Deck 1: The Molecular Basis of Heredity, Variation, and Evolution

Question 1

Only sixty- one of the sixty- four codons specify an amino acid. In what process do the other three codons function?

A) termination of transcription
B) initiation of replication
C) termination of translation
D) initiation of transcription
E) initiation of translation

Answer 1

C

Question 2

Identify which of the following includes three possible components of a RNA nucleotide?

A) deoxyribose, uracil, phosphate group
B) deoxyribose, cytosine, phosphate group
C) deoxyribose, guanine, phosphate group
D) ribose, thymine, phosphate group
E) ribose, adenine, phosphate group

Answer 2

E

Question 3

What is the sequence and polarity of the DNA strand complementary to the strand 5' AAATGTCCATGC 3'?

A) 5' UUUACAGGUACG 3'
B) 3' UUUACAGGUACG 5'
C) 3' AAATGTCCATGC 5'
D) 5' TTTACAGGTACG 3'
E) 3' TTTACAGGTACG 5'

Answer 3

E

Question 4

What kind of bond is formed between complementary base pairs to join the two DNA strands into a double helix?

A) hydrogen bond
B) peptide bond
C) ionic bond
D) disulfide bond
E) phosphodiester bond

Question 5

Retroviruses carry their genetic information in the form of RNA, which is subsequently coded into DNA after the virus enters its host cell. What enzyme does the retrovirus use to produce this initial DNA?

A) RNA polymerase
B) ribosomes
C) reverse transcriptase
D) DNA polymerase
E) reverse translationase

Question 6

What kind of bond is formed between the 5' phosphate group of one nucleotide and the 3' hydroxyl (OH) group of the adjacent nucleotide?

A) hydrogen bond
B) disulfide bond
C) hydroxyl bond
D) ionic bond
E) phosphodiester bond

Question 7

The movement of DNA or RNA in gel electrophoresis is often a matter of molecular weight alone. Which of the following molecular parameters usually influence the movement of protein?

A) only shape
B) only charge
C) weight, charge, or shape
D) only weight
E) only weight and shape

Question 8

Messenger RNA (mRNA) is .

A) the molecule that carries the genetic information from DNA and is used as a template for protein synthesis
B) the major structural material making up ribosomes
C) the monomer of polypeptides
D) a molecule that incorporates a specific amino acid into the growing protein when it recognizes a specific group of three bases
E) the major structural component of chromosomes

Question 9

If a eukaryotic chromosome was composed of 20% adenine, how much cytosine should theoretically be present in that same chromosome?

A) 40%
B) 30%
C) 60%
D) 10%
E) 20%

Question 10

Modern genetics consists of three major branches. Which of these branches, also known as "transmission genetics," involves the study of the transmission of traits and characteristics in successive generations?

A) molecular
B) evolutionary
C) reproductive
D) Mendelian
E) population

Question 11

What chemical group appears on the 5' carbon of a DNA nucleotide?

A) carboxyl group
B) phosphate group
C) nitrogenous base
D) hydroxyl group
E) amino group

Question 12

Sexual reproduction uses to generate gametes, which join at fertilization.

A) mitosis; diploid
B) meiosis; haploid
C) mitosis; identical
D) meiosis; diploid
E) mitosis; haploid

Question 13

You identify a new unicellular organism with multiple chromosomes organized by proteins within the cell's nucleus. Into which of the three domains of life might this organism fit?

A) Eukarya
B) Archaea
C) Bacteria
D) Archaea or Bacteria
E) Archaea or Eukarya

Question 14

What kind of bond is formed between successive amino acids during translation?

A) ionic bond
B) phosphodiester bond
C) peptide bond
D) hydrogen bond
E) disulfide bond

Question 15

Watson and Crick used evidence from several studies to determine the structure of DNA. What conclusion were they able to draw from Rosalind Franklin's X- ray diffraction data, specifically?

A) DNA nucleotides form complementary base pairs.
B) The DNA strands are antiparallel, and the strands are held together by hydrogen bonds.
C) DNA consists of four types of nucleotide bases: A, T, C, and G.
D) DNA is a duplex, with two strands forming a double helix.
E) Adenine pairs with thymine and cytosine pairs with guanine when they are on opposite DNA strands.

Question 16

What is the process of synthesizing single- stranded RNA from template DNA?

A) transduction
B) replication
C) transformation
D) translation
E) transcription

Question 17

What is the process of synthesizing proteins from mRNA sequences?

A) transcription
B) replication
C) transformation
D) transduction
E) translation

Question 18

When a diploid cell divides by mitosis, the result is .

