HEREDITY
& GENETICS
Heredity
� The study of the passing on of traits from
parents to kids.
� Learn how and why physical and behavioral
characteristics are passed on to from parents to
offspring.
Trait
� A person’s behavioral and physical
characteristics.
� Example: brown hair, blue eyes, etc.
� Can also be behavioral such as personality.
Gene
� A specific trait.
� Example: hair color is a trait whereas a gene is the
specific color such as brown.
� Trait = Hair Color / Gene = Brown, Blonde, Red
� Trait = Height / Gene = Tall or Short
� Trait = Personality / Gene = Outgoing, Quiet
Offspring
� A child in relation to its parents.
Phenotype
� A person’s physical characteristics.
� Example: Tall or short, Blonde or brunette, etc.
Gg =
Genotype
� An organisms genetic code represented by
letters.
� Example: AA, Aa or aa
Gg GG
Allele
� The different forms of a trait that a gene
might have.
� Example: GG or Gg
Dominant
� A trait that covers up another trait.
� Example: An uppercase “A”.
Recessive
� A trait that gets covered up by an dominant
trait.
� Example: An lower case “a”.
Homozygous
� Having two identical alleles for a trait.
� Example: AA or aa
Heterozygous
� Having two different alleles for a trait.
� Example: Aa
Purebred
� Both alleles are the same. The same genetic
code is passed on by both parents.
� Example: AA
Hybrid
� The two alleles for a trait are different. The
genetic code that is passed on by each parent
is different.
� Example: Aa
Chromosome
� A threadlike strand that contains DNA and is
found in the nucleus 0f each cell. Humans
have 23 unique chromosomes.
� Example:
DNA
� Found in the chromosomes and transmits
genetic information.
� Example: