B- Electron transport chain
Two or more organs form together make organ systems.
<u>Explanation:</u>
The basic unit of living organisms is the cell. Multiple cells makes up tissues and tissues make up organs. Two or more organs make up the organ system.
Human body has several organ systems. The organs that make up an organ system can be internal as well as external. Respiratory system is made up of organs like lungs, nose, pharynx, trachea, diaphragm etc. digestive system is made with organs like liver, small intestine, stomach, mouth , large intestine, pancreas etc.
Answer:Physical systems differ from social systems because a physical system refers to systems that rely on a group of physical parts to perform a function. Examples of a physical systems are solar systems or even an animals digestive system. Social systems are systems like an ant colony, wolf pack, or a town.
Explanation:
Enclosed within the nucleolus of the cell.