Answer:
Factors that cause population growth include increased food production, improved health care services, immigration and high birth rate. These factors have led to overpopulation, which has more negative effects than positive impacts.
Explanation:
The answer is skeleton.
Please correct me if I'm wrong!! :)
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.
Answer:
16/64 = 1/4
Explanation:
This is a typical trihybrid cross involving three genes T, P and Y. A plant with genotype TTPpYy is crossed with a plant recessive for all traits (ttppyy).
According to Mendel's law of independent assortment, each allele for each gene will get sorted into the following 8 gametes with only 4 different: TPY, TPy, TpY, Tpy, TPY, TPy, TpY and Tpy.
The recessive parent, ttppyy will produce tpy, tpy, tpy, tpy, tpy, tpy, tpy and tpy.
Hence, using a punnet square, 64 offsprings will be produced with only 16 of them heterozygous dominant for the three traits with genotype (TtPpYy). Hence, proportion is 16/64 equivalent to 1/4.
