🧬 AP Biology Study Guide: Patterns of
Inheritance
🔑 I. Foundational Genetic Concepts
Term Definition
Gene A heritable unit that codes for a protein and
determines a trait. Located on chromosomes.
Locus The physical location of a gene on a
chromosome.
Allele Alternate versions of a gene that may result
in different phenotypes.
Genotype The genetic makeup of an individual (e.g.,
Aa, BB).
Phenotype The observable traits of an individual (e.g.,
tall, blue eyes).
Homozygous Having two identical alleles (AA or aa).
Heterozygous Having two different alleles (Aa).
Carrier A heterozygous individual who has a
recessive allele but does not express the trait.
🧪 II. Mendel's Laws of Inheritance
🌱 1. Law of Segregation
● Alleles for a gene segregate during gamete formation (meiosis I).
● Offspring inherit one allele from each parent.
🧬 2. Law of Independent Assortment
Inheritance
🔑 I. Foundational Genetic Concepts
Term Definition
Gene A heritable unit that codes for a protein and
determines a trait. Located on chromosomes.
Locus The physical location of a gene on a
chromosome.
Allele Alternate versions of a gene that may result
in different phenotypes.
Genotype The genetic makeup of an individual (e.g.,
Aa, BB).
Phenotype The observable traits of an individual (e.g.,
tall, blue eyes).
Homozygous Having two identical alleles (AA or aa).
Heterozygous Having two different alleles (Aa).
Carrier A heterozygous individual who has a
recessive allele but does not express the trait.
🧪 II. Mendel's Laws of Inheritance
🌱 1. Law of Segregation
● Alleles for a gene segregate during gamete formation (meiosis I).
● Offspring inherit one allele from each parent.
🧬 2. Law of Independent Assortment
