DNA Mutations and Evolution

What causes base pair changes (mutations) in DNA according to the learning material?

• Natural selection

• Mendelian descent

• Environmental factors and copying mistakes

• Phenotype changes

How does mutation in the genotype affect an organism?

• It does not introduce any changes.

• It creates changes in the DNA sequence only.

• It creates changes in the phenotype, introducing variation in the species.

• It prevents natural selection from occurring.

What is the role of natural selection in evolution?

• It causes mutations in the genotype.

• It acts on the variation introduced by mutations.

• It ensures that all offspring are identical.

• It changes the DNA sequence directly.

How are new genetic codes passed to offspring?

• Through environmental factors

• By natural selection

• By Mendelian descent

• They are not passed to offspring

What does the term "genotype" refer to?

• The physical appearance of an organism

• The combination of alleles that characterize an individual at some set of genetic loci

• The structure of DNA

• The observable characteristics of an organism

What is the "phenotype" of an organism?

• The genetic makeup of an organism

• The combination of alleles that characterize an individual at some set of genetic loci

• The observable characteristics of an organism

• The structure of DNA

Which of the following is not a base in DNA?

• Adenine

• Thymine

• Uracil

• Guanine

What is the function of the phosphate backbone in DNA?

• It encodes genetic information.

• It connects the DNA bases together.

• It forms the structural framework of the DNA molecule.

• It is responsible for the replication of DNA.

What defines the phenotype of an organism?

• The environment

• The genotype

• The phenotype itself

• Random chance

Which organisms are exceptions to having different genotypes?

• Siblings

• Twins or clones

• Cousins

• Species