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What is 1 + 3?
one of two alternate forms of a gene that can have the same locus on homologous chromosomes and are responsible for alternative traits
threadlike structure within the nucleus containing the genetic information that is passed from one generation of cells to the next
A condition in which neither of two alleles of a gene is dominant or recessive.
genetic inability to distinguish differences in hue
A genetic disorder that occurs in people with two copies of a certain recessive allele; characterized by an excessive secretion of mucus and consequent vulnerability to infection; fatal if untreated.
a cross between individuals that have different alleles for the same gene
an allele whose trait always shows up in the organism when the allele is present
a congenital disorder caused by having an extra 21st chromosome
sequence of DNA that codes for a protein and thus determines a trait
the term for the rules that relate how a sequence of nitrogenous bases in nucleotides corresponds to a particular amino acid
the number and frequency of alleles that are present in a particular population
the science of heredity and of the mechanisms by which traits are passed from parents to offspring
the genetic makeup of an organism
the ratio of the genotypes that appear in offspring
term used to refer to an organism that has two different alleles for the same trait
corresponding or similar in position or structure or function or characteristics
term used to refer to an organism that has two identical alleles for a particular trait
situation in which one allele is not completely dominant over another
A picture of all the chromosomes in a cell arranged in pairs
Unit character-traits controlled by factors (genes) which occur in pairs, Principle of Dominace, Principle of Segregation, and Principle Independent Assortment
a cross between individuals that involves one pair of contrasting traits
three or more forms of a gene that code for a single trait
Product of reproduction, a new organism produced by one or more parents
a diagram that shows the occurrence of a genetic trait in several generations of a family
The physical traits that appear in an individual as a result of its gentic make up.
a ratio that shows the varied outcomes that results from a genetic cross and is based on physical appearance alone
Absence of an enzyme, both recessive alleles must be inherited for the disorder to be displayed
trait controlled by two or more genes
a chart that shows all the possible combinations of alleles that can result from a genetic cross
An allele that will not determine the phenotype unless the genotype is homozygous in that allele
genetically engineered DNA made by recombining fragments of DNA from different organisms
a trait that is determined by a gene found on one of the sex chromosomes, such as the X chromosome or the Y chromosome in humans
sickle cell anemia
a genetic disorder in which erythroctyes take on an abnormal curved or "sickle" shape
recessive disorder that is of the nervous system and the child usually dies by the age of 4
a characteristic that an organism can pass on to its offspring through its genes