Genetic drift occurs when there is no random mating across a population. This causes a change in allelic frequency due to a random sampling of the population.
As the aboriginal population explored the earth, a small part of the population became geographically isolated either due to continental drift and climate changes. As the isolated population grew bigger, they established their own gene pool. This resulted a change in genotypic frequencies from that of the aboriginal population.
For body cells to function properly, the following conditions need to be balanced:
1. BLOOD SUGAR
2. BODY WATER
3. BODY TEMPERATURE.
These three factors have to be in the right proportion for the cells and the body as a whole to function properly and to maintain homeostasis.
Blood sugar is the source of energy in the cell and it is required by all cell for carrying out the normal biochemical reactions in the body. The biochemical reactions in the body use water as a medium of reaction, thus the water balance in the body must be maintained. The body temperature also need to be kept at the normal level or else the normal biochemical reaction of the body will not be able to take place, due to the fact that incorrect temperatures deactivate the enzymes that mediate biochemical reactions.
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.
The two kingdoms are Animalia and Fungi
Answer:
Above
Explanation:
The anthers are always above the stigma.
