Deck 7 Flashcards
clone
An organism that is genetically identical to the organism from which it was produced
sexual reproduction
type of reproduction in which cells from two parents unite to form the first cell of a new organism
crossing over
Process in which homologous chromosomes exchange portions of their chromatids during meiosis.
Meiosis I
Separates homologous chromosomes
Meiosis II
sister chromatids separate
Metaphase I
Pairs of homologous chromosomes move to the equator of the cell.
Anaphase I
Homologous chrmosomes move to the oppisite poles of the cell.
Telophase I
Cytoplasm divides, 2 daughter cells are formed
Meiosis I
Homologous chromosomes separate. Ends with the production of 2 haploid daughter cells.
dihybrid cross
A cross between individuals that have different alleles for the same gene
F1 generation
the first generation of offspring obtained from an experimental cross of two organisms
F2 generation
Offspring resulting from interbreeding of the hybrid F1 generation.
Genotype
genetic makeup of an organism
Heterozygous
An organism that has two different alleles for a trait
Homozygous
An organism that has two identical alleles for a trait
law of independent assortment
the law that states that genes separate independently of one another in meiosis
Law of Segregation
first law of heredity stating that pairs of alleles for a trait separate when gametes are formed
Gene
DNA segments that serve as the key functional units in hereditary transmission.
monohybrid cross
A cross between individuals that involves one pair of contrasting traits
P generation
Parental generation, the first two individuals that mate in a genetic cross
Phenotype
An organism’s physical appearance, or visible traits.
Punnett Square
A chart that shows all the possible combinations of alleles that can result from a genetic cross
principle of dominance
Mendel’s second conclusion, which states that some alleles are dominant and others are recessive
Recessive
An allele that is masked when a dominant allele is present
Trait
Characteristics that are inherited
true-breeding
Organisms that, when reproducing, create offspring of all the same variety.
Non-Mendelian Inheritance
A type of inheritance that does not follow strict patterns of dominant vs. recessive
incomplete dominance
situation in which one allele is not completely dominant over another
Codominance
A condition in which neither of two alleles of a gene is dominant or recessive.
sickle cell anemia
hereditary disorder of abnormal hemoglobin producing sickle-shaped erythrocytes and hemolysis
