WorksheetsBiology Exam
Total questions: 245
Worksheet time: 61hrs 15mins
Translation occurs in the _____.
golgi
cytoplasm
lysosome
nucleus
A sequence of DNA reads ACTGAGTCA. The next base would have to be
T
C
A
G
any of those four bases
How do retroviruses such as HIV differ from other viruses?
They have much simpler reproductive cycles than other RNA viruses.
They can reproduce only inside living cells.
They contain the enzyme reverse transcriptase.
They contain DNA that is used as a template to make RNA.
Below are three statements. Which choice properly matches the statements with the correct biological processes?
I. This occurs in the nucleus of eukaryotic cells with DNA polymerase.
II. Transfer RNAs bind amino acids in the cytoplasm.
III. An RNA polymerase enzyme is required.
I: replication
II: transcription
III: replication
I: transcription
II: translation
III: translation
I: translation
II: translation
III: replication
I: replication
II: translation
III: transcription
Which of the following modifications of the primary RNA occurs in the nucleus of a eukaryotic cell?
All of these occur in the nucleus of a eukaryotic cell.
RNA splicing
Addition of a 3' tail
Addition of a 5' cap
You are a biochemist working for a pharmaceutical company. You have been tasked with identifying a sample of nucleic acid. It is determined that the sample contains the bases cytosine, guanine, adenine, and phosphate groups. Is the sample DNA or RNA?
RNA, the base guanine is unique to RNA
DNA, the base adenine is unique to DNA
Inconclusive, the listed components can be found in both DNA and RNA.
Replication of the following DNA strand: ACGTCGA would give what complementary strand?
(a)
The four bases contained in DNA are _____.
adenine, guanine, cytosine, thymine
adenine, guanine, purine, thymine
cytosine, guanine, thymine, uracil
adenine, guanine, uracil, thymine
A is the process where a gene in DNA is copied into RNA
Transcription
Translation
B is the process where mRNA is read to build a protein
Transcription
Translation
The flow of genetic information goes from RNA -> DNA -> protein.
True
False
A
Replication fork
DNA polymerase
Leading strand
Lagging strand
Ligase
B
Replication fork
DNA polymerase
Leading strand
Lagging strand
Ligase
C
Replication fork
DNA polymerase
Leading strand
Lagging strand
Ligase
D
Replication fork
DNA polymerase
Leading strand
Lagging strand
Ligase
E
Replication fork
DNA polymerase
Leading strand
Lagging strand
Ligase
Contains the nitrogenous base thymine
DNA
Nucleotides
Sugar-phosphate backbone
Polynucleotide
Gene
The monomers of nucleic acids
DNA
Nucleotides
Sugar-phosphate backbone
Polynucleotide
Gene
Formed by covalent bonds between nucleotides
DNA
Nucleotides
Sugar-phosphate backbone
Polynucleotide
Gene
A polymer of nucleotides
DNA
Nucleotides
Sugar-phosphate backbone
Polynucleotide
Gene
Information for building a polypeptide
DNA
Nucleotides
Sugar-phosphate backbone
Polynucleotide
Gene
Every polypeptide chain synthesized from mRNA starts with which amino acid?
Arginine
Phenylalanine
Methionine
Leucine
Ultraviolet (UV) radiation is damaging because it _____.
causes mutations in DNA
prevents DNA replication
deactivates enzymes needed for replication
prevents DNA transcription
In replication, why is the new DNA strand complementary to the 3' to 5' strands assembled in short segments?
it is more efficient than assembling complete new strands
DNA polymerase can assemble DNA only in the 3' to 5' direction
only short DNA sequences can extend off the RNA primers
the replication forks block the formation of longer strands
DNA polymerase can assemble DNA only in the 5' to 3' direction
Which statement about DNA replication is CORRECT?
DNA ligase helps assemble the leading strand.
The lagging strand is one of the strands of parental DNA.
The lagging strand is built continuously.
The leading strand is built continuously, and the lagging strand is built in pieces.
The leading strand is one of the strands of parental DNA.
Creates DNA by reading a template strand and adding nucleotides with complementary bases.
DNA polymerase
DNA ligase
Origin of replication
Replication bubble
DNA helicase
Bonds the DNA fragments of the lagging strand together.
DNA polymerase
DNA ligase
Origin of replication
Replication bubble
DNA helicase
The site of the start of DNA replication.
DNA polymerase
DNA ligase
Origin of replication
Replication bubble
DNA helicase
The site where DNA replication is occuring
DNA polymerase
DNA ligase
Origin of replication
Replication bubble
DNA helicase
Creates replication forks and replication bubbles
DNA polymerase
DNA ligase
Origin of replication
Replication bubble
DNA helicase
If a strand of DNA has the sequence AAGCTC, transcription will result in
a DNA strand with the sequence AAGCTC.
none of the above.
a single RNA strand with the sequence UUCGAG.
a single RNA strand with the sequence TTCGAG.
a DNA strand with the sequence TTCGAG.
The tRNA anticodon, CAG, is complementary to the mRNA codon with the sequence _____.
GTC
GUC
CAG
GAC
DNA replication is ______ in that you have one original strand and one new strand at the end of DNA replication. DNA replication is name of the process that synthesizes DNA.
fully conservative
nonconservative
semiconservative
Mutation (change) in a gene that altered the original codon to a stop codon would
result in a shorter polypeptide chain.
result in a polypeptide that is one amino acid shorter than the one produced before the mutation.
alter the location at which transcription of the next gene begins.
alter the reading frame.
result in an amino acid substitution.
