If a pea plant has a genotype sstt, what are the possible genetic combinations that could be present in a single grain of pollen produced by the plant?

Pollen is essentially a male plant germ cell .

Like all germ cells it is produced in the process of meiosis. In this process, the diploid cells (cells that have two sets of chromosomes) divide into two haploid cells (cells that have one set of chromosomes).

In our example, the diploid mother cell has a SS Tt genotype. This essentially means that the cell has two alleles of the same gene on a different chromosome in the chromosome pair.

When the cell divides, it can give only one allele to the haploid cell.

For the S gene, this cell has two identical dominant alleles( SS genotype), therefore, it can only give the dominant allele to the haploid cell.

As for the T gene, this cell has two different alleles, one dominant and one recessive (Tt genotype) and therefore can give either the dominant (T) or the recessive (t) allele to the haploid germ cell (the pollen).

So, the possible genetic combinations are

ST if the dominant T allele is passed

St if the recessive t allele is passed

americans began to notice growing differences between the northern and southern sections of the country. there were more people living in cities in the north, which made it more urban. more people lived on farms in the south, which made it more rural. while many people were farmers in the northern states, there were now other ways to make a living, such as working in mechanical cotton gins factories manufacturing cloth, tools and other goods. people in the north supported high tariffs on goods imported from europe because the extra cost encouraged people to “buy american” instead. in the southern states, planters did not like tariffs because they sold most of their production to europe and bought their tools from there as well. southerners believed the protective tariff was something that only northern factory owners keep their profits high. so the southern politicians came up with an idea. they would opt out. they would simply ignore the protective tariff. it was ‘null and void’ in south carolina. the state would not collect the taxes on goods imported into south carolina, no matter what the president said they had to do. this decision led to the nullification crisis.

not sure if this is what you'r looking for nnew= nold