Answer:
See the answer below
Explanation:
<em>The DNA of eukaryotic organisms being present in the nucleus while the protein-synthesizing organelle, the ribosome being present in the cytoplasm poses a spatial problem. It means that transcribed DNAs (messenger RNA) in the nucleus would have to somehow be transported to the ribosome in order for the cell to successfully synthesize proteins.</em>
The problem of transporting the messenger RNA is solved by two features of the cell:
- The presence of pores in the nuclear envelop
- The presence of transport proteins in the nucleus
<u>The mRNA binds to the transport proteins to form mRNA-protein complexes and is transported through the nuclear pores, often with the assistance of ATP. </u>
B, because it's not an advantage for something to be expensive and time consuming
Answer: Option A
<u>Explanation:</u>
As temperature increases the rate of enzyme activity increases until it reaches approximately 37 degrees Celsius. As temperature increases beyond 37 degrees Celsius, the enzyme activity decreases. The activity decreases because the enzyme denatures.
Any enzyme has certain temperature, pH and pressure to maintain its activity. Only at the ideal or ambient parameters the enzyme works. Most of the enzymes that are present in the human body gets activated by 37 degrees and gets denatured beyond that temperature.
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.
