Answer:
Darwin's research on Galapagos Island put forward his theory of natural selection.
Explanation:
1. Charles Darwin studied the similarities of the finches between the various islands of Galapagos. His study noted that the finches were similar from island to island making him to wonder about the origin of this species as these perfectly adapted to their environment. His compilation of observation about the finches, the fastest evolving vertebrates, described its behavior and appearances which changed according to the changing environment., thus making them to adapt quickly. These were further converted for his book 'The Origin of Species' that changed the concept of evolution.
2. Grants research on Galapagos Islands were conducted by Peter Raymond Grant and Barbara Rosemary Grant, both evolutionary biologists. Their work focussed on the Darwin's finches through processing of collecting blood samples and tagging them. They were able to indicate that changes within the species is evident within a single lifetime. Their study indicted that changes in populations takes place quickly and need not wait for long time as indicated in Darwin's theory.
3. The Galapagos Island is a ground to more species that have risen due to adaptation. Due to its remote location, it was possible for the scientists to conduct study about natural selection on biodiversity. THere are 18 species that have evolved from Darwin's finches. The diversification observed in the finches were the shape and size of beaks.
The Darwin's finches developed over time with strong crushing and probing beaks adapted to catch insects or crack nuts. Even some have sharp long beaks to drink blood.
Another species observed is the marine Iguana with adapted short blunt stout, and long tail to swim deep into sea.
The flightless cormorant found in this island, were adapted to survive as there was no necessity to fly. Instead their dense bodies, small feet, and powerful legs makes them to be good divers to hunt fish, eels, and small octopus.
The right answer is: The antibodies mistakenly identify the cells as foreign material.
The role of an antibody is to recognize a foreign antigen in order to neutralize it. They can achieve this thanks to the great specificity of their paratope, which recognizes only a very precise part of the antigen: the epitope. As soon as an antibody recognizes an epitope, the B lymphocyte that codes for that specific antibody multiplies and matures in order to synthesize the same antibodies, useful in large quantities.
The phenomenon described in the question is an autoimmunity mediated by autoantibodies.
An autoantibody is an antibody produced by the immune system and directed against one or more proteins of the individual himself
Many autoimmune diseases are due to the presence of these autoantibodies, but the presence of autoantibodies is not necessarily synonymous with such a disease.
Some scientists say that they could have a beneficial role in cleaning up cell debris resulting from a disease.
The way in which these autoantibodies are produced, their precise role, and the reason why they decrease in individuals with certain diseases, are all issues that remain unresolved.
<span>Only one sperm normally fuses
with an egg because if more than one sperm fuses, through a process
called polyspermy, development of the zygote usually stops.
</span>
<span>Fertilization of one egg by
two sperm is possible, but the resulting zygote is almost never viable
because such a zygote would have three sets of chromosomes instead of
the normal two. This condition, called triploidy, is usually
incompatible with life. Those rare triploid infants that do survive to
term have severe and multiple birth defects and rarely live more than a
few days. </span>
Answer:
Option-A
Explanation:
Pentose phosphate pathway is the alternative pathway taking place in both eukaryotes and prokaryotes parallel to the glycolysis.
The pentose phosphate pathway forms the electron carriers called NADPH and the ribose-5 phosphate.
The NADPH is formed in large amounts through this pathway which contains a very high amount of energy. NADPH can donate its hydride ions, therefore, it can be involved in the reaction where it can donate energy in the form of hydrogen and electron.
The NADPH is therefore involved in the formation of reducing biosynthetic pathways like fatty acid synthesis, cholesterol synthesis, and bile acid synthesis.
Thus, Option-A is the correct answer.
Ans: Most genes contain the information needed to make functional molecules called proteins. (A few genes produce regulatory molecules that help the cell assemble proteins.) The journey from gene to protein is complex and tightly controlled within each cell.
