Students in a science class learn that groundwater is an important source of drinking water for many communities. They construct a model to study how leaking chemicals from a landfill can affect groundwater. What is the most effective way for the students to see how leaking chemicals from a landfill can enter a well?

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.

What are they five steps of cloning?

This is a situation in which genes are attached to an organism's sex chromosomes; the sex of an organism influences the expression of a gene.