A modification of the primary RNA, RNA splicing removes _______ from the mRNA while keeping the ______ .
backbone; bases
exons; introns
introns; exons
bases; backbone
Translation converts the information stored in _____ into _____.
protein; a polypeptide
DNA; RNA
RNA; a polypeptide
protein; DNA
Which of the following is not a component of a nucleotide?
A nitrogenous base
All of these are components of a nucleotide
A phosphate group
A pentose (five-carbon sugar)
Radioactively labeled bacteriophages were allowed to infect bacteria. In the first trial, the phages contained radioactive DNA, and radioactivity was detected in the bacteria. Next, other phages containing radioactive protein were allowed to infect bacteria, and radioactivity was not detected in the bacteria.
Hershey and Chase
Erwin Chargaff
Rosalind Franklin
Watson and Crick
The amount of A's = T's and C's = G's in a cell's DNA and different species have different amounts.
Hershey and Chase
Erwin Chargaff
Rosalind Franklin
Watson and Crick
Was the first to produced an X-ray image of DNA.
Hershey and Chase
Erwin Chargaff
Rosalind Franklin
Watson and Crick
Was the first to describe the structure of DNA as a spiral ladder with the bases forming the rungs and the sugar-phosphate the sides.
Hershey and Chase
Erwin Chargaff
Rosalind Franklin
Watson and Crick
What is the transcription product of the sequence GCTAGCGATGAC?
CGTUCGCUTCUG
CGAUCGCUACUG
CAGTAGCGATCG
CGUTCGCUTCUG
The directions for each amino acid in a polypeptide are indicated by a codon that consists of ________ nucleotides in an RNA molecule.
five
four
three
two
When one DNA molecule is copied to make two DNA molecules, the new DNA contains
none of the parent DNA.
50% of the parent DNA.
75% of the parent DNA.
100% of the parent DNA
If one strand of DNA is CGGTAC, then the corresponding strand would be
GCCTAG
GCCAUC
TAACGT
GCCATG
The transfer of genetic information from DNA to RNA is called
translation
transcription
initiation
elongation
Which of the following statements regarding a DNA double helix is true?
The amount of adenine is equal to the amount of uracil, and the amount of guanine is equal to the amount of cytosine.
The amount of adenine is equal to the amount of guanine, and the amount of thymine is equal to the amount of cytosine.
The amount of adenine is equal to the amount of cytosine, and the amount of guanine is equal to the amount of thymine.
The amount of adenine is equal to the amount of thymine, and the amount of guanine is equal to the amount of cytosine.
What nucleotide sequence would be found on the partner DNA strand of the strand shown?
ACTGT
UGAGA
TGACA
TGUGU
Which is the process that synthesizes mRNA, tRNA, or rRNA?
translation
transposition
transcription
transformation
The monomers of DNA and RNA are
monosaccharides
nucleotides
fatty acids
nucleic acids
Which of the following statements about eukaryotic RNA is true?
Introns are added to the RNA.
Exons are spliced together.
A small cap of extra nucleotides is added to both ends of the RNA.
The modified RNA molecule is transported into the nucleus.
Which of the following enzymes catalyzes the elongation of a new DNA strand?
helicase
ligase
single-stranded binding protein
DNA polymerase
Which of the following nucleotide bases is found only in RNA, not in DNA?
thymine
uracil
guanine
adenine
cytosine
A physical or chemical agent that changes the nucleotide sequence of DNA is called a/an
terminator
transpoon
mutagen
anticodon
Any change in the nucleotide sequence of DNA is called
a mutation
a mutagen
a base substitution
an anticodon
In the genetic code,
some codons specify more than one amino acid.
some codons consist of two nucleotides.
some amino acids are not specified by any codons.
many amino acids are specified by more than one codon.
In the Watson and Crick model of DNA, the "sides" of the ladder are composed of
thymine (T) and adenine (A).
cytosine (C) and thymine (T).
uracil (U) and adenine (A).
a sugar and a phosphate.
What is this molecule?
ACGCTAC
DNA
RNA
Protein
Multiple origins of replication on the DNA molecules of eukaryotic cells serve to
remove errors in DNA replication.
create multiple copies of the DNA molecule at the same time.
shorten the time necessary for DNA replication.
assure the correct orientation of the two strands in the newly growing double helix.
________ marks the end of a gene and causes transcription to stop.
a stop codon
RNA ligase
a terminator
methionine
Which of the following people conducted the experiments that demonstrated that DNA is the genetic material of bacteriophages?
Watson and Crick
Hershey and Chase
Franklin
Pauling
Embryonic stem cells differ from adult stem cells because they _____.
are capable of being fertilized
are capable of many cell divisions
can differentiate into all cell types
can differentiate into many cell types
________ are a major source of restriction enzymes.
Plant cells
Bacteria
Human cells
Reproductive cloning differs from therapeutic cloning by which of the following? (Select all that apply.)
Therapeutic cloning supplies cells for repair of damaged or diseased organs.
Reproductive cloning supplies cells for repair of damaged or diseased organs.
Reproductive cloning can result in the birth of a new living individual.
Therapeutic cloning use stem cells
The relationship between DNA and histones is most like
thread wrapped around a spool.
an egg yolk inside of an egg.
a spoon cradling some peas.
the candy shell surrounding the chocolate in a piece of M&M candy.
