Answer:
Explanation:
The cardiac conduction system are specialized cardiac muscle cell that are located in the walls of the heart and sends signals to the heart muscle. These signals cause the heart to contract. The main components of this system are AV node, bundle of His, SA node, bundle branches, and the Purkinje fibers.
But it was not until 1928 that penicillin, the first true antibiotic, was discovered by Alexander Fleming, Professor of Bacteriology at St. Mary's Hospital in London.
Answer: Active transport
Explanation: <u>Active transport is one way in which organisms maintain homeostasis.</u> For example, an amoeba uses phagocytosis to<u> take in food</u>. The amoeba needs the food for <u>energy and growth</u>.
