Depolarization and repolarization are part of the action potential.
C. Action potential
Explanation:
Immunity is the ability of an animal to resist infection.
There are two types of immunity in the body; INNATE OR INHERITED IMMUNITY AND ACQUIRED IMMUNITY. Inherited immunity it is the type of immunity that one is born with. It is passed from parent to offspring.
Acquired immunity is immunity to particular infections that is not inherited but has developed in the animal's life as it interacts with its environment. Acquired immunity can develop naturally in which case it is called NATURAL ACQUIRED IMMUNITY OR ARTIFICALLY.
ACTIVE IMMUNITY is the form of acquired immunity in which the body produces its OWN antibodies against infections. While PASSIVE IMMUNITY is the form of acquired immunity in which an individual is PROTECTED AGAINST INFECTION BY RECEIVING ANTIBODIES.
NATURAL ACQUIRED IMMUNITY
when attacked by the same pathogens again, they don't became seriously ill. this is because memory cells are able to recognise the antigens and stimulate the immune system to produce antibodies against the pathogens. This is known as NATURAL ACTIVE ACQUIRED IMMUNITY. It develops when one recovers from an infection.
During pregnancy, the mother passes antibodies across the placenta to the foetus. At birth the baby gets antibodies from the mother through breast milk. This is natural passive acquired immunity.
<span>a. Fish have a single central heart; earthworms have several hearts.
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Multi cellular organisms are made up of billions of cells each specialized to a unique role and these cells are organized into structural and functional units such as tissues and organs.
For each cell and organ to function optimally, it requires oxygen and nutrients and needs carbon dioxide and metabolic waste taken away in a continuous, never ending process.
<span>A mechanism is needed to accomplish the important function of transporting the relevant materials to and from the cell. The circulatory system fits this bill splendidly. It is a specialized organ system which allows blood and lymph to flow through the entire body carrying nutrients such as glucose, amino acids and electrolytes as well as oxygen to each cell, at the same time carting away carbon dioxide and all sorts of metabolic waste over to excretory organs to be expelled from the body.
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Answer:
Nutrients makes the most sense.
The correct answer is A. grass