"Sticky ends" are
always long sequences of a single nucleotide.
another name for the 5' cap on mRNA transcripts.
DNA fragments with single-stranded ends.
produced by the action of DNA ligase.
Which of the following explains why DNA from two different sources can be joined together as long as they were cut with the same restriction enzyme?
DNA ligase recognizes that the two sources of DNA were cut with the same enzyme and joins the fragments.
The bases at the sticky ends will be complementary to each other.
The restriction fragments will be the exact same length, which allows the two fragments to join.
The restriction enzyme forms hydrogen bonds with the DNA.
What does the term vector refer to in genetic engineering?
a plasmid or other agent used to transfer DNA into a living cell
the "sticky" ends of a DNA fragment
the enzyme that cuts DNA into restriction fragments
a restriction fragment
Which of the following would be considered a transgenic organism?
a bacterium that has received genes via conjugation
a fern grown in cell culture from a single fern root cell
a human given a corrected human blood-clotting gene
a rat with rabbit hemoglobin genes
A scientist can obtain cDNA from every gene from a particular cell.
True
False
The "sticky ends" that an enzyme creates are called sticky because ___ .
they create two identical single stranded extensions that will base pair.
they create complementary single stranded extensions that will allow two DNA fragments to base pair.
they create a substance that will glue two DNA fragments together
Place the steps to create recombinant DNA in order.
Isolate the gene of interest.
1
2
3
4
Place the steps to create recombinant DNA in order.
Cut the gene of interest and the plasmid vector with the same restriction enzyme to create matching sticky ends.
1
2
3
4
Place the steps to create recombinant DNA in order.
Put the two pieces of DNA into a tube with ligase to seal the cut DNA backbone into a single piece of DNA.
1
2
3
4
A molecule that facilitates the formation of covalent bonds between nucleotides.
DNA ligase
DNA technology
Biotechnology
DNA cloning
Plasmid
A set of techniques for manipulating DNA.
DNA ligase
DNA technology
Biotechnology
DNA cloning
The use of organisms or their products for human purposes.
DNA ligase
DNA technology
Biotechnology
DNA cloning
The creation of a large number of copies of a target sequence of DNA.
DNA ligase
DNA technology
Biotechnology
DNA cloning
A small circular self-replicating DNA molecule separate from the bacterial chromosome used as a vector.
Plasmid
Recombinant DNA
Genetic engineering
Gene therapy
Restriction enzyme
DNA combined from two different sources.
Plasmid
Recombinant DNA
Genetic engineering
Gene therapy
Restriction enzyme
Purposefully altering genes for human purposes
Plasmid
Recombinant DNA
Genetic engineering
Gene therapy
Restriction enzyme
The replacement of a person's disease-causing genes with functioning genes.
Plasmid
Recombinant DNA
Genetic engineering
Gene therapy
Restriction enzyme
An enzyme that "cuts" DNA at specific sequences.
Plasmid
Recombinant DNA
Genetic engineering
Gene therapy
Restriction enzyme
Which of the following statements best describes cancer cells?
Proto-oncogenes control their cell division.
Normal controls over cell division have been altered.
They are more highly differentiated than normal cells.
They will divide 20 to 50 times and then stop.
What is the preferred name of the technique used to determine if DNA comes from a particular individual?
DNA profiling
DNA microarrays
DNA technology
The expression of genes can be turned on or off.
True
False
Proteomics studies _____.
the protein-coding genes encoded in a genome
the mRNA produced by transcribing protein-coding genes
all the proteins encoded in a genome
the proteins involved in genetic diseases
A genetic marker is a _____.
radioactive probe used to find a gene
chart that traces the family history of a genetic trait
place where a restriction enzyme cuts DNA
particular nucleotide sequence whose inheritance can be followed
The study of entire sets of genes and their interactions is referred to as ____ .
biotechnology
genomics
DNA profiling
forensics
A
DNA double helix
Nucleosomes
Tight helical fiber
Looped domain
Duplicated Metaphase
B
DNA double helix
Nucleosomes
Tight helical fiber
Looped domain
Duplicated Metaphase
C
DNA double helix
Nucleosomes
Tight helical fiber
Looped domain
Duplicated Metaphase
D
DNA double helix
Nucleosomes
Tight helical fiber
Looped domain
Duplicated Metaphase
E
DNA double helix
Nucleosomes
Tight helical fiber
Looped domain
Duplicated Metaphase
A normal gene that, if mutated, can lead to cancer.
proto-oncogene
oncogene
tumor-suppressor gene
A gene that causes a cell to become cancerous.
proto-oncogene
oncogene
tumor-suppressor gene
A gene that encodes proteins that inhibit cell division. Such proteins normally help prevent cells from becoming cancerous.
proto-oncogene
oncogene
tumor-suppressor gene
Which of the following statements best describes cancer cells?
Proto-oncogenes control their cell division.
They will divide 20 to 50 times and then stop.
Normal controls over cell division have been altered.
They are more highly differentiated than normal cells.
Which of the following is a use of DNA technology?
Develop vaccines
Produce drugs for therapy
All of these are uses of DNA technology
Pinpoint the microorganisms responsible for outbreaks of disease.
What is the function of the polymerase chain reaction (PCR)?
It can isolate particular genes of interest.
It can identify genetic markers for diseases.
