In some bees, thin stripes (s) are dominant over thick stripes (s) and black eyes (b) are dominant over gray eyes (b). complete a dihybrid cross for parents with the genotypes: ssbb × ssbb and answer the following in complete sentences.

describe how you would set up a punnett square for this cross.
list the likelihood of each possible offspring genotype.
list the likelihood of each possible offspring phenotype.

Genotypic Ration -

SsBB: ssBB: SsBb:ssBb  is 4: 4:4:4

Likelihood of occurrence is  

SsBB: 25 %

ssBB: 25 %

SsBb:25 %

ssBb:25 %

Phenotypic ratio -

thin striped black eye :  thick striped black eye

8 : 8

1: 1

Likelihood of occurrence is  

thin striped black eye :  50%

thick striped black eye : 50%

Explanation:

The genotype of  two parents is SsBB and ssBb

The alleles for cross for parent with genotype SsBB are  SB, SB, sB, SB

The alleles for cross for parent with genotype ssBb are sB, sb, sB, sb

The cross between the two parents is represented by a punnet square as given below -

        SB          SB          sB         sB

sBSsBBSsBBssBBssBB

sbSsBbSsBbssBbssBb

sB SsBBSsBBssBBssBB

sbSsBbSsBbssBbssBb

Genotypic ratio

SsBB: ssBB: SsBb:ssBb  is 4: 4:4:4

Likelihood of occurrence is  

SsBB: 25 %

ssBB: 25 %

SsBb:25 %

ssBb:25 %

As given thin stripes (S) are dominant over thick stripes (s) and black eyes (B) are dominant over gray eyes (b).

So the phenotype for genotype of offsping is as follows

SsBB: thin striped black eye

ssBB: thick striped black eye

SsBb: thin striped black eye

ssBb: thick striped black eye

Phenotypic ratio -

thin striped black eye :  thick striped black eye

8 : 8

1: 1

Likelihood of occurrence is  

thin striped black eye :  50%

thick striped black eye : 50%

burning fossil fouls really decrease the carbon in the atmosphere so b

answer: the correct option is d. enzyme

lactase and carbonic anhydrase are the examples of enzymes.

lactase is an enzyme, which is present in the small intestine of mammals. it in the digestion of the disaccharide, lactose ( milk sugar) by converting it into two monosachharide, which are glucose and galactose.

carbonic anhydrase is present in the red blood cells. this enzyme plays significant role in the transport of co₂. it in the conversion of co₂ and h₂o into carbonic acid, which is then dissociated into bicarbonate ions and hydrogen ions.