4. Which is the best expression of how scientists think of cause and effect? Everything is totally random.
Things happen all the time for no reason
Everything happens for a reason
It's impossible to decide what causes most phenomena in the universe.

Which of the following best describes the purpose of technology?

What are the formed elements (cell or parts of cell) in blood and what are their functions ?

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.