Question 1

The Lamiaceae is a ________ of _______.
A) order; plants
B) order; animals
C) genus; animals
D) family; plants
E) family; animals

Accepted Answer

Lamiaceae is a family of plants, specifically known as the mint family. Therefore, the correct answer is D - family; plants.

Question 2

Which statement about biological classification is false?
A) Taxonomists use biological classification to show evolutionary relationships among organisms.
B) Separate rules for classification were established by botanists and zoologists.
C) The same binomial name may be given to two different organisms as long as they are in different phyla.
D) Classifications should be monophyletic.
E) A monophyletic group may be removed from a phylogenetic tree by "cutting" a single branch.

Accepted Answer

The same binomial name cannot be given to two different organisms as it is the unique identifier for an individual species. This statement is false and violates the principles of biological nomenclature.

Question 3

Scientists have been able to reconstruct DNA sequences in an ancestral archosaur to produce an opsin protein.Knowledge of the opsin sequence in the ancestral archosaur provides clues about the animals' visual capabilities and probable behaviors.Which is conclusion based on their results is false?
A) The ancient archosaur was probably nocturnal.
B) The ancestral state for this protein could not be recreated.
C) Phylogenetic analysis allowed scientists to reconstruct the change(s) in opsin.
D) The opsin protein of the archosaur was shifted to the red end of the spectrum.
E) Phylogenetic analyses can be used to reconstruct extinct species.

Accepted Answer

The statement that the ancestral state for this protein could not be recreated is false because the scientists were able to reconstruct DNA sequences to produce an opsin protein, indicating they could recreate the ancestral state of the protein.

Question 4

Humans and chimpanzees diverged about 6 million years ago.If 20 nucleotide substitutions have occurred between human and chimpanzee lineages in a sequence of mitochondrial DNA, and 30 have occurred between humans and gorillas, then, according to the molecular clock hypothesis, humans and gorillas separated _______ million years ago.
A) 3
B) 6
C) 9
D) 12
E) 30

Accepted Answer

The molecular clock hypothesis assumes a constant rate of nucleotide substitution over time. If we know the number of substitutions between two species, we can estimate the time since their last common ancestor by dividing the number of differences by the rate of substitution per unit time. Using this method, if 20 nucleotide substitutions have occurred between humans and chimpanzees, and 30 have occurred between humans and gorillas, we can calculate the rate of substitution as (20+30)/2=25 substitutions per 6 million years. Therefore, the number of substitutions expected between humans and gorillas will be 25*(time since their separation). Solving for time, we get time=30/25=1.2 million years since their separation. Therefore, humans and gorillas separated 6+1.2=7.2 million years ago.

Question 5

Which statement about molecular clocks is true?
A) They can give an average rate of change in an amino acid sequence.
B) They can only be used to date very ancient events.
C) When different proteins are compared, the slope of the plotted line representing the average rate of divergence is the same for all proteins.
D) They do not show the timing of splits between lineages.
E) They cannot predict the order in which evolutionary lineages diverged.

Accepted Answer

Molecular clocks can give an average rate of change in an amino acid sequence, which can be used to estimate when different organisms diverged from a common ancestor.

Question 6

Males of a species of sparrow sing very rapid songs.Experimental evidence shows that females of this species prefer these fast songs over slowed-down songs.Which would be the strongest support for the sensory exploitation hypothesis?
A) Related species have males that also sing very fast, and females also prefer these fast songs.
B) Related species have males that also sing very fast, but females prefer males with slower songs.
C) Related species have males that do not sing as fast, but the females from these other species also prefer very fast songs over songs of males from their own species.
D) Related species have males that do not sing as fast, and females from these species prefer the song speeds of males of their own species.
E) Females of related species are indifferent to the speed of the males' songs.

Accepted Answer

The sensory exploitation hypothesis suggests that a male's trait exploits a pre-existing sensory bias in females. Choice C provides support for this hypothesis by showing that females from other species that do not have males that sing as fast still prefer the fast songs over the songs of males from their own species, indicating a pre-existing sensory bias for fast songs.

Quiz 21: Reconstructing and Using Phylogenies

The Lamiaceae is a __ of _.

Which statement about biological classification is false?

Scientists have been able to reconstruct DNA sequences in an ancestral archosaur to produce an opsin protein.Knowledge of the opsin sequence in the ancestral archosaur provides clues about the animals' visual capabilities and probable behaviors.Which is conclusion based on their results is false?

Which statement about molecular clocks is true?

Males of a species of sparrow sing very rapid songs.Experimental evidence shows that females of this species prefer these fast songs over slowed-down songs.Which would be the strongest support for the sensory exploitation hypothesis?