Toxicology is the study of poison on living things
Griffith's experiment worked with two types of pneumococcal bacteria (a rough type and a smooth type) and identified that a "transforming principle" could transform them from one type to another.
At first, bacteriologists suspected the transforming factor was a protein. The "transforming principle" could be precipitated with alcohol, which showed that it was not a carbohydrate. But Avery and McCarty observed that proteases (enzymes that degrade proteins) did not destroy the transforming principle. Neither did lipases (enzymes that digest lipids). Later they found that the transforming substance was made of nucleic acids but ribonuclease (which digests RNA) did not inactivate the substance. By this method, they were able to obtain small amounts of highly purified transforming principle, which they could then analyze through other tests to determine its identity, which corresponded to DNA.
<u>Answer</u>:
The organic chemicals that helps cell membranes to conserve the internal fluids are phospholipids.
<u>Explanation</u>:
Phospholipids are used to form plasma membrane of the cell. Plasma membrane surrounds the cell contents like various cell organelles, nucleus, ribosomes and proteins. A phospholipid molecules is made up if a polar head containing a phosphate group and the two non-polar tails made of long chains of hydrocarbon of fatty acids.
The another name for plasma membrane is phospholipid bilayer. The polar head is hydrophilic that interactes with polar environment while facing outside the bilayer while the non-polar tail is hydrophobic in nature which makes the internal hydrophobic region of cell membrane which faces inside the bilayer.
Geologist Alfred Wegner noticed similar rocks & fossils remains were found on Continents which seemed to fit together. He called saw that it was the result of Continental drift and Pangea. Some evidence of the Drift was Rock evidence- Mountain ranges, Glacial scares, Location of coal deposits, ETC..
People couldn't image how the Earth could be millions of years ago. But the 1960's evidence would prove Continental Drift is TRUE and .. the story continues (as all good science!)
Continental drift means that continents move away from each other or separated.
this answer is True; weeds are specific variety of plants that strip the nutrients from the soil.
