All Flashcards
Define independent assortment.
Genes for different traits are sorted into gametes independently during meiosis.
Define crossing over.
Exchange of genetic material between homologous chromosomes during meiosis I.
Define genotype.
The genetic makeup of an organism.
Define phenotype.
The observable characteristics of an organism, resulting from the interaction of its genotype with the environment.
Define nondisjunction.
Failure of chromosomes to separate properly during meiosis.
Define allele.
A variant form of a gene.
Briefly outline the process of meiosis.
Meiosis I: Homologous chromosomes separate. Meiosis II: Sister chromatids separate, resulting in four unique haploid cells.
What is the role of random fertilization in sexual reproduction?
Random fertilization increases genetic variation by creating unique combinations of alleles.
What is the effect of crossing over on genetic variation?
Crossing over creates new combinations of alleles on the same chromosome, increasing genetic diversity.
What is the effect of nondisjunction during meiosis?
Nondisjunction can lead to gametes with an abnormal number of chromosomes, potentially causing genetic disorders.
How does genetic variation affect natural selection?
Genetic variation provides the raw material upon which natural selection acts, leading to differential survival and reproduction.
What is the effect of random fertilization on offspring?
It increases genetic variation in offspring.