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Course: Middle school biology > Unit 3
Lesson 1: Photosynthesis in organismsPhotosynthesis in organisms
Plants, algae (including phytoplankton), and many microorganisms use the energy from light to make sugars (food) from carbon dioxide from the atmosphere and water through the process of photosynthesis, which also releases oxygen. These sugars can be used immediately or stored for growth or later use. Created by Khan Academy.
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- Planty the Plant, ah yes very original(34 votes)
- right his/her name is so stodanary such an amazing am I right or am I right(0 votes)
- How does cell and molecule differ?
Chloroplast vs. Chlorophyll(7 votes)- Here's what I found on Google: "Further, chlorophyll is food producers of the cell which are present in green plants, found inside the chloroplast. On the other hand, the chloroplast is a unique organelle present in all green plants and is the site of photosynthesis."
In simpler words, chlorophyll is the chemical that helps with photosynthesis, and the chloroplast is the organelle. Think of it like the chlorophyll being the chemical and the chloroplast being the science lab.(17 votes)
- "planty" hmm, creative.(15 votes)
- Fun Fact: The Ocean produces most of our o2.(16 votes)
- exactly thats actually a good respons or a fun fact(0 votes)
- who discovered Photosynthesis(9 votes)
- According to Google's Answer to your question, Photosynthesis was partially discovered in the 1600's by Jan Baptista van Helmont, a Belgian chemist, physiologist and physician. Helmont performed a 5-year experiment involving a willow tree which he planted in a pot with soil and placed in a controlled environment.(12 votes)
- who wants to listen to the video and walk around(10 votes)
- She’s talking to a digital plant. I think she’s crazy.(5 votes)
- She isn't necessarily crazy just because she's talking to a digital plant. She just using it as an example to help us learn.(6 votes)
- *What is the difference between Cells and Molecules?*(5 votes)
- Cells are made of proteins, which are a type of molecule, and water, which is another molecule, and other things which are all made of molecules. Molecules are the collections of atoms, that is Water is composed of Oxygen and Hydrogen atoms, Proteins are made of Carbon, Hydrogen, Oxygen, and different components.(4 votes)
- A plant named planty, why am I not surprised(6 votes)
- What about plants that aren’t green? Do they photosynthesis?(4 votes)
- The answer is yes. Other photopigments can also utilize photosynthesis to convert the sun's energy. Plants that have purplish-red leaves, like Japanese maples, use the photopigments that are available in their leaves for the process of plant photosynthesis. In fact, even plants that are green have these other pigments.(4 votes)
Video transcript
- [Narrator] Hey, I'm gonna let you in on a little secret of mine. I love gardening. In fact, I have a huge garden with apples, blueberries, pumpkins, and tomatoes. I give my plants micronutrients,
and maybe some fertilizer. But I don't give them food in the same way that I would give my dog who
eats multiple times a day. With plants, I just put them in the soil, water them regularly, and watch them grow. How do they do it? Well, they use a process
called photosynthesis. Photosynthesis is a
scientific term to describe how certain living things
use energy from sunlight to live and grow. Many different kinds of plants, algae, and various single-celled
organisms are able to carry out this amazing process. Today, let's describe
photosynthesis using tomatoes. So here you see a young tomato plant, similar to the ones I
have in my own garden. Let's name it Planty. First, let's start off by looking at Planty's
immediate surroundings. The soil Planty is
growing in contains water and the air surrounding
Planty contains molecules of carbon dioxide. These two compounds are the
starting materials or inputs that Planty needs in order
to carry out photosynthesis. Now, let's take a look
at the weather forecast. Well, it looks like it's
gonna be a sunny day today. So when the sun shines on the earth, it sends out energy in the form of light. This energy is essential for Planty to be able to carry out photosynthesis. Next, let's take a closer look at Planty, because Planty's cells are
hiding a secret of their own. Inside Planty's cells are
microscopic structures that help Planty carry out photosynthesis. These structures are called chloroplasts. Chloroplasts contain
green pigment molecules called chlorophyll. It is actually within these molecules that the sun's energy is captured for use during photosynthesis. Interestingly, chlorophyll
is where leaves get their green color. To help you remember, think
of chlorophyll like this: chloro means green and phyll means leaf. So when you put them
together, you get green leaf. Okay, so now we know that
carbon dioxide, water, and sunlight are required
for photosynthesis to occur. And we know that in plants like Planty, photosynthesis happens in the chloroplast with the help of chlorophyll. Next, let's take a look at what happens during the process of
photosynthesis itself. When the sunlight reaches
Planty's chloroplast, its energy is used to rearrange the atoms in the carbon dioxide and water molecules through a series of chemical reactions. The outputs of these reactions are oxygen molecules and sugars. These sugars are vital
to Planty's survival because they are used as a
source of chemical energy that helps Planty live and grow. In other words, they're Planty's food. Planty can do a few things with the sugars made
during photosynthesis. It can break the sugars down to get usable energy right away, or it can store the sugar
molecules for later use. If Planty stores the sugar molecules, it can then use them as a
source of energy in the future. This means that Planty can grow even when the sun isn't shining. Planty can also use the sugar molecules to build larger molecules
such as cellulose that make up the structure
of Planty itself. In this way, Planty can
grow bigger and bigger with very little help from me; all thanks to the process
of photosynthesis. Planty's other output, oxygen, is released into the atmosphere. This is really cool because
it provides organisms in the ecosystem,
including us, with oxygen. So thanks Planty and other
photosynthetic organisms for giving us the oxygen
we need to breathe. And that, my friends, is photosynthesis. So next time you're in a garden, I want you to think about this. All the plant structures you
can see, such as stems, leaves, and even the fruits and
vegetables that we eat are made up mostly of the
atoms that were once a part of the starting materials
of photosynthesis. With the help of a little sunlight, the plants made their
own food and grew bigger, taking CO2 out of the atmosphere and releasing oxygen back
in for us to breathe. And on that note, I
think I should go outside and give my own garden some water. See you later.