Photosynthesis

These processes are also the opposite in terms of inputs and outputs.

Photosynthesis uses energy to convert CO2 and water into sugar and oxygen.

And then cellular respiration converts sugar and oxygen into CO2 and water, plus energy.

Life is wildly symmetrical sometimes.

through living things, from photons of sunlight into physical movement.

But let's get microscopic.

Photosynthesis happens inside cells.

Even more specifically, it happens inside little structures called organelles within those cells.

And the oxidized organic matter comes up as CO2 and it goes in through the leaf.

That's called photosynthesis.

and the swapping of CO2 for oxygen.

Don't think I should be rather cynical about that.

You can rest knowing that the universe is carrying you forward.

Photosynthesis, the process by which plants convert sunlight into chemical energy, is one of the most important biochemical processes on Earth.

It requires only sunlight, water, carbon dioxide, and a few other elements to create sugar and oxygen.

This simple process, performed by plants and countless microscopic organisms, is the foundation of almost all life on Earth.

Strapped to his chest in a baby carrier sat his little brother, maybe six, holding flashcards in his tiny fists.

The kid blinked at the staring class and whispered, "Photosynthesis." Mr.

Howard crouched down, looked at the boy, then back at Doug.

"Getting your little brother to read the answers to you under a trench coat is a lot of effort to raise your grade.

Yes, that Calvin Cycle.

Photosynthesis is basically respiration in reverse, and we've already covered respiration, so maybe you should just go watch that video backwards.

or you could keep watching this one.

Either way, I've already talked about what photosynthesis needs in order to work water, carbon dioxide, and sunlight.

What was feeding all of this life? Every ecosystem known to science before 1977 was ultimately powered by the sun.

Photosynthesis, the conversion of sunlight into chemical energy by plants, algae and cyanobacteria was the foundation of every food web on earth.

herbivores ate the photosynthesizers, carnivores ate the herbivores, decomposers broke down the dead.

But at every level, the energy that drove the system came originally from sunlight hitting the surface of the planet.

The discovery of chemosynthetic ecosystems opened an alternative possibility that life might have originated not at the surface, not in the light, but in the deep ocean, at hydrothermal vents, where the chemical energy and mineral-rich fluids provided all the raw materials necessary for the assembly of complex organic molecules.

The deep-hot biosphere hypothesis Variations of which have been proposed by multiple researchers since the 1980s suggest that the first living organisms on Earth may have been chemosynthetic, not photosynthetic.

Photosynthesis, in this view, was a later evolutionary innovation.

an adaptation that allowed organisms to exploit a new energy source, sunlight, after life had already established itself in the chemical darkness of the deep ocean.

This cloud of dust and aerosols would rapidly engulf the stratosphere, plunging the Earth into a darkness so severe that global average temperatures would drop precipitously.

Photosynthesis, the basis of nearly all modern food webs, would cease entirely.

Within months, this darkness, combined with widespread famine and climatic failure, would guarantee the collapse of terrestrial and marine ecosystems, representing an insurmountable crisis for human civilization.

Let's face it, large celestial impacts are going to happen eventually.

And this is sort of in that concern area.

All food chains, of course, start with photosynthesis, which depends on light.

Photosynthesis depends on sunlight.

Now, I know you can get vertical farms where you can have artificial light, which can be very efficient.

This

I'm confused.

I genuinely don't get it.

Photosynthesis puts oxygen into the atmosphere as well, which of course we like.