Concept explainers
___ is the original source of new alleles.
- a. Mutation
- b. Natural selection
- c. Genetic drift
- d. Gene flow
- e. All are original sources of new alleles
Introduction: Every organism consists of genes that are made up of DNA. All organisms appear different from one another and also from their ancestors as a result of evolution. Mutation is the key for evolution and the original source for the appearance of new alleles.
Answer to Problem 1SQ
Correct answer: Mutation is the original source of new alleles.
Hence, the correct answer is option a.
Explanation of Solution
Reason for correct answer:
Mutation is a process where a change in the DNA content is inherited to the offspring. Mutation is an alteration in the sequence of an organism's DNA. Mutations can be harmful, but they are sometimes beneficial. They play a vital role in the evolution of an organism or its population. Each and every new genetic trait in an organism will appear as a result of the mutation. This new allele formed as a result of mutation is passed to another through reproduction. Newly formed genetic variant helps an organism to evolve and adapt to unfavorable conditions.
Option a. is given as “Mutation”. Mutation alters the genomic content of an organism and thereby produces new alleles of genes.
Hence, the correct answer is option a.
Reasons for the incorrect answer:
Option b. is given as “Natural selection”. Natural selection is a process where an organism survives an adverse condition by adapting to it. Natural selection does not produce new alleles in organisms, but it takes place after the organisms undergo mutation to adapt to that environment.
Hence, option b. is incorrect.
Option c. is given as “Gene flow”. Gene flow is a process where the genes are transferred from one population to another. Gene flow usually carries out the transfer of genetically varied allele. Therefore, it is not involved in the formation of new allele, but only in transferring it.
Hence, option c. is incorrect.
Option d. is given as “Genetic drift”. Genetic drift is a process where the frequencies of the allele change over generations in a population due to sampling errors. Therefore, it is not involved in the formation of new allele, but only in the measures of change.
Hence, option d. is incorrect.
Option e. is given as “All are original sources of new alleles”. Mutation is the main source of formation of new alleles of a particular gene. This statement is incorrect because all of the above given terms do not lead to form new alleles.
Hence, option e. is incorrect.
Hence, options b., c., d., and e. are incorrect.
Want to see more full solutions like this?
Chapter 17 Solutions
Biology: The Unity and Diversity of Life (MindTap Course List)
- Britain’s Queen Victoria was a carrier for the allele that causes hemophilia and she passed this allele on to some of her descendants. However, there is absolutely no evidence of anyone in Queen Victoria’s ancestry having hemophilia. A-gene flow B-genetic drift C-mutation D-natural selectionarrow_forwardWhich of the following statements about natural selection is a misconception? a.Most species don't produce more offspring than the environment can support b.Natural selection acts on heritable variations in a population c.Natural selection involves differential reproductive success d.Natural selection occurs as a result of competition among individuals in a population e.In natural selection, traits that are favoured depend on current environmental conditionsarrow_forwardDefine a. mutation b. natural selection c. founder effect d. bottleneck e. gene flow f. nonrandom matingarrow_forward
- In the late 1400s, John Cabot and Jacques Cartier made various voyages to what is now known as) Canada. Over the next 200 years, the eastern coastal areas of North America were settled by mostly French, English, and Spanish citizens. What form of genetic drift is represented by the movement of the first European population to North America at this time? Select one: a. Natural selection b. Founder effect c. Controlled breeding d. Bottleneck effectarrow_forwardwhich of these is not a central rule of natural selection a, fitness to the general health and strength of an organism b, natural selection can only act on traits that affect reproduction c, natural selection can't occur without population variation d, a trait must be inherited if natural selection is to act on itarrow_forward3) Movement of alleles between populations is called _____ and results in _____. a.genetic equilibrium; decreased genetic differences between populations b.genetic drift; increased genetic differences between the populations c.gene flow; increased genetic differences between the populations d.genetic drift; decreased genetic differences between the populations e.gene flow; decreased genetic differences between the populationsarrow_forward
- One of the original Amish colonies rose from a ship of colonists that came from Europe. The ship’s captain, who had polydactyly, a rare dominant trait, was one of the original colonists. Today, we see a much higher frequency of polydactyly in the Amish population. This is an example of: a. natural selection b. genetic drift c. founder effect d. b and carrow_forwardBoth mutation rate and population size influence genetic diversity, but they do so to different degrees. Which of the following is WRONG as a comparison of genetic diversity between two populations? O a. Cheetah population (100 individuals ) > Nycterophilia bat flies that live on them d. Forest owlet (between 70 and 400 individuals) >> Ridgway's hawk (maximum 50 individuals) e. cardinalflower (Northeast and South of North America) >> smooth azalea (only in the Eastern seaboard)arrow_forward1. Wood duck is one of the most recognizable birds in the United States. In the late winter season, the males attract the females with their call and colorful markings. The female wood ducks chose their partner based on their attractiveness. They then pair up and begin breeding in the early spring. What mechanism of evolution is described in the given situation? a. natural selection b. genetic drift c. non-random mating d. genetic flow 2. Which of these factors DO NOT produce an adaptive evolutionary change in a given environment? a. natural selection b. none of them c. mutation d. genetic driftarrow_forward
- Galápagos medium ground finches are found on Santa Cruz and San Cristóbal islands, which are separated by about 100 km of ocean. Occasionally, individuals from either island fly to the other island to stay. This can alter the allele frequencies of the population through which of the following mechanisms? a. natural selection b. genetic drift c. gene flow d. mutationarrow_forwardGenetic drift can be defined as Group of answer choices A. accidental changes in DNA structure b.how lazy loci evolve c. random change in allele frequency over time D. differences in fitness between allelesarrow_forwardSickle cell anemia is maintained in human populations because individuals with a single copy of the sickle cell allele have resistance to malaria but lack the health problems of individuals with two copies of the allele. Variation at the sickle cell locus is maintained by which of the following? Group of answer choices A. heterozygote advantage B. random change in allele frequency C. mutation selection balance D. frequency dependent selectionarrow_forward
- Human Heredity: Principles and Issues (MindTap Co...BiologyISBN:9781305251052Author:Michael CummingsPublisher:Cengage Learning