A) identical diploid cells
B) identical haploid cells
C) unique haploid cells
D) a zygote
E) unique diploid cells

Question 19

Use the data in the following table to determine which nucleic acid sample can be ALL of the following 4 types: double- stranded DNA, single- stranded DNA, double- stranded RNA, or single- stranded RNA. $$\begin{array} { | l l| } \hline \text { Nucleic Acid Sample } & \text { Data } \\\text { Sample } 1 & 25 \% \text { of the bases are thymine } \\\text { Sample } 2 & 35 \% \text { of the bases are adenine } \\\text { Sample } 3 & 25 \% \text { of the bases are uracil } \\\text { Sample } 4 & 55 \% \text { of the bases are cytosine } \\\text { Sample } 5 & 50 \% \text { of the five- carbon sugars are } \\& \text { deoxyribose }\\\hline\end{array}$$

A) Sample 1
B) Sample 2
C) Sample 3
D) Sample 4
E) Sample 5

Question 20

What are the DNA regulatory sequences recognized by RNA polymerase called?

A) anticodons
B) termination sequences
C) promoters
D) introns
E) proteomes

Question 21

Which of the follow refers to all the RNA produced by transcription of DNA?

A) population genetics
B) proteome
C) transcriptome
D) translatome
E) genome

Question 22

With the assistance of William Bateson, Archibald Garrod produced the first documented example of a human hereditary disorder that shaped the study of biochemical pathways. Which disorder were they describing?

Question 23

Messenger RNA codons pair with tRNA anticodons at which cell structure?

Question 24

The physical units of heredity composed of defined DNA sequences that collectively control gene transcription and contain the information to produce RNA molecules or proteins are better known as what?

Question 25

In eukaryotes, most of the cells' DNA is found in the form of chromosomes in the nucleus. Which organelles contain their own genomes (descended from ancient endosymbiotic bacteria)?

Question 26

Which evolutionary process describes the movement of members of a species from one population to another?

A) natural selection
B) migration
C) mutation
D) random genetic drift
E) population genetics

Question 27

In the phylogenetic tree below, which feature distinguishes snakes and mammals from frogs and salamanders?

A) legs
B) head
C) milk
D) notochord
E) amniotic egg

Question 28

Which evolutionary process involves the slow addition of allelic variation that increases the hereditary diversity of populations, ultimately leading to evolutionary change?

A) natural selection
B) migration
C) mutation
D) random genetic drift
E) population genetics

Question 29

Which evolutionary process relies on the premise that individuals with the best adaptations are most successful at reproducing and leave more offspring than those with less adaptive forms?

A) natural selection
B) migration
C) mutation
D) random genetic drift
E) population genetics

Question 30

What are the three domains of life?

Question 31

A complete set of chromosomes is transmitted to produce identical daughter cells in which cell division process?

Question 32

The genotypes of humans are more than 99% similar. What is the term that describes the alternative forms of genes that contribute to human genetic variation?

Question 33

Which evolutionary process is most pronounced in small populations where statistical fluctuations in allele frequencies can be significant from one generation to the next?

A) natural selection
B) migration
C) mutation
D) random genetic drift
E) population genetics

Question 34

Hereditary anemia known as sickle cell disease (SCD) results from inheritance of a variant form of fi- globin protein (fiS), rather than the wild- type fi- globin protein (fiA). Which of the following did Linus Pauling find following gel electrophoresis of hemoglobin protein from individuals with the following three genotypes: fiAfiA, fiAfiS, or fiSfiS?

A) all three lanes had just one protein band with the same electrophoretic mobility
B) the lane containing the hemoglobin from the heterozygote (fiAfiS) individual had two protein bands with differing electrophoretic mobility
C) the lane containing the hemoglobin from the homozygous (fiAfiA) individual had two protein bands with differing electrophoretic mobility
D) the lane containing the hemoglobin from the homozygous (fiSfiS) individual with SCD had two protein bands
E) all three lanes had the same two protein bands with the same electrophoretic mobility

Question 35

Morphological or molecular characters shared by members of a clade are called .

A) common ancestors
B) paraphyletic groups
C) monophyletic groups
D) synaptomorphies
E) homoplasmies

Question 36

You have digested a molecule of DNA and want to identify a specific fragment of interest. The DNA is subjected to gel electrophoresis, but you get two bands that are very close in size. What could you use to determine which band is the correct one?

A) southern blot
B) western blot
C) northern blot
D) eastern blot
E) stain with ethidium bromide

Question 37

During DNA replication, nascent DNA strands are synthesized in only one direction. Nucleotides are added only to which end of the nascent strand?

Question 38

Which of the following statements is NOT consistent with the DNA fragments shown in the gel?

