Ch.7 - Genetics: The Science of Heredity
Standards:
7.LS3.2 - Distinguish between mitosis and meiosis and compare the resulting daughter cells.
7.LS3.3 - Predict the probability of individual dominant and recessive alleles to be transmitted from each parent to offspring during sexual reproduction and represent the phenotypic and genotypic patterns using ratios.
Important Vocabulary:
Heredity - the passing of traits from parent to offspring.
Trait - A specific characteristic that an organism can pass to its offspring through its genes.
Genetics - the scientific study of heredity.
Fertilization - the process in sexual reproduction in which an egg cell and a sperm cell join to form a new cell.
Purebred - an offspring of crosses that has the same form of traits.
Gene - a sequence of DNA that determines a trait and is passed from parent to offspring.
Alleles - the different forms of a gene.
Hybrid - an offspring of crosses that has two different alleles for a trait.
Phenotype - an organism's physical appearance, or visible traits.
Genotype - an organism's genetic makeup, or allele combinations.
Summary
An organism's traits are controlled by the alleles it inherits from its parents. Some alleles are dominant, while other alleles are recessive. In a genetic cross, the combination of alleles that parents can pass to an offspring is based on probability. An organism's phenotype is its physical appearance, or visible traits. An organism's genotype is its genetic makeup, or alleles. Most traits are the result of complex patterns of inheritance. Environmental factors can influence the way genes are expressed. The chromosome theory of inheritance states that genes pass from parents to their offspring on chromosomes.
Phenotypes make up organism's physical appearances.
A trait is a characteristic passed from parent to offspring through genes.
