At an autosomal gene locus in humans, the allele for brown eyes is dominant over the allele for blue eyes. at another gene locus, located on the x chromosome, a recessive allele produces colorblindness while the dominant allele produces normal color vision. a heterozygous brown-eyed woman who is a carrier of colorblindness has children with a blue-eyed man who is not colorblind. what is the probability that their first child will be a brown-eyed, colorblind male?

If we name the gene for the eye color with A, then the genotypes for the brown color would be AA, Aa and the genotype for the blue eyes aa.

If we name the gene for the colorblindness with B, then the genotype XbXb is for colorblind woman while XBXb and XBXB are genotypes for the woman with normal vision.

A heterozygous brown-eyed woman who is a carrier of colorblindness has genotype: Aa XBXb and a blue-eyed man who is not colorblind:  aa XBY.

P:  Aa  XBXb  x  aaXBY

F1: (Aa Aa aa aa) ½ or 50% is the probability for the brown eye, ¼ or 25% is the probability that the child would be color blind male (XBXB XBY XbXB XbY)

This means:probability that their first child will be a brown-eyed, colorblind male is ½*1/4=  1/8= 12.5%

the farther away the object is from the central star (the sun) it's gravitainal pull on the object is weaker when it is farther

explanation:

the correct answer is - d. china has a large and growing population.

the fact that china has a large (the biggest) population, and it is still growing, doesn't hinder the agriculture production in the country. in fact, it can for increased production in the agriculture, since there's more labor force, as well the sheer mass of people produces lots of scientists that come up with new inventions as to how to improve this sector. nice example is the inner mongolia region in china, in general dominated by the gobi desert, but few scientist came up with a nice idea as to how to make the region productive by using plants that are very resistant to droughts, so lots of people have been employed, and the region is becoming greener and greener each year, and the production of food in this region is also increasing.