A spherical bacterial cell has a radius of 3μm . The human egg cell has a radius of 100μm . Which statement correctly indicates the cell that is able to more efficiently exchange materials with the external environment and provides a correct explanation?

The correct statement would be - the bacterial cell due to the largest surface-to-volume ratio.

Explanation:

The surface area to volume ratio plays a very important role in determining the rate of the diffusion enter and exit from the cell body. If the surface-to-volume ratio is lower then the rate of diffusion would be lower to similarly with an increase in the ratio, the rate of diffusion also increases.

So, the bacteria like small organism have a cell which is exposed to a large surface area to the surrounding in comparison of the human egg cell.

Thus, the correct answer would be - the bacterial cell due to the largest surface-to-volume ratio.

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.

after receiving a stimus, the sensory receptors send(s) signals to the appropriate area of the body.  

the must be sensory neurons.  

hope its .