Part E - In addition to natural factors, human activity can also alter ecosystems. Conduct research on a human activity that currently affects or can theoretically affect your chosen ecosystem. Use your food web model to explain how this change can affect the competition for food resources.​

Arrange these elements of the intrinsic conduction system in the order that a depolarizing impulse travels during a normal heartbeat. rank from first to last. do not overlap any tiles. view available hint(s) reset av nodeav bundleinternodal pathwaysbundle branchessa nodepurkinje fibers

Ihave no idea how to solve these. plus there's another question that is 2) a 10 kilogram meteorite is collected in space and brought back to earth. it is composed of 1.25 kg of uranium-238 and 8.75 kg of lead-206. how many u-238 half lives have passed? what is the approximate age of the meteorite?

Which of the following statements is correct in hour our immune system responds to a potential pathogen? a. the adapted immune system will call on the innate immune system to destroy the pathogen. b. b cells will start reading the antigen code immediately and call t cells to assist in destroying the pathogen. c. the skin will be the first line of defense, and then the many phagocytes in the bloodstream will attempt to consume the possible pathogen. d. the t-cells in the adapted immune systems are the first to recognize the pathogen vaccines are weakened forms of disease causing microorganisms, which are given to patients to prevent disease. after the vaccine is administered, the immune system responds by creating a(n) to recognize the a. antigen, antibody b. antibody, antigen c. antibody, antibiotic d. antibiotic, antibody