Like this study set? Create a free account to save it.

Sign up for an account

Already have a Quizlet account? .

Create an account

gene interaction

a situation in which a single phenotype is affected by more than one set of genes


a case where genes are present on the X chromosome


mutations that produce alleles that encode proteins with reduced or no function

if the loss is complete from a loss-of-function mutation, the mutation results in

a null allele


mutation that produces a phenotype different from that of the normal allele and from any loss-of-function alleles

incomplete dominance

expressing a heterozygous phenotype that is distinct from the phenotype of either homozygous parent (aka partial dominance)

Tay-Sachs disease

homozygous recessive individuals are severely affected with a fatal lipid-storage disorder and neonates die during their first one to three years of life

threshold effect

normal phenotypic expression occur anytime a certain level of gene product is attained


when two alleles of a single gene are responsible for producing two distinct, detectable gene products

multiple alleles

three or more alleles of the same gene

H substance

the connection of sugars by which one and/or two sugars can be added resulting in the A, B, or AB blood types

bombay phenotype

a rare variant of the ABO antigen system in which affected individuals do not have A or B antigens and thus appear to have blood type O, even though their genotype may carry unexpressed alleles for the A and/or B antigen

recessive lethal allele

mutations that result in the synthesis of a gene product that is non functional can often be tolerated in the heterozygous state
one wild-type allele may be sufficient to produce enough of the essential product to allow survival

gene interaction

term used to express the idea that several genes influence a particular characteristic


the idea that an organism or organ arises trhoguht eh sequential appearance and development of new structure, in contrast to preformationism

hereditary deafness

mutations that interrupt many of the steps of ear development lead to a common phenotype called this


the expression of one gene pair masks or modifies the effect of another gene pair

complementation group

all mutations determined to be present in a ny single gene are said to fall into this group


condition in which a single mutation caused multiple phenotypic effects

marfan syndrome

a human malady resulting from an autosomal dominant mutation in the gene encoding the connective tissue protein fibrillin


genes present on the X chromosome exhibit patterns of inheritance that are very different from those seen with autosomal genes

chromosome theory of inheritance

the correlation between mendel's work and the behavior of chromosomes during meiosis

sex-influenced inheritance

phenotypic expression conditioned by the sex of the individual. a heterozygote may express one phenotype in one sex and an alternate phenotype in the other sex

sex-limited inheritance

a trait that is expressed in only one sex even though the trait may not be X-linked

Please allow access to your computer’s microphone to use Voice Recording.

Having trouble? Click here for help.

We can’t access your microphone!

Click the icon above to update your browser permissions and try again


Reload the page to try again!


Press Cmd-0 to reset your zoom

Press Ctrl-0 to reset your zoom

It looks like your browser might be zoomed in or out. Your browser needs to be zoomed to a normal size to record audio.

Please upgrade Flash or install Chrome
to use Voice Recording.

For more help, see our troubleshooting page.

Your microphone is muted

For help fixing this issue, see this FAQ.

Star this term

You can study starred terms together

Voice Recording