consisting of one original strand and one new strand.
Match each type of nucleic acid with the process(es) it is involved with. Labels can be used more than once. rRNA mRNA tRNA DNA
Transcription Translation rRNA mRNA tRNA DNA
T/F: A example of genetic change is the presence of certain DNA sequences occurring in different numbers of copies in different individuals.
True
T/F: A mutation that changes a CGC codon to CGA would not affect health because the encoded amino acid is unchanged.
True
T/F: All of the genetic information in a cell is a genome.
True
T/F: An ATP molecule consists of an adenine, a ribose, and three phosphates.
True
T/F: The electron transport chain is a series of enzyme complexes that pass electrons one-to-another, releasing energy that is used to phosphorylate ADP to ATP on the inner mitochondrial membrane.
True
T/F: The part of the tRNA that binds mRNA is the anticodon.
True
How many cycles does the Krebs cycle complete in order to completely break down two pyruvate molecules?
Two
A DNA sequence AACGGTGCACCACGG encodes an mRNA of sequence
UUGCCACGUGGUGCC
A mutation is
a change in a DNA sequence in less than 1% of a population that affects anatomy and/or physiology.
A cofactor is ______. Examples are _____.
a necessary part of some enzymes; copper, iron, and zinc
The pyruvic acid molecules then enter the mitochondria of the cell where they are converted to _____ by losing a carbon dioxide molecule.
acetyl CoA
Humans require vitamins in their diets because these nutrients
act as coenzymes
When catalyzing a metabolic reaction, the role of an enzyme is to reduce the __________.
activation energy
During the metabolism of glucose, carbon dioxide (CO2) is produced during the __________ reactions.
aerobic
The term metabolism refers to
all of the chemical reactions in a cell
Chemical reactions in which large molecules are built from small molecules are classified as __________ reactions. In contrast, __________ reactions involve breaking large molecules down into smaller ones.
anabolic; catabolic
Synthesis of a protein stops when
any of three "stop" codons are encountered in the mRNA.
During the citric acid cycle, the carbons that remain from the original glucose split off as _____. During each cycle, one ATP is made.
carbon dioxide
In the citric acid cycle,
carbon dioxide is released.
The term catabolism refers to
chemical reactions that release energy
The anaerobic reactions of cellular respiration take place in the
cytoplasm
The anaerobic reactions of cellular respiration occur in the __________ , whereas the aerobic reactions of cellular respiration occur in the __________ .
cytoplasm without O2 required; mitochondria with O2 required
The carrier molecule delivers high-energy electrons to the series of enzymes called the _____. As the electrons pass along these enzymes, their energy is used to make _____.
electron transport chain ; ATP
Throughout both glycolysis and the citric acid cycle, hydrogen atoms and high-energy _____ are released. They are picked up by a carrier molecule.
electrons
In cellular respiration,
energy is released from molecules and is transferred to other molecules.
Each chemical reaction within a pathway is catalyzed by a specific _____, without which the reaction would not occur.
enzyme
A molecule that is a storage form of carbohydrate is
glycogen
Within the cytoplasm, glucose enters a series of anaerobic reactions called _____, producing two 3-carbon compounds called _____.
glycolysis ; pyruvic acid
The enzyme catalase acts on the substrate
hydrogen peroxide
This enzyme is available in _____ quantity, therefore it can become _____ as substrate concentration increases.
limited ; saturated
Metabolic pathways are often _____, with a compound from one pathway entering another.
linked
Dehydration synthesis reactions __________ , whereas hydrolysis reactions __________ .
lose H2O as bonds are formed; use H2O to break bonds
In what molecule are codons found?
mRNA
What occurs during the phase of protein synthesis called transcription?
mRNA is produced from a DNA template.
An example of an anabolic reaction is
many monosaccharides bonding, forming glycogen
What is the product of the reactions of transcription?
messenger RNA
In dehydration synthesis of a carbohydrate,
monosaccharides are joined.
The addition or deletion of nitrogenous bases during replication or transcription results in changes in the DNA sequence. The change in base sequence is called __________.
mutation
Three types of genetic changes are
mutations, SNPs, and changes in copy number.
Which choice lists structures in order of increasing size? genome - nucleus - chromosome - nucleotide - gene nitrogenous base - nucleotide - gene - chromosome - genome cell - organelle - tissue - organ nitrogenous base - nucleotide - gene - genome - chromosome
nitrogenous base - nucleotide - gene - chromosome - genome
Acetyl CoA then binds with _____ to form citric acid, beginning a series of reactions called the _____.
oxaloacetic acid ; citric acid cycle
Energy needed for cellular function comes from the "burning" or __________ of glucose, fats, and protein.
oxidation
At the end of the electron transport chain, the electrons and hydrogen combine with __________, the final electron acceptor.
oxygen
Chemical reactions in cells typically occur one after the other, in sequences called metabolic _____.
pathways
Within these reaction sequences, the _____ of one reaction become the _____ of the next reaction.
products ; reactants
ATP is important to cellular processes because it
provides energy for cellular work when the terminal, high-energy bond is broken.
The rate that a metabolic pathway (such as the one shown) proceeds depends upon the available amount of a particular enzyme in the pathway. This enzyme is called the _____ enzyme.
rate-limiting
ATP molecules provide energy for cellular activities by __________.
releasing the terminal phosphate group and the energy associated with the bond
In the DNA damage response,
repair enzymes replace mismatched nucleotides in DNA.
The genetic code is
the correspondence between a sequence of three DNA nucleotides and a specific amino acid
The "genetic code" determines the types of proteins made by a cell. The term "genetic code" refers to ___________.
three-base sequences in DNA that code for a particular amino acid
Copying DNA information into an mRNA molecule is called
transcription
Once this enzyme is saturated, the rate of function of this pathway reaches its maximum. The presence of a greater amount of substrate _____ increase the reaction rate.
will not