Answer:
a). At least one intron must be present in gene X.
b). At least two intron must be present in gene Y
c). It is impossible to determine whether there are any introns in gene Z.
Explanation:
Introns may be defined as the segments in the RNA molecule or the DNA molecule that does not code for proteins and they interrupts the sequences of each of the molecules.
In the context, we get :
a). In the gene X, at least one of the intron is present. Sometimes more than one introns may also be present. Due to slicing, we get one band less in the cDNA which is made from the mRNA.
b). In dene Y, at least one intron is present. Sometimes more than one introns are present inside the gene Y. In this case we get two bands less in the gene due to slicing.
c). In gene Z, it is not possible to determine the number of introns present in them. In genes X and Y, the Haelll enzyme is present in the intron. Therefore we get less of band after splicing the mRNA to cDNA.
The answer is c) a number and a unit
Macrophages are phagocytic cells which are involved in endocytosis. It is a process of engulfing antigen. Endocytosis occurs when a cell destroys something such as a virus or an infected cell.
The correct steps of endocytosis in chronological order as follows:
6. Cell recognizes the viral particle as foreign material.
1. Cell surface receptors bind to the viral particle.
4. Cell membrane curves around toward the cell's interior.
3. Viral particle is surrounded by the cell membrane.
2. Lysosome within the cell encloses the viral particle.
5. Lysosome's digestive enzymes destroy the viral particle.
Beans, because they contain protein. When it comes to building and repairing, protein is most likely your answer. We know that pasta is not the answer because it is a large source of carbohydrates and most often used for carbo-loading.