Question

Eyelash length is an inherited trait. In the human population, there is an eyelash length gene. There are two possible variants of this gene - an allele for long eyelashes (> 1cm) and an allele for short eyelashes (1 cm or less). The allele for long eyelashes is dominant (L) and the allele for short eyelashes is recessive (l). An individual who is heterozygous for eyelash length would produce which of the following gametes?

A. All gametes would have the l allele.
B. All gametes would have the L allele.
C. Half of the gametes would have the L allele and half of the gametes would have the I allele.
D. The proportion of gametes receiving each allele would be random; the process of meiosis is very disorganized and chromosomes are not separated in an ordered fashion.
E. None of the gametes would have the eyelash gene; gametes do not have eyelashes.

Answer 1

Option C is correct. An individual with heterozygous eyelash length genes (Ll) would produce half of the gametes with the dominant allele (L) and half with the recessive allele (l), following Mendel's law of segregation during meiosis.

Step-by-step explanation:

Eyelash Length Genetics

In genetics, the inheritance of traits such as eyelash length follows Mendelian principles. Since the allele for long eyelashes (L) is dominant over the allele for short eyelashes (l), an individual with heterozygous eyelash length genes (Ll) would produce two types of gametes. During meiosis, which is an organized process, alleles segregate so that each gamete receives only one allele from each gene. Consequently, an individual with heterozygous eyelash length (Ll) would produce half of the gametes with the dominant allele (L) and half with the recessive allele (l).

Half of the gametes would have the L allele and half of the gametes would have the l allele. This is because during meiosis, the two alleles for a gene segregate into different gametes, following the law of segregation. The process of meiosis is highly organized and ensures that chromosomes and their respective alleles are separated in an orderly fashion.

Therefore, the proposition that the proportion of gametes receiving each allele is random or disorganized (as in option D) is incorrect. The answer is not option A or B as both suggest all gametes would contain only one type of allele, disregarding the separation of alleles during meiosis. Finally, option E is incorrect and irrelevant, as it brings a non-genetic characteristic (the presence of actual eyelashes on gametes) into the explanation, which does not relate to the genetic nature of the question.