370 Exam 1 QotWeek 3

If one human protein contains 400 amino acids, how many nucleotides need to be in the exons of the corresponding gene to properly code for it?

1200

The fruit fly (Drosophila melanogaster) has four pairs of chromosomes. How many chromosomes would you find in an unfertilized egg (female gamete or sex cell) of this species?

4

An addition or deletion of one or two base pairs in a gene sequence results in a __________ mutation.

frameshift

Sometimes the relationships between taxa remain unresolved due to missing or conflicting data. For example, a node in the phylogeny of mammals might have three branches arising from it, leaving the evolutionary history of the placentals, marsupials, and monotremes uncertain. These nodes are represented on a phylogeny by a __________.

polytomy

The purple flower of the F1 offspring of Gregor Mendel's parental generation crosses indicated that __________.

purple color in flowers is dominant to white color

All of the following differ between phylogenies and pedigrees, except__________.

that they represent patterns of ancestry over time

A type of mutation in which a region of one chromosome is moved to a different chromosome is called __________.

translocation

The figure shows a phylogeny of snakes and their relatives. Based on the information in this figure about which taxa are known to be venomous, why did Bryan Fry and his colleagues hypothesize that monitor lizards and iguanas would also be venomous?

If venomousness is homologous in snakes and Gila monsters, then others in the monophyletic group that includes these species also may have inherited this trait from their common ancestor.

Which of Gregor Mendel's laws contradicts the blending theory of inheritance?

Mendel's first law, the law of segregation

In the 1850s and 1860s, Gregor Mendel bred pea plants and examined the way that traits were passed down across generations. His conclusions, although not accepted during his lifetime, established the foundation for the field of genetics. Of the choices listed, what is the most relevant summary of Mendel's conclusions?

The hereditary factors responsible for traits such as seed shape and flower color are inherited as discrete units.

Do the phylogenies in the figure show the same or different relationships between taxa 1 through 4?

They show the same relationships because rotating the nodes in a phylogeny does not change the evolutionary relationships that they represent.

If a DNA sequence of the template strand (in the 3'-5' direction) reads ATG, what would be the corresponding mRNA codon (in the 5'-3' direction)?

UAC

A phylogeny is __________.

a figure that shows the branching relationships among populations over evolutionary time

Bats and hummingbirds both have wings and can fly. This is due to__________.

convergent evolution

One of the important facts learned from experiments in molecular genetics is that most amino acids can be encoded by more than one nucleotide triplet. For this reason, we say that the genetic code is __________.

degenerate

A mutation resulting in deletion of a protein-coding gene will most likely have a ___________ effect on fitness.

deleterious

Traits are critical in the study of phylogeny for all of the following reasons, except to __________.

determine the immediate ancestor of an individual

Why are homoplasies problematic in phylogenetic reconstruction?

Homoplasies can result in species with a common trait despite the fact that they are not closely related to each other.