Question

How do DNA sequences or genes control phenotypes?

Answer 1

Phenotype:

1. A phenotype is the set of physical characteristics that an organism expresses.
2. Gene expression, random genetic variation, environmental factors, and an individual's genotype all contribute to the phenotype.
3. The phenotype of an organism is determined by its genotype.
4. DNA, which contains the instructions for creating molecules, cells, tissues, and organs, is present in all living things.
5. All cellular processes, including mitosis, DNA replication, protein synthesis, and molecular transportation, are guided by the genetic code found in DNA.
6. Genes are specific DNA sections that encode for the creation of proteins and specify unique characteristics.
7. Every gene has several variants and is found on a certain chromosome.
8. These variants are called alleles.
9. An organism is homozygous for a characteristic if it inherits two copies of the same allele for that trait.
10. One phenotype for a particular characteristic is expressed in homozygous individuals.
11. An organism is heterozygous for a trait if it inherits two distinct alleles for that trait. Individuals that are heterozygous for a trait may display more than one phenotype.