Question 1

Only 61 of the 64 codons specify an amino acid.What do the other three codons encode?

Accepted Answer

The answer of Only 61 of the 64 codons specify...

Question 2

Which concept describes the idea that the most closely related molecular sequences are those with the smallest number of differences between them?

Accepted Answer

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

Question 3

Theodosius Dobzhansky and Ernst Mayr drew on ideas from Darwin,Fisher,Wright,Haldane,and others to demonstrate how evolution operates in real populations.These observations lead to which evolutionary genetics theory?

Accepted Answer

The answer of Theodosius Dobzhansky and Ernst Mayr drew on...

Question 4

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)?

Accepted Answer

The answer of In eukaryotes,most of the cells' DNA is...

Question 5

In double-stranded DNA,the percentages of adenine and thymine are approximately equal to each other,as are the percentages of cytosine and guanine.This relationship is better known as what (named for the person who made this discovery)?

Accepted Answer

The answer of In double-stranded DNA,the percentages of adenine and...

Question 6

There are 64 codons and 20 amino acids,meaning that the genetic code is ________.

Accepted Answer

The answer of There are 64 codons and 20 amino...

Question 7

Organisms are constantly evolving and phylogenetic relationships can be reevaluated.Refer to the phylogenetic tree to answer the following questions.
 
-What feature distinguishes snakes and mammals from frogs and salamanders?

Accepted Answer

The answer of Organisms are constantly evolving and phylogenetic relationships...

Question 8

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

Accepted Answer

The answer of The work of Walter Sutton and Theodor...

Question 9

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

Accepted Answer

The answer of With the assistance of William Bateson,Archibald Garrod...

Question 10

What are the three principal components of a DNA nucleotide?

Accepted Answer

The answer of What are the three principal components of...

Question 11

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?

Accepted Answer

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

Question 12

The promoter is bound by the transcription factors and which enzyme?

Accepted Answer

A) DNA polymerase 
B) RNA polymerase 
C) reverse transcriptase 
D) DNase 
E) RNase

Question 13

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?

Accepted Answer

The answer of The physical units of heredity composed of...

Question 14

DNA strands can be pulled apart by adding heat and "melting" the double-stranded DNA.The temperature required to melt a region of DNA changes based on the base-pair composition.Based on the structure of the A-T and C-G bonds in Figure 1.11,which bonds would require more energy (heat)to break them? How might this help you predict which regions of the DNA helix may be the most stable and harder to break apart? (This can be used to predict regions that are not transcribed as often,as you'll see in later chapters.)

Accepted Answer

The answer of DNA strands can be pulled apart by...

Question 15

Bacteria are single-celled organisms with a single chromosome found in which cell space?

Accepted Answer

A) nucleus 
B) nucleolus 
C) nucleoid 
D) nuclear envelope 
E) mitochondria

Question 16

In retroviruses,DNA is synthesized from an RNA template using which enzyme?

Accepted Answer

The answer of In retroviruses,DNA is synthesized from an RNA...

Question 17

Which type(s)of RNA is/are translated into proteins?

Accepted Answer

A) mRNA 
B) rRNA 
C) tRNA 
D) mRNA and rRNA 
E) mRNA,rRNA,and tRNA

Question 18

After replication,chromosomes consist of how many molecules of DNA (assuming one chromatid is equal to one molecule of DNA)?

Accepted Answer

The answer of After replication,chromosomes consist of how many molecules...

Question 19

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?

Accepted Answer

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

Question 20

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

Accepted Answer

The answer of The ________,first proposed by Francis Crick,summarizes the...

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