science Flashcards
heredity
the passing of genetic traits from parent of offspring
dominant trait
the trait observed in the first generation when parents that have different traits are bred
recessive trait
a trait that reappears in the second generation after disappearing in the first generation when parents with different trails are bred
gene
one set of instructions for an inherited trait
allele
one of the alternative forms of a gene that governs a characteristic, such as hair color
phenotype
an organism’s appearance or other detectable characteristic
genotype
the entire genetic makeup of an organism; also the combination of genes for one or more specific traits
Probability
the likelihood that a possible future event will occur in ant given instance of the event
Meiosis
a process in cell division during which the number of chromosomes decreases to half the original number by two divisions of the nucleus which results in the production of sex cells
Sex chromosomes
one of the pair of chromosomes that determine the sex of an individual
Pedigree
a diagram that shows the occurrence of a genetic trait in several generations of a family
DNA
deoxyribonucleic acid a molecule that is present in all living cells and that contains the information that determines the traits that a living thing inherits and needs to live
Nucleotide
in a nucleic-acid chain a subunit that consists of a surgar a phosphate and a nitrogenous
Mutations
a change in the nucleotide-base sequence of a gene or DNA molecule
RNA
ribonucleic acid a molecule that is present in all living cells and that plays a role in protein production
