Deck 12: Chromosomal Rearrangements and Changes in Chromosome Number

Question 1

The mass extinction that led to the dinosaurs' demise around 65 million years ago is thought by many to be the result of a large asteroid impact near present day

A) Iceland.
B) Hawaii.
C) Siberia.
D) Manitoba.
E) Yucatan.

Answer 1

E

Question 2

Entirely new genes may arise from the process of

A) gene conversion.
B) exon shuffling.
C) genetic drift.
D) concerted evolution.
E) transposition.

Answer 2

B

Question 3

The β-globin gene superfamily has three major components located on three separate chromosomes in humans.They are the β-globin gene family,the ______________________ gene family,and the myoglobin gene.

A) α-globin
B) Hba-ps4
C) gamma globulin
D) delta globin
E) leghemoglobin

Answer 3

A

Question 4

Telomeric repeated DNA sequences contain a hexomeric repeating unit containing a _______________ sequence motif.

A) TTAGGG
B) GGGAAA
C) TTTAGG
D) TTTGGG
E) TGATGC

Question 5

A diagram depicting the evolutionary history of a gene is called a

A) node.
B) branch diagram.
C) phylogenetic tree.
D) molecular clock.
E) pedigree.

Question 6

Strong positive selection often leads to fixation.

Question 7

A protein that appears to have a constant rate of change over a number of lineages,such as cytochrome C in mammals,can be useful as a

A) transcription factor.
B) transposon.
C) phylogenetic tree.
D) molecular clock.
E) polymorphism.

Question 8

LINE,SINE,and retroviral DNA sequences are sometimes termed

A) "selfish" DNA.
B) selectively neutral.
C) middle repetitive-DNA sequences.
D) unique-sequence DNA.
E) "useless" DNA.

Question 9

Which of the following is not a way changes affecting evolution occur in the regulatory gene network for heart development that is conserved from Drosophila to mammals?

A) substitution of transcription factor families in the network
B) mutations in the cis-element that change its binding affinity
C) mutation in cis-elements that allow it to bind to different transcription factors
D) repositioning of cis-elements
E) insertion or deletion of cis-elements

Question 10

Tandem repeat loci are more susceptible to unequal cross-over than non-repetitive DNA.

Question 11

What defines a network motif?

A) a pattern of interactions that occurs at a higher than random frequency
B) a conserved protein domain that occurs throughout a gene family
C) a conserved cis-regulatory domain that occurs throughout a gene family
D) an enzyme that is part of a branched metabolic pathway
E) a co-factor that is part of a linear metabolic pathway

Question 12

Human heterozygotes for sickle cell anemia are selectively more fit than the normal homozygotes and considerably more fit than individuals homozygous for the sickle cell allele.This enhanced fitness of the heterozygotes is known as

A) adaptive value.
B) reproductive fitness.
C) heterozygous advantage.
D) hybrid vigor.
E) genetic drift.

Question 13

SINE elements are evolutionarily related to

A) cDNA sequences.
B) tRNA sequences.
C) snRNP RNA species.
D) rRNA.
E) mRNA.

Question 14

Hox proteins have in common the functional capacity to

A) transcribe target genes.
B) reduce gene expression in developmental genes.
C) act as DNA-binding transcription factors.
D) transpose as a group.
E) function as epistatic regulators of 3' Hox genes.

Question 15

Selection may act even on synonymous mutations.

Question 16

Nucleotide or amino acid substitutions that have no apparent effect on an organism's phenotype,function,or development are considered _______________________ mutations.

A) neutral
B) conservative
C) advantageous
D) non-coding
E) reverse

Question 17

Which of these accumulates mutations at the slowest rate?

A) an intron
B) a pseudogene
C) a LINE
D) β-globin coding region
E) a SINE

Question 18

Homologous LINE and SINE elements in close proximity on the same chromosome can increase the rate of

A) unequal crossing over.
B) duplications.
C) mutations.
D) deletions.
E) both unequal crossing over and duplications.

Question 19

The genomes of humans and chimpanzees are 99 percent similar;however,many evolutionary biologists believe that most of the phenotypic differences between the two species involve

A) whole genome duplication and polyploidization
B) changes in DNA regulatory and developmental protein factors
C) appearance of thousands of novel proteins
D) changes primarily in coding regions
E) new metabolic pathways

Question 20

Branch length in a phylogenetic tree is proportionate to

A) the number of populations analyzed
B) the number of genes analyzed
C) the number of individual analyzed
D) the number of taxa analyzed
E) the number of molecular changes that have occurred

Question 21

Phylogenetic trees have nodes and branches;branches represent taxonomic units while nodes represent the relationship of these units.

Question 22

Species-specific differences in phenotype are most likely due to differences in gene expression rather than mutations within genes.

Question 23

Catastrophic evolution has occurred a number of times during the Earth's history and has resulted in drastic changes in species numbers and dominance.If a large asteroid struck the earth today,what would be the effects of an oceanic impact and what might be the consequences?

Question 24

A single ancient oxygen-binding molecule is ancestral to modern haemoglobins and myoglobin.

Question 25

Scientists have determined that chimpanzee and human genomes are approximately 99 percent similar with nearly identical karyotypes,yet remarkable differences exist in phenotypic expression.Interpret this data.

Question 26

Humans evolved from chimpanzees about 6 billion years ago.

Question 27

Based on DNA genotyping,Neanderthals were determined not to be direct ancestors of modern man.

Question 28

Duplications increase genome size and occur through transposition and unequal crossing-over.

Question 29

Metazoans are multicellular animals.

Question 30

Two hypothetical populations of animals exist: one is immense,covering a large continent,and the other rather small,which occupies an area the size of Chicago,IL.Predict the effect of each population's size on its genetic drift.

Question 31

Androgen receptor genes in humans and primates contain an enhancer not found in the mouse version of the same gene.

Question 32

What are three features of the Burgess Shale fossils?

Question 33

In evolutionary terms,what is punctuated equilibrium?

Question 34

Concerted evolution allows changes in single genetic elements to spread across a complete set of genes in a gene family.

Question 35

Gene conversion outcome of unequal crossing-over allows the transfer of information from one gene to another.

Question 36

Punctuated equilibrium of evolution is the tendency of evolution to proceed through long periods of stasis followed by short explosive periods of change.

Question 37

How could you calculate the rate of evolution used in a molecular clock?