Chapter 9 - Modern Biology

31 terms by hfinnerty15

Create a new folder

Advertisement Upgrade to remove ads

Heredity

the transmission of characteristics from parents to offspring

Trait

a genetically determined variant of a characteristic

Mendel

the scientist who performed tests on pea plants and discovered dominant and recessive traits

Pollination

occurs when pollen grains from the anthers are transferred to the stigma

Anthers

the male reproductive parts of a flower

Stigma

the female reproductive parts of a flower

Self Pollination

when pollination occurs between the stigma and anthers of the same flower or plant

Cross Pollination

when pollination occurs between the stigma and anthers of different plants and flowers

True Breeding

pure - always produce offspring with their traits when they self pollinate

F1 Generation

the offspring of the P generation - all purple pea pod flowers

F2 Generation

the offspring of the F1 generation - 3:1 ratio of purple to white

Dominant

a trait that masks the factor for the other trait in a pair

Recessive

a trait that is masked by the other trait in a pair

Law of Segregation

states that a pair of factors is separated during the formation of gametes

Law of Independent Assortment

states that factors separate independently from one another during the formation of gametes

Molecular Genetics

the study of the structure and function of chromosomes and genes

Allele

two or more alternative forms of a gene

Genotype

the genetic appearance of an organism

Phenotype

the physical appearance of an organism

Homozygous

both alleles of a trait are alike - ex. RR

Heterozygous

the alleles of a trait are different - ex. Rr

Probability

the likelihood that a specific event will occur

Monohybrid Cross

a cross where only one characteristic is tracked

Punnett Square

a diagram that aids in the tracking of distribution of traits to offspring

Genotypic Ratio

the ratio of the genotypes that appear in offspring - ex. 1 BB : 2 Bb : 1 bb

Phenotypic Ratio

the ratio of the offspring's phenotypes - ex. 3 black : 1 brown

Testcross

a test which determines a genotype of an unknown parent with one that is homozygous recessive (rr)

Complete Dominance

occurs when one allele is completely dominant over the other trait - ex. PP and Pp both express the same trait because P is dominant over p

Incomplete Dominance

occurs when the phenotype of a heterozygote is intermediate between dominant and recessive - ex. A flower with the genotype RR is red and a flower with the genotype rr is white. A flower with the genotype Rr is pink.

Codominance

occurs when both alleles for a gene are expressed in a heterozygous offspring - ex. A boy with the genotype BB has brown eyes. A boy with the genotype bb has green eyes. A boy with the genotype Bb has brown and green speckled eyes.

Dihybrid Cross

a cross in which two characteristics are tracked in a punnett square

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 above and try again

Example:

Reload the page to try again!

Reload

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

NEW! Voice Recording

Create Set