Landfills are waste disposal sites. They are often man made depressions in the ground covered with a lining designed to prevent any leakage of waste materials. However, landfills can leak through the base resulting in negative impacts on the surrounding environments. What negative impact to the environment is caused by the production of methane gas in landfills?

Select one:
a. air pollution
b. soil fertility
c. groundwater pollution
d. air pollution, groundwater pollution, soil fertility

Which is an advantage of having memory cells when a pathogen is encountered for a second time. a) the memory cells are what proliferate into clones of cells in response to the binding of an antigen. b) memory cells are vital to the primary immune response in that they immediately recognize pathogens even at the first encounter. c) memory cells are essentially effector cells that are short lived and attack antigens even without having a receptor specific to that antigen. d) it ensures that more lymphocytes with a receptor specific to a particular antigen will be present than in a host that had never encountered that pathogen.

Name the glands associated with human digestive system

Round seeds and yellow seed color are dominant to wrinkled seeds and green seed color. which punnett square represents the correct way to set up the cross rryy  ´  rryy?