A) Band 1 is closer to the origin of migration than Band 2
B) Band 1 must have been stained or hybridized by a molecular probe
C) Band 1 has a lower molecular mass than Band 2
D) Band 1 has a lower electrophoretic mobility than Band 2
E) Band 1 must have a negative charge

Question 39

Which term describes a set of organisms that descended from a single common ancestor and are more closely related to other members of the group than to organisms outside the group?

A) species
B) paraphyletic group
C) monophyletic group
D) parsimony
E) phylogeny

Question 40

Hereditary anemia known as sickle cell disease (SCD) results from inheritance of a variant form of fi- globin protein (fiS), rather than the wild- type fi- globin protein (fiA). The fiS protein does not migrate as far as the fiA protein. Which of following does NOT explain why the gel electrophoresis lane containing the hemoglobin protein from the heterozygous (fiAfiS) individual has two protein bands?

A) The protein bands migrated different distances based solely on differences in molecular weight.
B) The different electrophoretic mobility of the two proteins was a result of differences in their molecular weight, charge, and/ or shape.
C) The band closer to the origin of migration contained fiS protein and the band farther from the origin of migration contained fiA protein.
D) The fiS protein has a lower electrophoretic mobility.
E) The fiA protein has a higher electrophoretic mobility.

Question 41

Describe the evolutionary relationship of lancelets to tunicates and to hagfishes. Are lancelets more closely related to tunicates or to hagfishes, or are they equally related?

Question 42

Peptidyl transferase and other proteins power the continuous progression of the ribosome along mRNA and catalyze what type of bond formation in the growing polypeptide chain?

Question 43

Based on molecular evidence, the ancestor of snakes had legs. How might you explain the loss of legs in modern snakes?

Question 44

What are the three major types of RNA and their functions? What would happen to translation if each type of RNA were degraded?

Question 45

Describe what is meant by adaptive and nonadaptive evolution. Which type of evolution might be represented by the differences in the shape of finch beaks on different islands with different food sources, and which type by the presence of both attached and detached earlobes in a given population?

Question 46

Both sugar gliders and flying squirrels have evolved characteristics that allow them to glide, despite being geographically separated. Similar traits that have independent origins arise as a result of what phenomenon?

Question 47

What process proposed by Wallace and Darwin describes the higher rates of survival and reproduction of certain forms of a species over alternative forms?

Question 48

You obtain the following sequence data from a group of related populations: Construct a phylogenetic tree that fits the data and requires the least amount of genetic change, in other words, t most parsimonious outcome. Indicate which genetic changes occurred, if any, that were passed down to descendant populations.

Question 49

DNA replication is called because the newly replicated DNA consists of a parental strand (from the original DNA) and a newly synthesized daughter strand.

Question 50

The , first proposed by Francis Crick, summarizes the relationships between DNA, RNA, and protein.

Question 51

DNA strands can be pulled apart by adding heat and "melting" the double- stranded DNA. The temperature required that melts a region of DNA changes based on the base- pair composition. Based on the structure of the A- T and C- G bonds in the accompanying figure, which type of bond would require more energy (heat) to break? How might this help you predict which regions of the DNA helix may be the most stable and harder to break apart?

Question 52

The work of Walter Sutton and Theodor Boveri suggested that the hereditary units, or
genes, described by Mendel are located on .

Question 53

A general labeling compound called _ attaches to all DNA or RNA in a gel by binding to the sugar- phosphate backbone, thus allowing researchers to visualize the nucleic acids when the gel is exposed to UV light.

Question 54

As natural selection increases the frequency of one morphological form over another in the population, what changes at the genotypic level?

Question 55

Before transferring DNA from a gel to the membrane in Southern blotting, the DNA must be denatured (usually by soaking the gel in NaOH). Why is this step necessary?

Question 56

What type of diagram would you use to depict morphological or molecular similarities and differences that identify evolutionary relationships?

Question 57

Phylogenetic trees are constructed based on morphological characteristics, but molecular phylogenetic trees are constructed based on which feature?

Question 58

Genetic experiments have revealed the relationship between the observable traits of an organism, or _ _, and the genetic constitution of an organism, or .

Question 59

The DNA sequence below encodes the first five amino acids of a large protein. 5' ATGTTAGGATATCAG 3'
3' TACAATCCTATAGTC 5'
a. Identify the coding and template strands.
b. Write the sequence and polarity of the mRNA transcript produced by this sequence. Which process in the ce dogma of biology did you perform? Where does this process occur in eukaryotes?
c. Write the amino acid sequence of the amino acids produced using the three- letter code for amino acids. (See genetic code table in text.) Which process in the central dogma of biology did you perform? Where does this process occur in eukaryotes?