Simple version:
First, the section with the desirable gene must be identified. Assuming that has already happened, the section of DNA must be excised from the original genome using restriction enzymes, which recognize certain DNA sequences and snip DNA at those sites. DNA ligase is used to "glue" these ends back together. The DNA is inserted into a plasmid (also with restriction enzymes), which would usually contain antibiotic-resistance genes (so they survive in an environment containing the antibiotic, which would also help show if the bacteria have been successfully transformed).
Then comes the actual transformation process. The bacteria to be transformed are mixed with calcium chloride (which causes the bacteria to be more receptive to the plasmids) and then mixed with the plasmids. The bacterial cells are subjected to a heat shock (the solution is heated and rapidly cooled, e.g. by placing the mixture in a hot water bath and quickly transferred to ice) so they will take up the plasmid (since the temperature change makes the membrane more permeable). The bacteria are placed on a growth medium containing the antibiotic they're resistant to. Only those successfully transformed would survive.
Answer:
C. surface tension
Explanation:
Surface tension refers to the property of water or any liquid to enhance its surface area by a certain amount. It is a very important property of water due to which it resists any external force due to cohesive nature of water molecules.
How surface tension help needle to float on water:
It is a property of water which enhance the attractive force between needle and liquid.
The molecules on the surface of water do not have any force acting from upwards because that side is exposed to atmosphere. This causes a downward force but no upward force on upper surface,so the molecule of surface tend to stay together by forming a thin sheet or imaginary layer.
If weight of any material cannot break surface tension it will float on water surface. This is what happens with needle.Therefore, when needle is placed on water surface with alot of care in horizontal direction, it will not break surface tension and hence will float on water. Please see attached image for better understanding.
Hope it clears up the picture!
The answer is C because the lions eat the zebras and the gazelles which are the primary consumers and the trees would be considered the producers.
Energy is maximum at the level of producers, and then decreases upwards; only 10% of energy is carried on to the next trophic level.
Hence, an energy pyramid diagram for ecosystem studies shows a triangular shape.
I hope this helps
