The correct answer is the organ.
The multicellular species are formed of various parts, which are required for survival. These parts are differentiated into the levels of the organization. There are five different levels, which are named as cells, tissue, organs, organ systems, and organisms.
When two or more layers of tissue function together, they produce an organ. All the animals comprise vital organs, without which they cannot survive. These include the kidneys, liver, lungs, brain, and heart.
Answer:
Start from the bottom and go up.
During the carbon cycle, animals and plants add carbon dioxide to the atmosphere through cellular respiration, and plants remove carbon dioxide through photosynthesis. The burning of fossil fuels releases more carbon dioxide into the atmosphere, contributing to global warming.
There are several ways;
The Skeletal system protects for example the heart and several aspects of large vasculature. The skeleton also has the means to produce blood cells in the marrow of some of the bones.
