In Drosophila, a mutation caused a gene to be relocated close to the centromere. In flies with this mutation, some cells expressed the gene, while the gene remained silent in other cells (of the same cell type). This position effect variegation is due to ___.

white blood cells or wbc s are mainly 2 types-

1.agranulocytes

2.granulocytes

the monocytes or macrophages of agranulocytes , dendritic cells which are accessory leucocytes, and b cells which is one type of lymphocytes   identify the antigens present on the pathogen's surface. these three cells are called antigen presenting cells(apc) which are phagocytes and destroy the antigens by secreting antitoxins. besides this leukocyte is always plays vital role in the immunity of the body.

1. loamy sand is about 80% sand with 10% clay and defined mostly by sand particles with some clay to provide structure and fertility. the sand particles are easily visible and the soil holds structure but breaks apart easily.

2. scott sand can improve his soil quality by incorporating more silt and organic matter into the soil. peat moss and organic matter can also be incorporated.

rising temperatures because when water vapor in the air is cooled, it condenses. it turns back into a liquid and attaches to dust particles in the air. these very small water droplets group together to form clouds