Types of Photosynthesis in Plants: C3, C4, and CAM

We learned about photosynthesis over in the biochemistry series. But now that we are taking a closer look at plants, we need to learn about the different types of photosynthesis that exist within the plant kingdom. The version we learned already is found in C3 plants, and it is the most common type, but we also have to learn about C4 plants and CAM plants. These plants have evolved slightly different pathways in order to respond to environmental pressures. Let's see how this works now!

Script by Ryan Helcoski

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[maryamshariif]

Hello professor dave I am from Somalia And I have been watching you two years ago and i have benefited a lot from you thank you

[u.Luyanda_voerh]

Thumbs up if you are watching this before writing Biology test.

[sowmyarampoore]

That’s really cool professor. I am sitting for most toughest competitive exams in India and your videos are making my exam preparation easier. Thank you for your effort 👍🏻

[robfreiman]

Thank you Professor Dave! Just the video I needed! As always, very well done!

[nitin]

*I learnt all the three processes in just one video. Thanks*

[markdelaney]

I've learnt alot from dave over the years 👍

[blackbeard]

My first interaction with this topic was a 2nd year university assignment that asked to explain Kranz anatomy.

[MultiRedhammer]

The resulting 4 carbon compound? How is malate formed in the mesophyll cells from OAA??

[chrisdavidson]

He knows a lot about the science stuff. 👏🏽

[charlesjmouse]

I am continually amazed by the breadth of subject Prof Dave does videos on.

Rubisco is such an interesting enzyme. It's just about the most common enzyme you'll find in any plant cell, is incredibly slow by enzyme standards, and doesn't much care what direction it catalyses. Yet it's one of the most ancient and highly conserved enzymes in existence. What's been driving that 'lack' of evolution for billions of years when one would expect plants would really 'like' something better?
My best guess is it initially evolved to 'soak up' O2 when all life 'regarded' oxygen as a poison. For such a purpose you want:
-a lot of it to 'catch' every oxygen molecule as soon as possible
-so it didn't need to be efficient
-it did need to work so once functional there would be huge evolutionary pressure not to 'experiment'.
Some life discovered photosynthesis and Rubisco turned out to be useful for that as it would run backwards. Great, but now you need even more of it because 'whoops, there's even more of that nasty oxygen about!' So the pressure not to mess with a functional solution gets even bigger.
Finally you get some cells discovering the trick of aerobic respiration and so a poison becomes useful, when its not being poisonous. Before you know it you've got eukaryotes; the aerobic heterotrophs don't need Rubisco any more and ditch it, but the autotrophs are stuck with it warts and all.
It's a nice story, I'm afraid I'm not knowledgeable enough on the subject to know if it might be true.

[allianmariena-ong]

I don't understand how to calculate this problem.

Consider the fixation of carbon dioxide leading to the production of an amylose chain 30 glucose sub units long. Calculate the following: (a) the number of CO2 molecules fixed; (b) the number of ATP molecules consumed; (c) the number of NADPH molecules oxidized.?

[somyaagarwal]

your video helped me gain 6 free marks in my endsem exams thank you so much.

[ultrapromax]

I am form india and subscribe you.
Thanku so much professor Dave

[kitthecat]

professor dave always comes in clutch the night before an exam. thank you!! <3

[TheFarmacySeedsNetwork]

Really well explained my friend! I'll be linking to this video!

[abdullahbutt]

Loved ❤️ from Islamic Republic of Pakistan 🇵🇰 may Almighty Allah bless you

[ezudinezere]

Tnx Dave one day I will pay your gratitude

[vtygrhe]

No shit guys, he knows alot about the science stuff (unlike those flat earthers out there)

[FreemanVashier]

For the legal states, you can add Mj as a C3 plant

[THIS---GUY]

Dave this has nothing to do with this video. I just watched your discussion with Jesse Lee Peterson and had a good laugh. Hyperbole vs logic at its finest.

Thanks for your awesome channel, whether educational or educational

I rest my case