December 8 - Happy Birthday, Jan Ingenhousz

Posted on December 8, 2021

Key Points

This is an update of my post published on December 8, 2010:

The Dutch scientist Jan Ingenhousz (1730-1799) discovered photosynthesis and also discovered that plants, like animals, have cellular respiration. Those are major, major discoveries—but not what he was best known for in his own lifetime. His claims to fame back then were:

(1) his successful inoculation of the royal Habsburg family of Austria – a kind of vaccination against the dreadful and deadly smallpox disease, and

(2) his appointment as the doctor of the Empress Maria Theresa.

Ingenhousz did a lot of work in biology and chemistry in at least six different European countries and corresponded many times with an important American, Benjamin Franklin.

Photosynthesis is the process by which plants use the energy in sunlight to convert carbon dioxide and water into sugars and oxygen. In other words, it is the process by which plants makes their own food!

Actually, plants don’t just make their own food—the photosynthesis by plants, some bacteria, and algae creates the basis of almost all food chains and therefore form the foundation of almost all life on earth—providing both food and oxygen for animals.

Check out to Peter Weatherall’s song about photosynthesis.

Photosynthesis starts in a plant cell’s chloroplasts. The green pigment chlorophyll is crucial to most photosynthesis.

Cellular respiration is pretty much the opposite of photosynthesis. It is the process by which plant and animal cells break down food (such as sugars) in order to obtain energy. The process requires oxygen.