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.
The <em>correct</em> answer is:
Penicillium
Aspergillus
The lesson states:
If you've ever heard of or taken penicillin to fight off an infection, you can thank a member of the imperfect fungi called penicillium. Some mold species of penicillium are also important in the flavoring and aging of cheese. Roquefort and Camembert cheese owe their distinctive flavors to these fungi. Aspergillus is an imperfect fungus that is found on decaying food. It also contributes to the production of organic acids like citric acid. <u>Both penicillium and aspergillus produce enzymes that are purified and used in various industrial compounds and in medicine.</u>
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Answer:
I think the correct answer is D
Answer:Figure: The two stages of photosynthesis: Photosynthesis takes place in two stages: light-dependent reactions and the Calvin cycle (light-independent reactions). Light-dependent reactions, which take place in the thylakoid membrane, use light energy to make ATP and NADPH
Explanation:
<span>Since the child has never been away from his parents and siblings and also he is only 4 years old it is better to have one of them stay with the child. The presence of a family member will reinforce trust and provide support to the kid.</span>