Almost all animal species—including humans—have blood cells, but between different species our blood tells different stories. The lineage and components of blood cells vary widely, and this variety is ...

Lipids are fatty molecules that play critical roles in cell function, including membrane structure, energy storage and nutrient absorption. Most lipids are made in a cell organelle called the ...

Life’s fundamental structure is the cell, and so the main things that a cell does — processing biomolecules, growing, replicating its genetic material and producing a new body — are considered ...