- What type of selection occurs when individuals with intermediate phenotypes have higher fitness than those with extreme phenotypes?
A) Directional selection
B) Disruptive selection
C) Stabilizing selection
D) Sexual selection
Answer: C) Stabilizing selection
Explanation: Stabilizing selection favors intermediate phenotypes, reducing variation and promoting traits that enhance survival and reproductive success within a stable environment.
- Which of the following best describes a “founder effect”?
A) A phenomenon where a population experiences increased genetic variation
B) A genetic drift that occurs when a few individuals start a new population
C) A form of natural selection that favors certain traits
D) An increase in gene flow between populations
Answer: B) A genetic drift that occurs when a few individuals start a new population
Explanation: The founder effect occurs when a small number of individuals from a larger population establish a new population, leading to reduced genetic variation and potential differences in allele frequencies compared to the original population.
- Which of the following is NOT a mechanism of evolution?
A) Natural selection
B) Genetic drift
C) Mutation
D) Homeostasis
Answer: D) Homeostasis
Explanation: Homeostasis refers to the maintenance of stable internal conditions within an organism and is not a mechanism of evolution. The other options are all mechanisms that contribute to evolutionary change in populations.
- What does the term “allopatric speciation” refer to?
A) Speciation occurring without geographic barriers
B) Speciation occurring due to physical separation of populations
C) Speciation resulting from behavioral differences
D) Speciation due to temporal isolation
Answer: B) Speciation occurring due to physical separation of populations
Explanation: Allopatric speciation occurs when populations are geographically isolated from one another, preventing gene flow and allowing evolutionary processes to lead to the development of new species.
- Which of the following terms describes the phenomenon where similar traits evolve independently in different species due to similar environmental pressures?
A) Divergent evolution
B) Convergent evolution
C) Parallel evolution
D) Coevolution
Answer: B) Convergent evolution
Explanation: Convergent evolution refers to the process where unrelated or distantly related organisms evolve similar traits as a result of adapting to similar environments or ecological niches.
- What is the significance of the fossil record in understanding evolution?
A) It provides evidence of the age of the Earth.
B) It shows the complete genetic history of species.
C) It documents the existence of species that lived in the past and their changes over time.
D) It is not significant in evolutionary studies.
Answer: C) It documents the existence of species that lived in the past and their changes over time.
Explanation: The fossil record is crucial for understanding evolution as it provides tangible evidence of past life forms, their structures, and how they have changed over geological time, supporting theories of evolution.
- Which of the following processes can lead to increased genetic variation in a population?
A) Stabilizing selection
B) Artificial selection
C) Gene flow
D) Bottleneck effect
Answer: C) Gene flow
Explanation: Gene flow, the movement of alleles between populations, can introduce new genetic variations into a population, thereby increasing its genetic diversity and evolutionary potential.
- What role do mutations play in evolution?
A) They have no impact on evolutionary processes.
B) They provide the raw material for genetic variation.
C) They only lead to harmful changes in species.
D) They ensure all traits are inherited equally.
Answer: B) They provide the raw material for genetic variation.
Explanation: Mutations are changes in the DNA sequence that can introduce new alleles into a population, serving as the fundamental source of genetic variation upon which natural selection and other evolutionary processes act.
- Which of the following statements about artificial selection is true?
A) It occurs only in natural environments.
B) It is the same as natural selection.
C) It is driven by human choices regarding specific traits.
D) It does not affect the genetic makeup of a population.
Answer: C) It is driven by human choices regarding specific traits.
Explanation: Artificial selection is a process where humans selectively breed individuals with desirable traits, impacting the genetic makeup of populations and leading to changes that may not occur naturally.
- Which of the following factors can lead to reproductive isolation?
A) Behavioral differences
B) Geographic barriers
C) Temporal differences in mating seasons
D) All of the above
Answer: D) All of the above
Explanation: Reproductive isolation can occur due to various factors, including behavioral differences (e.g., mating rituals), geographic barriers (e.g., mountains or rivers), and temporal isolation (e.g., different mating seasons), preventing interbreeding between populations.
Leave a comment