Hereditary and Punnett Squares (Practical 4)

46, diploid

all human somatic (body) cell contain ______ chromosomes = the __________ number

23

how many pairs of homologous chromosomes is in all human somatic (body) cells

genotype

the actual genetic make-up

phenotype

physical expression of the genotype

allele

alternate or varying forms of a particular gene; different versions of a gene

homologous chromosome

one of the two members of eacb pair of human chromosomes

-every somatic (body) cell contains 46 chromosomes, arranged in 23 pairs

gene

an area on a chromosome that codes for a particular protein

-it is the portion of a DNA nucleotide chain that functions as a hereditary unit

trait

a characteristic that is caused by genetics

homozygous

both of the chromosomes in a particular pair carry the same allele

heterozygous

having two different alleles of the same gene

dominant gene

an allele that is expressed in the phenotype regardless of the instructions carried by the other allele

recessive gene

an allele that only gets expressed in the phenotype if it is present on both of the chromosomes of the homologous pair

gregor mendel

what is the father of modern genetics?

offspring

what does punnett squares predict?

reginald punnett

developer of the punnett square, which is used to predict the result of genetic crosses

punett squares

the customary method of working out what the likely offspring of two parents will be

-it is a useful tool that allows you to predict the ratio of offspring and combination various alleles

sex-linked inheritance

inheritance of a trait that can only occur through one of the sex ( X or Y) chromosomes

probality

a measurement that can indicate how likely an event is going to happen

-it is expressed as a number between 0 and 1

-where 0 indicates that it will not occur and 1 indicates that it will always occur

number of specific events or cases/total number of events or cases

what is the formula for probability?

incomplete dominance

a heterozygous conditions in which both alleles are at least partially expressed

zygote

fertilized egg

tastes bitter (PP)

what is the dominant gene for the PTC taster?

no taste (pp)

what is the recessive gene for the PTC taster?

tastes salty, sweet, or bitter (SS)

what is the dominant gene for sodium benzoate taster?

no taste (ss)

what is the recessive gene for sodium benzoate taster?

XX

what is the genotype for females?

XY

what is the genotype for males?

dimples (DD)

what is the dominant gene for dimples?

no dimples (dd)

what is the recessive gene for dimples?

has a widow's peak (WW)

what is the dominant gene for widow's peak?

no widow's peak (ww)

what is the recessive gene for widow's peak?

hair present (HH)

what is the dominant gene for proximal digit finger hair?

no hair present (hh)

what is the recessive gene for proximal digit hair?

has freckles (FF)

what is the dominant gene for freckles?

no freckles (ff)

what is the recessive gene for freckles?

has a blaze (BB)

what is the dominant gene for blaze?

no blaze (bb)

what is the recessive gene for blaze?

blaze

different hair color section