Organization Of Multicellular Organisms Video

The body has a number of systems that protect against infection.

B cell, lymphatic tissue, lymphatic system, lymph node

lymphatic tissue, B cell, lymph node, lymphatic system

B cell, lymphatic tissue, lymph node, lymphatic system

Organ systems, such as the excretory and nervous systems, can each carry out all of the functions necessary for the organism's survival.

Organ systems, such as the respiratory and immune systems, carry out unique functions independently of one another, allowing the organism to carry out all of life's processes at the same time.

Organ systems, such as the circulatory and digestive systems, have unique roles but interact in order to carry out the functions necessary for life.

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Multicellular organisms contain worlds within worlds—each system is both made up of smaller systems and is part of larger systems.