It can make a large of number of copies of isolated DNA.
It can establish paternity.
Put the following five levels of DNA organization in order from least organized to most organized.
Duplicated chromosome
Looped domain
Tight helical fiber
DNA
Nucleosome
(a)
After DNA fragments with matching sticky ends are temporarily joined by complementary base pairing, the union can be made permanent by the "pasting" enzyme
DNA ligase
DNA polymerase
DNA helicase
ATP methylase
Gel electrophoresis is normally set up with the negative electrode at the top of the gel and the positive electrode at the bottom of the gel. The DNA products are loaded at the top of the gel, and then a current is applied to separate them. However, when preparing to run a gel, you accidentally switched the locations of the negative and positive electrodes such that the positive electrode is at the top and the negative electrode is at the bottom. You still loaded the DNA products at the top of the gel as normal. What result are you most likely to observe if you apply an electric current to this gel setup?
All DNA molecules will migrate up the gel toward the positive electrode.
All DNA molecules will migrate down the gel toward the negative electrode.
Shorter DNA molecules will move up the gel, and longer DNA molecules will move down the gel.
Longer DNA molecules will move up the gel, and shorter DNA molecules will move down the gel.
In thinking about their role in cell division, oncogenes are like the ________ of a car, while tumor suppressor genes are like the ________ of a car.
gas pedal; brakes
steering wheel; brakes
gas pedal; headlights
brakes; gas pedal
The use of cloning to produce special embryonic stem cells is called
regenerative cloning
transplantational cloning
reproductive cloning
therapeutic cloning
In multicellular organisms, the coordination of cellular activities relies on
cell receptors that detect transcription factors.
the availability of certain "key" nutrients as cells divide.
operons.
cell-to-cell signaling and signal transduction pathways.
Adult stem cells have limited therapeutic potential
because they are fully differentiated.
because they lack a complete set of genes.
due to their excessive numbers in tissues.
because their developmental potential is limited to certain tissues.
When DNA from two sources is combined into one single piece of DNA, it is known as
cloned DNA
recombinant DNA
a vector
a plasmid
The term "gene expression" refers to the
fact that each individual of a species has a unique set of genes.
fact that individuals of the same species have different phenotypes.
process by which genetic information flows from genes to proteins.
flow of information from parent to offspring.
Which of the following statements regarding proteomics is true?
Proteomics is the study of protein interaction within a cell.
Proteomics involves the complete analysis of the prokaryotes.
Proteomics is the systematic study of the full set of proteins encoded by a genome.
Proteomics and genomics allow scientists to study life in an ever-increasing reductive approach.
What is the correct order of structures in a chromosome from smallest to largest?
nucleotide, nucleosome, histone, supercoil, tight helical fiber, chromosome
nucleosome, nucleotide, histone, tight helical fiber, supercoil, chromosome
nucleotide, histone, tight helical fiber, nucleosome, chromosome, supercoil
nucleotide, histone, nucleosome, tight helical fiber, supercoil, chromosome
Both prokaryotic and eukaryotic cells use ________ to turn certain genes on or off.
RNA transcriptase
intron segments
proteins
nucleosome packing
Restriction enzymes
facilitate nucleotide base pairing.
cut DNA at specific sites.
stop transcription and translation.
bind together strands of DNA.
Which of the following statements about genome sequencing is false?
The genomes of nearly 7,000 species have been completely sequenced.
The first eukaryotic organism to have its genome sequenced was yeast.
Most of the genomes that have been sequenced to date are eukaryotes.
The genome of a mouse has been sequenced.
When plasmids are used to produce a desired protein,
the plasmids are inserted into the bacterial chromosome.
the plasmids multiply and produce the protein outside of the bacterium.
the desired gene is inserted into the plasmid, and the plasmid is returned to the bacterium by transformation.
the bacterial genome and plasmid are inserted into the genome of the cell containing the desired gene (often the cell of a plant or animal).
Which of the following permits a single gene to code for more than one polypeptide?
retention of different introns in the final version of the different mRNA strands
alternative RNA splicing
genetic differentiation
addition of different types of caps and tails to the final version of the mRNA strands
A single cell, the zygote, can develop into an entirely new organism with many different specialized cells. Which of the following statements about this process is false?
Additional genetic information for the formation of specialized cells is passed on to the developing embryo via the mother.
The descendant cells specialize by a process known as differentiation.
The zygote contains all of the genetic information required for the development of many different cell types.
Differentiation of the zygote into a multicellular organism results from selective gene expression.
Which of the following statements regarding cancer risk factors is false?
Factors that alter DNA and make cells cancerous are called carcinogens.
Mutagens are usually not carcinogens.
X-rays and ultraviolet radiation are two of the most potent carcinogens.
Eating 20-30 grams of plant fiber daily and reducing the intake of animal fat can reduce your risk of developing colon cancer.
The cloning of Dolly the sheep
demonstrated that the nuclei from differentiated mammalian cells can retain their full genetic potential.
demonstrated that differentiated cells contain only a fraction of their full genetic potential.
demonstrated, for the first time, that eggs are haploid and body cells are diploid.
revealed that cloned mammals most resemble the egg donor.
The coding regions of a gene are called
introns
exons
promoters
enhancers
Certain bacterial strains have traits that allow them to resist the effects of antibiotic drugs. How do the resistance traits arise in a bacterial population, and under what circumstances will the resistance traits be most common?
