Genetics Flashcards
Is the study of heredity. Genetics involves studying how traits are passed from parents to offspring
Genetics
Is the passing of traits from parents to offspring
Heredity
Are the characteristics of an organism. Examples are eye color, freckles, height or dimples
Traits
Chromosomes are thread-like structures in the nucleus of cells that carry genetic information. A chromosome consists of a long strand of DNA containing many genes
Chromosomes
Deoxyribonucleic acid (DNA) is a molecule made up of nucleotides that contains genetic information for cell growth, division and function
DNA
A gene is a segment on a chromosome that determines a specific trait. Genes are the units of heredity
Gene
A different form or version of a gene - alleles usually occur in pairs
Allele
A gene variant that is expressed more strongly than other versions of the same gene - the dominant allele masks the effect of the recessive allele
Dominant
A gene that is masked by a dominant gene, and is only expressed when two copies of the gene are present
Recessive
The genetic make up or code of an organism - Ex: BB, Bb, bb
Genotype
The observable traits or physical appearance of an organism - Ex: brown eyes or blue eyes
Phenotype
If an organism has two of the same kind of gene for a trait, it is called pure or homozygous.
Example: Homozygous brown eyes (BB) ~ Homozygous blue eyes (bb)
Homozygous
An organism with two different alleles for a trait is called heterozygous or hybrid.
Example: A heterozygous tall plant (Tt) expresses the dominant allele (T or tall) and thus, is tall
Heterozygous
