Chapter 4- Genetics: The Science of Heredity Flashcards
Define trait.
a physical characteristic of an organism
Define heredity.
the passing of physical characteristics from parents to offspring
Define genetics.
the scientific study of heredity
Define fertilization.
when the egg and sperm cells join creating a new organism
Define purebred.
the offspring of many generations that have the same form of a trait
Define gene.
a factor that controls traits
Define allele.
each a different form of a gene
Define dominant allele.
an allele whose trait always shows up in the organism
Define recessive allele.
an allele whose trait is hidden in the presence of a dominant trait
Define hybrid.
an organism with two different alleles for a trait
Define probability.
a number describing how likely an event is
Define Punnett square.
a chart that shows all the possible ways alleles can combine in a genetic cross
Define phenotype.
an organism’s physical appearance
Define homozygous.
an organism that has two identical alleles for a trait
Define genotype.
an organism’s genetic makeup, or allele combinations