The resistance traits arise as the immune systems of the bacteria detect and respond to the drugs. Therefore, individual bacteria become more and more resistant if they are exposed to antibiotic drugs.
The resistance traits are developed by bacteria when they detect the drugs in their environment, through mutations that counteract the drugs' effects. Thus, they are most common wherever the drugs are present.
Resistance traits are produced because antibiotic drugs cause mutations in bacterial cells. The resistance traits only occur in the presence of antibiotics.
The resistance traits are produced by chance mutations and are present to varying degrees in most bacterial populations. Resistance traits will be most prevalent, however, in bacteria that are chronically exposed to antibiotic drugs.
Scientists have warned doctors of the danger of their increasing use of antibiotics for treating minor illnesses. They are concerned because __________.
the drugs will be metabolized more quickly by our bodies, decreasing their effectiveness
strains of bacteria that are resistant to these drugs will become more widespread
these drugs should be used to treat viral diseases, but not bacterial illnesses, against which they have no effect
humans will become tolerant to the effects of the drugs
A cat's forelimb and a human's forelimb are examples of
vestigial structures
pseudogenes
strata
homologous structures
Which of the following best describes relative fitness?
The ability to produce healthy offspring
The change in a population's gene pool over generations
The creation of new gene combinations
Individuals migrating into and out of an area
Which of the following can be passed on to offspring from their parents?
Muscles from body building
A tattoo
A deep tan from constant tanning
Blonde hair
The original source of all genetic variation is _____.
meiosis
recombination
natural selection
mutation
Two populations of flowers are separated by a mountain range and would not be capable of interbreeding. This is an example of:
mechanical isolation
behavioral isolation
ecological isolation
geographical isolation
Two populations of organisms belong to the same biological species when they
have anatomical features that make it difficult for organisms from the two populations to mate with one another.
cannot mate with each other because mating occurs at different times.
encounter each other, mate, and produce viable, fertile offspring under natural conditions.
use different types of behaviors or physical features to attract mates.
Structures that evolved from the same structure in a common ancestor are
analogous
homologous
convergent
Which of the following was a key event in the history of life on Earth?
All of these
Appearance of prokaryotic cells
Appearance of eukaryotic cells
Colonization of land
One species of garter snakes live on land and the other mainly in water.
Habitat
Temporal
Behavioral
Mechanical
Gametic
One species of skunk breeds in the fall and one in late winter.
Habitat
Temporal
Behavioral
Mechanical
Gametic
One species of bird performs an elaborate courtship dance while another builds a flashy nest.
Habitat
Temporal
Behavioral
Mechanical
Gametic
Plant flowers differ in shape and are unable to be pollinated by the same insect.
Habitat
Temporal
Behavioral
Mechanical
Gametic
Molecular incompatibility of eggs and sperm
Habitat
Temporal
Behavioral
Mechanical
Gametic
Offspring do not develop fully.
Behavorial
Mechanical
Gametic
Reduced hybrid viability
Reduced hybrid fertility
Offspring are sterile.
Behavioral
Mechanical
Gametic
Reduced hybrid viability
Reduced hybrid fertility
The gradual adaptation of a population to its environment
microevolution
speciation
biological species concept
morphological species concept
The process by which one species eventually evolves into two different species
microevolution
speciation
biological species concept
morphological species concept
Based on the ability of the organisms to produce fertile offspring
microevolution
speciation
biological species concept
morphological species concept
A system based on similar sizes, shapes, and other physical traits, in other words, morphology (form)
microevolution
speciation
biological species concept
morphological species concept
Identifies species based on their specialized role(s) in their respective environments
morphological species concept
ecological species concept
phylogenetic species concept
macroevolution
A small group of organisms that share a common ancestor; in other words, they share a single branch on the evolutionary tree
morphological species concept
ecological species concept
phylogenetic species concept
macroevolution
Evolutionary changes above the species level
morphological species concept
ecological species concept
phylogenetic species concept
macroevolution
Which of the following are ways in which human practices are contributing to the creation of antibiotic-resistant strains of bacteria? (Select all that apply.)
Patients stopping their prescriptions before the prescribed dosage is completed
Overprescription of antibiotics by physicians
Use of antibiotics in cattle by ranchers.
If a population is in Hardy-Weinberg equilibrium and remains in equilibrium, which of the following will be true?
Individuals survive and reproduce equally well regardless of their genotype.
The relative frequencies of three genotypes (AA, Aa, aa) will gradually become stabilized at 1:1:1.
The dominant allele will take over.
The population organisms will evolve.
All known organisms use genetic information to produce protein molecules via the same genetic code. This finding strongly supports the hypothesis that __________.
there's only one possible way to encode information in a macromolecule
the genetic code readily evolves by natural selection
all organisms are descended from one or a few common ancestors
the earliest macromolecules probably arose when lightning struck an oxygen-free atmosphere
The protection of individuals in malaria stricken areas by being heterozygous for sickle-cell hemoglobin would be an example of ___ .
inclusion of alien DNA
heterozygote advantage
speciation
ecological effect
Who developed a theory of evolution almost identical to Darwin's?
Lyell
Lamarck
Wallace
Aristotle
Which of the following represents a postzygotic barrier?
Temporal
Habitat
Reduced hybrid viability
Gametic
Which of the following is the correct presentation of a species name?
Homo erectus
Homo Erectus
homo erectus
Homo erectus
Place the major events in the history of life in order.
