Because an antibody is "made" relative to the antigen, but kept at low levels when you are exposed the first time ("primary immune response"). The second time you're exposed to the same antigen, memory cells recognize it and the body produces a high level of antibodies, and the level of antibodies usually remains higher for a longer time ("secondary immune response"). This is your basic immune response (primary and secondary).
This explains exactly why vaccines are effective to extremely effective.
In general, the function of the excretory system is, removal of nitrogen waste products from the bloodstream and transport out of the body through urine. It maintains the balance of fluids and electrolytes, control of red blood cells, regulation of blood pressure and also the formation of red bone marrow.
In humans, the excretory system is responsible for removing waste from the body. Metabolic waste is being removed from the blood and an appropriate amount of water nutrients and water and salt are being retained.
In frogs, the excretory system consists of a pair of ureters, kidney pairs, cloaca, and urinary bladder. Frogs take in liquid waste from kidney which removes wastes and then the extra water becomes urine which then it is collected in the urinary bladder through ureters.
The urinary bladder is present in ventral to return then both open into the cloaca.
Your answer is going to be B
Asystole is defined as a cardiac arrest rhythm in which there is no discernible electrical activity on the ECG monitor. Asystole is sometimes referred to as a “flat line.” Confirmation that a “flat line” is truly asystole is an important step in the ACLS protocol.
