Answer:
The correct answer is - 2 genes.
Explanation:
The number of genes involved in the coloration of the strain of cereal grain, could be either dark tan, medium-dark tan, medium tan, light tan, or cream-colored if all F1 are medium tan when crossed a dark tan crossed with cream-colored, can be calculated as follow:
suppose there are only two gene - TT dominant over tt and CC dominant over cc
then the cross would be - RRCC - rrcc
gametes - RC and rc
Cross F1: RrCc
Self cross in F2:
offspring by Punnet cross are:
RRCC -->1/16
RRCc, RrCC .---> 4/16
RrCc, RRcc, rrCC--->6/16
rrCc, Rrcc--->4/16
rrcc ----> 1/16
thus, the correct answer is 2 genes
I think the first option is the answer.
A) toward the earth ...hope this hlep
There are all sorts of ways to reconstruct the history of life on Earth. Pinning down when specific events occurred is often tricky, though. For this, biologists depend mainly on dating the rocks in which fossils are found, and by looking at the “molecular clocks” in the DNA of living organisms.
There are problems with each of these methods. The fossil record is like a movie with most of the frames cut out. Because it is so incomplete, it can be difficult to establish exactly when particular evolutionary changes happened.
Modern genetics allows scientists to measure how different species are from each other at a molecular level, and thus to estimate how much time has passed since a single lineage split into different species. Confounding factors rack up for species that are very distantly related, making the earlier dates more uncertain.
These difficulties mean that the dates in the timeline should be taken as approximate. As a general rule, they become more uncertain the further back along the geological timescale we look. Dates that are very uncertain are marked with a question mark.
