Answer:
1. Brain imaging such as CT scans or MRI's can provide evidence of a brain tumor.
2. Brain tumors are hard to treat because of where they are. The brain is the most delicate organ we have. The nerves, veins, blood vessels and more can make treating the tumor very difficult. Brain surgeries can be so complicated when it comes to tumors because any wrong moves and someone can be impaired for life.
Explanation:
I am going off my general knowledge here. I am not entirely sure but I am trying my best to help. Please let me know if it was close or not.
Lactase refers to an enzyme that can dissociate lactose sugar into glucose and galactose. This enzyme plays an important role in the digestion of milk that comprises high lactose sugar. In case, if a mutation occurs in the gene codon of lactase, then two possibilities can take place. These are as follows:
1. Loss of mutation: In this case, the person becomes lactose intolerant because of mutation in lactase gene codon. Due to this, there is low mRNA expression and thus low production of the enzyme lactase. This is also known as lactase non-persistent phenotype.
2. Gain in mutation: In this case, the person gain an increase in mRNA expression of the lactase gene, thus more production of lactase takes place than usual. This kind of individual exhibits lactase persistent phenotype.
<span>Human weight at the time of birth is influenced by stabilizing selection. Stabilizing selection, also known as negative selection, purifying selection or normalizing selection, is a type of natural selection in which genetic diversity decays according to a particular value of the character. This is the most common mechanism of action of natural selection.</span>
