Question

Why is sexual reproduction so common in higher multicellular organisms such as humans?

a) It increases genetic variation
b) It ensures identical offspring
c) It reduces the need for mate selection
d) It expedites the reproductive process

Answer 1

Sexual reproduction is common in multicellular organisms due to its ability to increase genetic variation, which is essential for population survival and adaptation to environmental changes.

Step-by-step explanation:

Variation is crucial for the survival and reproduction of a population, particularly as it allows a population to adapt to changing environments. The primary mechanisms through which sexual reproduction introduces variation include the random assortment of chromosomes during meiosis, crossovers during prophase I, and the unique combination of parental genomes. Contrary to asexual reproduction, where the only source of variation is mutation, sexual reproduction reshuffles these mutations, thus continually creating diverse combinations of genes. This genetic diversity is advantageous because it can result in offspring with diverse phenotypes that may be better suited to survive environmental changes, and on average, a sexually reproducing population will leave more descendants than an asexually reproducing one.