Quiz 2 Flashcards
What was a major difference between Darwin’s theory and the Neo-Darwinism of the early 20th century?
Darwin had no knowledge of the genetic basis for traits being passed from parent to offspring, so his theory was agnostic about exactly how favorable traits were passed on.
What feature or features is most important for determining whether two groups of animals are from the same species or from different species?
Two groups of animals are considered to be from the same species if they can interbreed and produce viable, fertile offspring.
The difference between dominant and recessive traits is
a. recessive traits are deleterious and dominant traits are not.
b. genes for dominant traits are passed on preferentially.
c. dominant genes produce proteins, recessive genes do not.
d. dominant traits are more likely to be expressed in males.
e. effects of recessive traits can be hidden by effects of dominant traits.
E. effects of recessive traits can be hidden by effects of dominant traits
A mule is a hybrid of parents from two different species, horses and donkeys. These species have different numbers of chromosomes: horses have 32 pairs and donkeys have 31 pairs. How many chromosomes does a mule have?
A mule will have 63 chromosomes.
Red-green color blindness in humans is sex linked and recessive. If a male with normal vision marries a woman who is (red-green) color blind …
e. the probability that the daughter will be color blind is 0%
In no more than a few words describe two typical functions that a protein might provide for the organism that produces it.
Proteins are responsible for structure, cell signaling, catalyzing reactions.
What is a SNP? (i.e. What does the acronym stand for?)
A SNP is a single nucleotide polymorphism. It is an alteration of a single base in the genetic code.
Sickle cell trait is a deadly genetic disease that results from a mutation altering the hemoglobin molecule and causing blood cells to rupture. Despite this deadly effect it has been favored by natural selection in parts of Africa and South Asia. How could this deadly gene have been favored by natural selection?
Those who are heterozygous for sickle cell anemia are resistant to malaria, which is a common cause of death in many parts of Africa and South Asia. Individuals with sickle cell anemia fully expressed have high mortality rates, and individuals without sickle cell anemia often die due to malaria. This favors heterozygous individuals, thereby keeping the sickle cell gene in the population.
