Chapter 3 Flashcards
Heredity
The passing of physical characteristics from parent to offspring
Trait
A specific characteristic
Genetics
The scientific study of heredity
Fertilization
A new organism that forms when egg and sperm cells join in this process
Purebred
The offspring of many generations that have the same form of trait
Gene
To describe the factors that control a trait
Alleles
The different forms of a gene
Dominant allele
One whose trait always shows up in the organism when the allele is present
Recessive allele
Is hidden when the dominant allele is present
Hybrid
Has 2 different alleles for a trait
Probability
A number that describes how likely it is that an event will occur
Punnett square
A chart that shows the possible ways alleles can combine in a genetic cross
Phenotype
Physical appearance, visible traits
Genotype
Genetic makeup, alleles
Homozygous
An organism that has 2 identical alleles for a trait
Heterozygous
An organism that has 2 different alleles for a trait
Incomplete dominance
Occurs when one allele is only partially dominant
Codominance
Occurs when both alleles for a gene are expressed equally
Multiple alleles
Which means that three or more possible alleles determine their trait
Polygenic inheritance
Occurs when more than one gene affects a trait.
