The right answers are:
A-present in eukaryotic genomes ==> Both exons and introns
B-generally absent from bacterial genomes ==> Introns
C-part of the final mRNA strand ==> Exons
D-code for an amino acid sequence ==> Exons
E-removed from initial mRNA strand prior to translation ==> Introns
F-present in the DNA used as the template for transcription ==> Both exons and introns
In the genes of eukaryotic organisms, the exons are the segments of an RNA precursor that are conserved in the RNA after splicing and that are found in mature RNA in the cytoplasm. The segments of the RNA precursor that are removed during splicing are called in opposition to introns. Exons are mainly found in messenger RNAs (mRNAs) encoding proteins. Some mRNAs may sometimes undergo an alternative splicing process in which one or more exons may be excised or some introns preserved in rare cases.
Lysosomes, dead organelles, waste products and other unwanted substances are removed through lysosomes
The synaptic pruning during childhood results in a reduction in density of nerve cells, thus increasing the brain's efficiency.
<span>Synaptic pruning, which can include both axon and dendrite pruning, is the process of synapse elimination that occurs usually in early childhood. It is thought that this is the brain’s way of removing connections in the brain that are no longer needed and a way of maintaining more efficient brain function.</span>