The question asks for the term describing alternative forms of a gene found at the same location on homologous chromosomes. This is a fundamental concept in genetics.
A) Alleles are the alternative forms of a gene that are found at the same locus (position) on homologous chromosomes. For example, in humans, the gene for blood type has three common alleles: IA, IB, and i, which determine the A, B, and O blood types, respectively.
The question asks for the term that describes the observable physical or biochemical characteristics of an organism. This is a fundamental concept in genetics and biology. We need to identify the correct biological term from the given options.
C) Phenotype — The phenotype is the set of observable characteristics of an individual resulting from the interaction of its genotype with the environment. This includes physical traits like height, eye color, and hair color, as well as biochemical traits like blood type or metabolic capabilities.
This question tests basic genetic terminology. It asks for the term describing an individual with two identical alleles for a specific trait. Understanding the definitions of key genetic terms like homozygous, heterozygous, hemizygous, and nullizygous is crucial to answering this question.
C) Homozygous: An individual is homozygous for a trait if they have two identical alleles for that gene. For example, an individual with two dominant alleles (TT) or two recessive alleles (tt) is homozygous.
The question asks to identify the organism that best illustrates incomplete dominance in flower colour inheritance. We need to recall the classic examples of genetic inheritance patterns.
Correct Option: B) Mirabilis jalapa (Four o'clock plant)
The question asks for the F2 phenotypic ratio in a monohybrid cross exhibiting incomplete dominance. We need to recall the principles of incomplete dominance and how it affects phenotypic expression compared to complete dominance.
| R | W | |
|---|---|---|
| R | RR | RW |
| W | RW | WW |
Correct Option: C) 1 : 2 : 1
The question asks to identify the genetic phenomenon where both alleles in a heterozygous individual express themselves fully and independently. We need to recall the definitions of the given options in genetics.
Correct Option: A) Codominance is the phenomenon where both alleles of a heterozygous individual express themselves fully and independently. A classic example is the AB blood group in humans, where both A and B antigens are present on the red blood cells of an individual with genotype IAIB.