What is one way that biotechnology can most directly improve the marine environment? a. Through the use of genetically engineered salmon released to enhance wild salmon populations
b. Through the use of larger salmon released into the environment to consume nuisance fish
c. Through the use of new technologies and methods for cleaning oil spills in beaches and the ocean
d. Through the use of new technologies to make obtaining deeply-buried fossil fuels more cost effective

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.

unicellular organisms, like bacteria, are able to perform all life functions within one single cell. multicellular organisms need many different types of cells to carry out the same life processes. each of these special types of cells has a different structure that it perform a specific function.