The physical appearance or _____ of an organism is determined by a set of alleles.
A. genotype
B. phenotype
C. transcription
D. translation
The phenotype is the physical appearance of an organism, and the genotype is the set of alleles.
Mendel’s Theory of Heredity
To explain his results, Mendel proposed a theory that has become the foundation of the science of genetics. The theory has five elements:
- Parents do not transmit traits directly to their offspring. Rather, they pass on units of information called genes.
- For each trait, an individual has two factors: one from each parent. If the two factors have the same information, the individual is homozygous for that trait. If the two factors are different, the individual is heterozygous for that trait. Each copy of a factor, or gene, is called an allele.
- The alleles determine the physical appearance, or phenotype. The set of alleles an individual has is its genotype.
- An individual receives one allele from each parent.
- The presence of an allele does not guarantee that the trait will be expressed
Therefore, the Correct Answer is B.