Depolarization is initiated when there is an influx of sodium inside the cell as opposed to repolarization, where potassium exits the cell (occurring after Na+ gates close). Remember that for every 3 Na+ in, there is 2 K+ out. This imbalance helps to stabilize the membrane.
Answer:
(C) Aminoacyl-tRNA synthetases have an additional active site that binds to non-cognate tRNAs. The tRNAs that bind to this second active are hydrolyzed and released from the enzyme.
Explanation:
In case of translation, proof reading is done by aminoacyl-tRNA synthetases only. Aminoacyl-tRNA synthetases have two mechanisms to avoid error during translation which are mentioned as under:
<u>(1) Chemical proof reading:</u> Incorrect amino acids rather than being hydrolyzed in catalytic pocket get hydrolyzed in editing pocket and thus they hardly get attached to tRNA.
For example: For distinguishing similar amino acids like isoleucine and valine, isoleucyl-tRNA synthetase uses a second active site which is meant for only valine not for isoleucine. In this particular site, valine which had entered the enzyme is cleaved away with the help of editing reaction after which the enzyme is well prepared to process isoleucine which is the correct amino acid for this enzyme.
<u>(2) Kinetic proof reading: </u>Even if an incorrect amino acid has entered a particular aminoacyl-tRNA synthetase, it does not cause appropriate conformational change in the enzyme because of which the incorrect amino acid loosens from the enzyme and does not get incorporated.
Note: In this example, only chemical proof reading is mentioned not kinetic proof reading.
Answer:
Explanation:
human activities should no be more than the capacity of ecosystem
we should pay attention to carrying capacity of eco system
another one i don't no sorry for that
hope you like my answer and hope it helps you
Answer:
A. Earthquake
Explanation:
When plates slide past each other, the edges of these are earthquake zones. Earthquakes are formed but not volcanoes.
