01. which arm of tRNA can act as a binding site for ribosomes? 02. Cellular DNA is considered much more stable than the RNA because of:
-anti-parallel nature
-Presence of thymine than uracil
-Extensive repair mechanisms
-none of the above
03. Topoisomerases can break and ligate two broken DNA strands:
-true
-false
04. Renaturation of DNA will result in:
-Hypochromic effect
-Hyperchromic effect
-both
-none
05.A non –coding regulatory DNA sequence that is bound by a regulatory protein can be:
-promoter
-structural genes
-operator
-all
06.In addition to complimentary pairing plays an important role in selection of correct bases:
-Base stacking interactions
-Hydrogen bonding
-Base pair geometry
-none
07.The lagging strand of DNA is copied in short pieces because:
-d. DNA polymerase can synthesize only in one direction
-to decrease mutation rates
-limited space
-to make proof reading easier

it has to be understood that the sea water contains a huge amount of sodium and chlorine ions and if they enter the cell of the atlantic cod fish, the cell will shrivel and the fish will die. to avoid such a condition, the fish uses active transport for the purpose of removing the ions against the gradient.

explanation:

the atlantic cod is not a maritime osmoconformer. its native application of salts is less than that of the seawater it lives in. it is continually falling water from the gills to the ocean via osmosis.

countering that, the fish is going to be swallowing seawater. but since its internal collection of salts is lower than seawater, the fish will want to go free of excess salt, and since that's going upon a gradient, then active transport, requiring energy, must be used to pump out the salt. much marine fish use the organs to filter out the salt and these fish discharge very straight urine.

well the answer is 2!

the law of original horizontality explains:   why rocks appear in layers. correct answer: b the law suggests that all rock layers are originally laid down (deposited) horizontally and can later be deformed.   the principle is used by geologists to make assumptions about the relative ages of sedimentary rocks.