1. Origin of prokaryotes
2. Origin of single-celled eukaryotes
3. Colonization of land
4. Origin of multicellular eukaryotes
(a)
The ability of some organisms to leave more offspring than others due to an advantageous trait.
Natural selection
Genetic drift
Gene flow
Stabilizing selection
Chance events can create changes in the frequency of alleles in a population. This can have a profound effect on small populations.
Natural selection
Genetic drift
Gene flow
Stabilizing selection
When individuals move into or out of a population.
Natural selection
Genetic drift
Gene flow
Stabilizing selection
Favors intermediate phenotypes, reduces variation, and maintains an intermediate trait.
Natural selection
Genetic drift
Gene flow
Stabilizing selection
Shifts the population by acting against one of the phenotypes at the extremes.
Directional selection
Disruptive selection
Charles Darwin
Homology
When conditions exist that favor phenotypes at the extremes and not intermediate phenotypes.
Directional selection
Disruptive selection
Charles Darwin
Homology
The famous biologist who is considered the father of evolution.
Directional selection
Disruptive selection
Charles Darwin
Homology
The similarities seen in certain species that result from common ancestry
Directional selection
Disruptive selection
Charles Darwin
Homology
Selective breeding of domesticated plants and animals for desired traits
Homology
Artificial selection
Founder effect
Microevolution
A few individuals create a new gene pool that does not represent the original gene pool
Homology
Artificial selection
Founder effect
Microevolution
Small changes in the relative frequencies of alleles in a population.
Homology
Artificial selection
Founder effect
Microevolution
A group of birds having a beak that enables them to crack open available seeds on an island
Natural selection
Genetic drift
Gene flow
Stabilizing selection
A forest fire wipes out a national forest and creates a bottleneck effect on certain populations.
Natural selection
Genetic drift
Gene flow
Stabilizing selection
Prairie chickens from other states being added to the population of prairie chickens already found in Illinois.
Natural selection
Genetic drift
Gene flow
Stabilizing selection
Human birth weight
Natural selection
Genetic drift
Gene flow
Stabilizing selection
Bacteria exposed to an antibiotic
Gene flow
Stabilizing selection
Directional selection
Disruptive selection
Small and large-billed African black-bellied seedcracker finches
Gene flow
Stabilizing selection
Directional selection
Disruptive selection
Lyell's book Principles of Geology, which Darwin read on board the H.M.S. Beagle, argued in favor of which of the following concepts?
Earth's surface is shaped mainly by occasional catastrophic events.
The processes that shape Earth today are very different from those that were at work in the past.
Earth's surface is shaped by natural forces that act gradually and are still acting.
Meteorite impacts may have been a major cause of periodic mass extinctions.
Who developed a theory of evolution almost identical to Darwin's?
Larmarck
Wallace
Lyell
Aristotle
When a horse and a donkey mate, they produce infertile hybrids called mules. According to the _____ species concept, horses and donkeys are _____.
biological; the same species
ecological; different species
biological; different species
ecological; the same species
Radiometric dating is based on the decay of radioactive isotopes over time.
True
False
Which of the following includes all of the others?
Species
Family
Phylum
Order
Place the taxonomic groups in order from most inclusive 1->2->3->4->5->6->7->8 to least inclusive.
Species
Order
Genius
Class
Family
Phylum
Kingdom
Domain
(a)
What evidence is used to determine the branching sequence of an evolutionary tree?
experiments in artificial selection
anatomical or molecular homologous structures
the genetic code
an overall assessment of general similarities between organisms
A population is
a group of individuals of the same species that live in the same area and interbreed.
all individuals of a species, regardless of location or time period in which they live.
a group of individuals of different species living in the same place at the same time.
a group of individuals of a species plus all of the other species with which they interact.
A population of 1,000 birds exists on a small Pacific island. Some of the birds are yellow, a characteristic determined by a recessive allele. The others are green, a characteristic determined by a dominant allele. A hurricane on the island kills most of the birds from this population. Only 10 remain, and those birds all have yellow feathers. Which of the following statements is true?
Assuming that no new birds come to the island and no mutations occur, future generations of this population will contain both green and yellow birds.
The hurricane has caused a population bottleneck and a loss of genetic diversity.
This situation illustrates the effect of a mutation event.
The 10 remaining birds will mate only with each other, and this will contribute to gene flow in the population.
Which of the following disciplines has found evidence for evolution based on the native distributions (locations) of living species?
molecular biology
comparative anatomy
geographic distribution
paleontology
Darwin found that many of the species on the Galápagos islands
resembled species on the nearest mainland.
resembled species in Europe.
resembled species from Australia.
were identical to South American species.
Which statement best describes the mode of selection depicted in the figure?
stabilizing selection, changing the average color of the population over time
directional selection, favoring the average individual
directional selection, changing the average color of the population over time
disruptive selection, favoring the average individual
The ultimate source of all new alleles is
mutation
chromosomal duplication
genetic drift
natural selection
The sickle-cell allele produces a serious blood disease in homozygotes. Why doesn't natural selection eliminate this allele from all human populations?
Natural selection is a positive force, so it does not eliminate alleles.
In populations where endemic malaria is present, heterozygotes have an important advantage: They are resistant to malaria and therefore are more likely to survive and produce offspring that carry the allele.
Mutations keep bringing the allele back into circulation.
