Chapter 4 Science of Genetics

Front

What is a phenotype?

Back

A phenotype is the observable physical or biochemical characteristics of an organism, as determined by both genetic makeup and environmental influences. Example: red hair.

Front

What is codominance?

Back

Codominance is a genetic scenario where both alleles in a heterozygote are fully expressed, resulting in offspring with a phenotype that is neither dominant nor recessive. Example: AB blood type.

Front

What is incomplete dominance?

Back

Incomplete dominance is a genetic situation in which one allele does not completely dominate another allele, resulting in a new phenotype. Example: a red flower crossed with a white flower producing pink flowers.

Front

What is a dominant allele?

Back

A dominant allele is an allele that expresses its phenotype even in the presence of a recessive allele. Example: In a genotype of Aa, 'A' is the dominant allele.

Front

What is a recessive allele?

Back

A recessive allele is an allele that only expresses its phenotype when two copies are present (homozygous). Example: In a genotype of aa, 'a' is the recessive allele.

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What is genetics?

Back

Genetics is the study of genes, genetic variation, and heredity in living organisms.

Front

What is a genotype?

Back

A genotype is the genetic constitution of an individual, represented by the alleles inherited from parents. Example: AA, Aa, or aa.

Front

What is the difference between genotype and phenotype?

Back

Genotype refers to the genetic makeup of an organism, while phenotype refers to the observable traits or characteristics.

Front

What is a homozygous genotype?

Back

A homozygous genotype has two identical alleles for a particular gene. Example: AA or aa.

Front

What is a heterozygous genotype?

Back

A heterozygous genotype has two different alleles for a particular gene. Example: Aa.