Since Lithium has one valence electron that means it needs to lose it to form a stable structure. That means it's valence is equal to one. Oxygen has six atoms, in order to form a stable octet structure it needs to accept 2 electrons, therefore it's valence is 2.
Therefore two Lithium atoms bond with one oxygen atom to form Li2O
Animal cells communicate via their extracellular matrices and are connected to each other via tight junctions, desmosomes, and gap junctions
ans is D. Most items are features in the spinal cord, but the hippocampus is in the brain.
Answer:
A
Explanation:
The restriction enzymes cut the isolated DNA into fragments
These genes could have arisen by gene duplication.
<h3>What is gene duplication?</h3>
Gene duplication is the process of copying a section of DNA that codes for a gene. A retro transposition event or a recombination mistake are both potential causes of gene duplication. As a result, the duplicate gene coding may experience a significant number of modifications throughout time. This might prevent the gene from functioning or, in other situations, give the creature a benefit.
Gene duplication is a phenomenon that can happen through a variety of ways:
- Ectopic Recombination: Uneven crossing-over between misaligned homologous chromosomes during meiosis might result in duplications. A duplication at the exchange site and a reciprocal deletion are the results of this recombination.
- Replication Slippage: Short genomic sequences can be duplicated as a result of the replication error known as replication slippage. DNA polymerase starts copying the DNA during replication, but eventually the polymerase separates from the DNA, causing replication to stall. The replicating strand is incorrectly aligned when the polymerase reattaches to the DNA strand, which accidentally results in several copies of the same portion.
- Aneuploidy: When a single chromosome's nondisjunction causes an abnormally high number of chromosomes, this condition is known as aneuploidy. Aneuploidy is frequently damaging and frequently causes spontaneous miscarriages in mammals. Some aneuploid people can survive. For instance, human trisomy 21 causes Down syndrome but is not lethal.
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