Natural selection occurs very slowly, but elimination of the sickle-cell allele is expected to occur soon.
Some butterflies can ingest toxic chemicals from the milkweed plants they feed on and then can store those chemicals in their body. Because toxins stored in the butterflies are toxic to birds, the birds avoid eating the butterflies. Which of the following is the best explanation for this situation?
Butterflies that stored the chemicals were never eaten by predators, so those butterflies survived.
Butterflies developed a mutation that led them to be able to store the chemical because they needed to avoid being eaten.
Milkweed plants wanted the butterflies to ingest the chemical so they would no longer feed on the plant, but the butterflies fooled the milkweed by storing the toxic chemicals.
Any butterfly allele that allowed milkweed toxin storage would be likely to persist because butterflies that had it were more likely to survive.
Which of the following statements best describes the true nature of natural selection?
Only the strongest survive.
The strong eliminate the weak in the race for survival.
Organisms change by random chance.
Heritable traits that lead to reproductive sucess become more frequent in a population from one generation to the next.
Which of the following would a biologist describe as microevolution?
the formation of new species
the extinction of species
dramatic biological changes, such as the origin of flight, within a taxon
a change in the gene pool of a population from one generation to the next
A group of ants escaped from a picnic basket carried to the top of a mountain and thrived in this area where there were no other ants. Many years later descendants of these ants crawled into a picnic basket on the mountain and traveled back to the valley from which their ancestors had come. Which of these observations would cause you to conclude that the ants on top of the mountain had become a different species from those in the valley?
The mountain ants and valley ants were different colors.
The mountain ants and valley ants were different sizes.
The mountain ants ate different food than the valley ants.
The mountain ants could not mate with the valley ants.
Which of the following options lists major events in the history of life on Earth in the proper order, from earliest to most recent?
first prokaryotes, photosynthesis, colonization of land by plants and fungi, first eukaryotes
first eukaryotes, photosynthesis, colonization of land by plants and fungi, first prokaryotes
first prokaryotes, first eukaryotes, photosynthesis, colonization of land by plants and fungi
first prokaryotes, photosynthesis, first eukaryotes, colonization of land by plants and fungi
The Mesozoic era is often called the age of reptiles. Which of the following also occurred during this era?
the origin of animals in the oceans
the appearance of the first plants on land
the appearance of the first animals (tetrapods and insects) on land
the appearance of the first mammals and flowering plants on land
The earliest discovered fossils are of ________ dating back to ________ years ago.
single-celled eukaryotes; 4.5 billion
prokaryotes; 3.5 billion
algae; 1 billion
fish; 600 million
Scientists believe that a major factor promoting the adaptive radiation of mammals was probably
their development of fur.
the mass extinction of most dinosaurs, an event that opened up new ecological opportunities.
internal fertilization.
the origin and diversification of flowering plants.
Which of the following options lists taxonomic categories in the correct order from most specific to most general?
genus, family, class, order, phylum
genus, family, order, class, phylum
family, genus, order, phylum, class
family, genus, class, order, phylum
The technique called radiometric dating is based on
the steady, clocklike decay of certain radioactive isotopes over time.
the assumption that radioactive isotopes accumulate in fossils at a constant rate.
the formation of radioactive molecules in rocks after they are laid down.
the use of fossils of known age to determine how fast carbon-14 decays.
Mass extinctions
remove many species, but they are usually replaced within a million years or less by an even greater diversity of life.
mainly serve to "weed out" poorly adapted organisms and make room for new, better adapted species.
remove well-adapted species and groups from the Earth, so that it may take millions of years for species diversity to recover.
are caused by human activity and did not occur prior to the expansion of the Earth's human population.
In the three-domain system, the eukaryotes are represented
only within the domain Eukarya.
only within the domain Archaea.
only within the kingdom Protista.
in all three domains.
Greenhouse gases include
carbon dioxide and methane
nitrous oxide and oxygen
nitrogen and oxygen
carbon dioxide and nitrogen
Ecosystems vary in their energy efficiency, but as a general rule, ____ of the energy available at one level is transferred to the next trophic level.
100%
50%
30%
10%
The only input of new chemicals on the earth is from meteorites.
True, therefore chemicals must be recycled.
False, because chemicals flow out of the ecosystem
Which of the following contribute to the earth's biodiversity? (Choose all that apply.)
Species diversity
Ecosystem diversity
Genetic diversity
Overharvesting
Which of the following includes all the others?
Organism
Population
Community
Ecosystem
Certain elements are continuously cycled between biotic and abiotic portions of an ecosystem.
True
False
A scientist that is studying the habitat of mountain gorillas is most accurately called a(n)
ecologist
mountainist
philologist
biologist
Which of the following is a characteristic of a tropical rain forest?
Contains nutrient-poor soil.
Forest structure consists of distinct layers.
All of these are characteristics of tropical rain forests.
Found along the equator.
Which of the following are abiotic factors that influence organisms within their habitat? (Select all that apply.)
Temperature
Sunlight
Water
Removal of a keystone species from a community will
likely reduce species richness.
have no effect at all.
most likely increase species richness.
have an effect only if the species removed is a predator.
