How do plants know when to “wake up”?

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Like how do they know to start germinating? Especially ones that have to survive extreme environments for years and years. Doesn’t it take energy to keep sensing those conditions? Couldn’t those conditions destroy their sensors?

In: Biology

2 Answers

Anonymous 0 Comments

Each plant has a set of requirements before germination. Some (most?) require a certain ground temperature. Many require a certian amount of time being frozen before they germinate. I have heard of an evergreen tree that requires their seed to burn before they germinate (the fire clears debris and gives the saplings room to grow)

It isnt so much that the plant has sensors, more like the plant needs certian criteria met. And the seed has some oil in it, making it less likely to freeze or dry up.

Anonymous 0 Comments

Enzymes.

If you remember from high school biology, enzymes are usually explained as “biological catalysts”, but it’s a vague description that didn’t make much sense to me so I’ll explain it in another way.

A large part of what makes up living organisms are things called proteins. Proteins are made up of Amino Acids. Think of Amino Acids like lego blocks. You have things in your body that are made up of proteins such as your hair and nails. They are all made up by combining different Amino Acids, just like how you would make a house out of different lego blocks.

Now, there are proteins that don’t just stand around. There are proteins which actually help in speeding up chemical reactions. Imagine for example, a robot made up of lego blocks. This robot’s function is to stack more lego blocks in order to build something more faster and more efficiently compared to a human, but don’t forget that the robot itself is made up of lego as well.

The robot can be thought of as the enzyme. Enzymes are essentially useful proteins which help in building other proteins, or perform certain chemical reactions.

Now, the thing about enzymes (and proteins in general) is that they’re sensitive to temperature and pH (acidity). So there is an “optimal” temperature and pH for enzymes to be able to perform their task, but other than that the enzymes will be inactive or even broken. Think of it as the lego robot requiring the correct batteries to function. If you give it AAA batteries, the robot will be activated. But if you give it the wrong type of batteries, it will not be able to function.

Finally, this brings us back to plants and seeds. Essentially, the seeds contain special enzymes that can only be activated when certain conditions are met: right temperature, right pH, right amount of water, etc. So when it is in the soil and the conditions are met, the enzymes get activated and the whole cellular machinery of the plant gets to work.

I hope this helps.