<< Chapter 1: Photosynthesis, fat & cow pee << >>Chapter 3: Fancy words, ruling the world, superheroes>>
When you don’t understand, and aren’t in the mood to understand
Hello, my Alien friends, how are things? Your science teacher called you a potato in class today? Because you “just sit there like a potato, not interested in anything, not learning anything”? Well, I’m sure that like most teenagers, you have a lot on your mind, and you’ll have far more interesting things to think about than photosynthesis.
Never underestimate potatoes
Perhaps it was a compliment. Well, it could be a compliment because potatoes are very interesting. Potatoes changed the course of human history. We Europeans discovered potatoes in South America about 500 years ago, but we didn’t start eating them until about 200 years ago, at the end of the 1700s. Perhaps when we figured out that they taste better and aren’t poisonous if you cook them. Potatoes are easy to grow, and very nutritious – they give us lots of energy. Around 200 years ago, at the beginning of the period in history we call the Industrial Revolution, poor people around Europe suddenly had enough to eat for the first time. The Industrial Revolution was when we finally got around to inventing the things that make our lives comfortable today, like electricity, trains, lightbulbs, central heating, factories, vaccinations, photography, the telephone, the television, cars and aeroplanes.
How the potato changed the world
Until about 200 years ago, nearly everyone’s job was to grow food. This was a hard and risky job because in a year with bad weather, crops like wheat, fruit and vegetables could fail, and this happened quite frequently. However, potatoes grow underground, unlike crops like wheat or beans, so they’re protected from storms and droughts. So, until people started growing potatoes, they often didn’t have enough to eat.
When people started growing potatoes, more food meant more babies, which meant more workers to work in the new factories, which produced things like newspapers, weapons and cotton fabric for clothes. More babies also meant more soldiers, to fight in huge, new world wars. You just never know what effect innovations like potatoes will have on our lives.
Some tricks to make school easier: big ideas
Ok, your teacher calling you a potato probably wasn’t a compliment. School can be a tough place. What can we do to make school better for you? I mean, you have to go to school five days a week. That’s a long time to NOT be having a good time. What if you could learn a few tricks to make school easier?
There are a few big ideas that will help you make sense of the world you’ve landed in, which we’ll be looking at. A big idea is something that will help you make sense of things all your life, and can be anything: a good question, like “Who cares about photosynthesis?”, or a study tip, like looking at simple information for kids on the internet, or knowing about a period of great change in history, like the Industrial Revolution.
Learn to learn, because you’ll have to do it your whole life
For example, a way to understand the point of whatever scientific discovery you’re studying, is to ask, “What difference did it make?” “What was the world like before and after it?” I don’t know about you, but when I’m learning about something, I can’t just learn a list of facts. I need it to make sense to me.
Well, of course I still have to learn things. There are loads of things I don’t know, even at my age. Including things I should have learned at school, but was too busy paying attention to more interesting things.
What difference did photosynthesis make?
So, what difference did photosynthesis make to the world? Well, when I was finding out about potatoes, I asked the internet “How many more people are there on earth now, compared to 200 years ago?” This was when people started eating potatoes. It turns out there are 7 TIMES more people on earth now than there were at the beginning of the 1800’s. At the end of the 1700s there were a billion people on the earth and now there are over seven billion!!!
But then I clicked on images and found some graphs that showed that the earth’s population started growing very, very fast only about fifty years ago, and it has been growing very fast ever since. So, I asked the internet a few more questions and found out that although Mr. Ingenhousz, the scientist who discovered photosynthesis, worked out about 200 years ago that plants need sunlight to grow and produce oxygen, we didn’t figure out how to turn this discovery into ways of growing more food more quickly until the middle of the last century. By the way, it’s normal for it to take centuries to turn a scientific discovery into something useful.
You don’t get how this is going to help you learn about the vascular system of plants, about xylem and phloem?
Comparing things we don’t understand with things we do understand
Ok, let’s see if we can understand photosynthesis and plant anatomy by comparing this with something similar but that’s easier to understand. Comparing things, or finding analogies, is another big idea, by the way. Let’s look at how our human and alien bodies work.
Our hearts pump blood around our bodies through blood vessels, a lot of little tubes. Actually, our homes use a similar system. In our homes, we have pipes and wires that bring stuff to our houses, like water, gas and electricity, and pipes that take what we don’t want out of the house, like everything that goes into our toilet, or down the plug-hole when we wash things.
How we transport useful stuff to where we need it
So, we, like plants and houses, have systems for transporting useful stuff to where we need it in our bodies. We have blood and blood vessels, which are our vascular system. Our vascular system carries the nutrients, the things we need for our bodies to grow that we get from food, from our digestive system, to where we need it in our bodies for energy or energy-storage, or to our waste-disposal system, where we turn it into solid and liquid emissions and get rid of them. Our vascular system also moves the oxygen we breathe into our lungs around our bodies, which we need for our cells to turn the sugars and fats we get from our food into energy.
Humans and aliens have vascular systems. Houses and buildings have things like vascular systems, it’s called plumbing for everything to do with liquids, and wiring for electrical systems.
Plants pump stuff around themselves through pipes as well
Anyway, plants have vascular systems too: one set of tubes called xylem, like straws that suck up water and minerals from the roots to the leaves, where photosynthesis happens. And phloem, another set of tubes to move the nutrients produced by photosynthesis, like glucose and proteins to the growing parts of the plant, where it makes new leaves and other things like flowers or potatoes or strawberries. See? Sometimes if you compare new things with familiar things they become simple.
Normal vs. fancy words
Why do they have to use such complicated words, that you’ll never remember or use? Good question. When we speak there are two kinds of words we can use: normal, everyday words and fancy words, like photosynthesis, vascular system, xylem and phloem. We use these words to talk about ideas from biology, geography, history, literature – and all the other school subjects. Most of the fancy words we use, in Europe at least, are from two dead languages: Latin, which we haven’t spoken for at least 500 years, and Ancient Greek, which we haven’t spoken for almost 1,000 years.
Why? Well, people spoke these languages in Ancient Greece and Ancient Rome which are two very important historical periods on Earth, at least if you’re European, and these are two more big ideas that will help you make sense of this world. We’ll be talking about Ancient Greece and Ancient Rome a lot.
Right, your antennae are starting to droop – you need to go and recharge your batteries – time to go and put some fuel in your bodies.