A specific region of earth occupied by organisms that is unique in climate and species
Biome
Biosphere
Ecosystem
Community
Population
All regions of the earth occupied by organisms
Biome
Biosphere
Ecosystem
Community
Population
Community and the nonliving factors
Biome
Biosphere
Ecosystem
Community
Population
Groups of multiple species in the same area
Biome
Biosphere
Ecosystem
Community
Population
Group of the same species in an area
Biome
Biosphere
Ecosystem
Community
Population
Contain grasses and some trees (along rivers and streams). In regions of cold winter temperatures. Fires and grazing inhibit tree growth.
Temperate grassland
Temperate forest
Coniferous forest
Tundra
Characterized by a large amount of rainfall to support large trees. Temperatures can vary widely between summer and winter.
Temperate grassland
Temperate forest
Coniferous forest
Tundra
Dominated by coniferous trees and are found at high latitudes. Characterized by long and cold winters followed by short and wet summers.
Temperate grassland
Temperate forest
Coniferous forest
Tundra
Characterized by permafrost and little to no light in autumn and winter, receive little rainfall. Their winters are very cold and windy.
Temperate grassland
Temperate forest
Coniferous forest
Tundra
A terrestrial biome characterized by grasses, few trees, periodic fires, and a brief rainy season
Coniferous forest
Tundra
Savanna
Deserts
Characterized by little rainfall and sparse populations
Coniferous forest
Tundra
Savanna
Deserts
Which of the following converts inorganic components of the ecosystem into organic substances?
Producers
None of the above
Decomposers
Consumers
Which of the following explains why nitrate-heavy fertilizers are problematic?
Bacteria convert it to N2.
Bacteria convert it to NH3.
It is easily washed out by rain or irrigation.
It combines with oxygen in the soil, which increases the soil acidity.
What happens to the amount of stored energy as organic material is transferred up the food chain?
It stays the same.
It decreases greatly.
It decreases slightly
It increases.
There is a constant input of energy from the ___ .
Primary producers
Primary consumers
Sun
A
Secondary & Tertiary consumer
Primary consumer
Producers
Decomposers and Detritivores
B
Secondary & Tertiary consumer
Primary consumer
Producers
Decomposers and Detritivores
C
Secondary & Tertiary consumer
Primary consumer
Producers
Decomposers and Detritivores
D
Secondary & Tertiary consumer
Primary consumer
Producers
Decomposers and Detritivores
Every food chain must begin with a
group of producers.
collection of primary consumers.
quaternary consumer.
group of decomposers.
Which of the following type of interspecific interaction benefits both organisms?
Parasitism
Mutualism
Predation
Herbivory
Which of the following statements about temperate broadleaf forests is true?
Temperate broadleaf forests have a narrow range of temperatures over the course of a year.
Oak, hickory, birch, beech, and maple are common trees in temperate broadleaf forests.
Temperate broadleaf forests have very poor soil.
Temperate broadleaf forests are less open than tropical rain forests.
Which of the following correctly pairs a biome and its characteristics?
temperate broadleaf forest-- mild winters; scarce rainfall; predominantly dicot vegetation
chaparral-- mild, rainy winters; long, hot, but wet summers
savanna-- long, cold winters; vegetation dominated by conifers
tundra-- very cold winters; only the upper layer of the soil thaws during summer
All of Earth that is inhabited by life is called the
atmosphere
ecosystem
biosphere
biome
The dominant herbivores in savannas are
gophers
insects
antelope
giraffes
The level of ecologic organization that incorporates abiotic factors is the
community
ecosystem
population
species
While on a walk through a forest, you notice birds in trees, earthworms in the soil, and fungi on plant litter on the forest floor. Based on your observations, you conclude that each of these organisms occupies a different
habitat
ecosystem
biosphere
biome
Factors that help to perpetuate temperate grasslands, such as the American prairies, and prevent them from becoming woodlands include
poor soil
periodic drought and fires
large numbers of cacti
mild winters with very little rain
A keystone species that is a predator will
maintain the species diversity in a community.
harvest prey species down to extinction.
help many of its prey reproduce.
reduce the diversity of the community.
Camouflage typically evolves as a result of
predation
interspecific competition
mutualism
herbivory
The prokaryotes that cause tooth decay have a ________ relationship with humans.
parasitic
predatory
mutualistic
competitive
Which trophic level in this food chain represents the secondary consumer?
trophic level A
trophic level B
trophic level C
trophic level D
A community is composed of
potentially interacting populations of different kinds of organisms.
one species of organism living in a specific environment on Earth.
living organisms and their nonliving environment.
the factors that constitute an organism's niche.
Which arrow shows CO2 released as a product of cellular respiration?
arrow A
arrow B
arrow C
arrow D
In a hypothetical food chain consisting of grass, grasshoppers, sparrows, and hawks, the grasshoppers are
primary consumers
primary producers
secondary consumers
secondary producers
Organisms that digest molecules in organic material and convert them into inorganic forms are
primary consumers
decomposers
primary producers
detritivores
The flow of ________ into ecosystems occurs in one direction only, while ________ are recycled within the ecosystem itself.
minerals; energy compounds
genetic information; genotypes
organic compounds; minerals
energy; chemicals
CO2 in the atmosphere is absorbed by ________ and converted into biomass.
the ozone layer
other atmosphere gases
photosynthetic organisms
large land masses
Biodiversity considers
the genetic diversity within and between populations of a species.
the fate of water in the ecosystem.
commensal relationships between species.
the relationships of individuals to a food chain.
Currently, the single greatest threat to biodiversity is
global warming.
habitat destruction due to humans.
the introduction of exotic species.
overexploitation of populations for food.
