Hey there! Imagine if life was like a cooking show. Today, we’re diving into the “primordial kitchen” to explore what makes up life itself. Just like a recipe, life has its own special ingredients, and we’re here to find out what they are!
First things first, you can’t have life without water. It’s like the main ingredient in our recipe. Then, we add a sprinkle of carbon, a dash of nitrogen, and a pinch of salt. Don’t forget calcium for strong bones and a touch of phosphorus. These are just a few of the key elements that make up living things.
But wait, there’s more! Life also needs trace elements, which are like the spices that add flavor to our dish. Mix it all together, and you’ve got the basic building blocks of life.
Now, if only creating life was as easy as baking a cake! In reality, it’s much more complex. Living things don’t come with ingredient labels like the ones you see on food packages. But if they did, you’d find a long list of chemicals with funny names. These are the molecules that make us who we are, help us move, store energy, and even let us think and learn.
In fact, if you listed all the nucleic acids, lipids, proteins, carbohydrates, vitamins, and other essential components, you’d have a cookbook full of ingredients just for you!
Long ago, people thought everything was made of just four elements: Earth, water, fire, and air. Today, we know it’s a bit more complicated. Living things are made of cells, which are made of molecules, and those molecules are made of atoms.
Interestingly, 97% of the mass of all living things is made up of just four elements: carbon, hydrogen, nitrogen, and oxygen. For example, an average person has about 16 kg of carbon, enough nitrogen to fill 400 liters of urine, and enough oxygen to fill the volume of six elephants!
Out of the 98 naturally occurring elements, only about 30 are essential for life on Earth. So why is carbon so important? Carbon’s special chemistry allows it to form a variety of shapes and bond with other elements like nitrogen, sulfur, and phosphorus. This versatility is why life on Earth is “carbon-based.”
While silicon is more abundant in Earth’s crust, it doesn’t have the same bonding capabilities as carbon. That’s why we’re not “silicon-based” life forms. Carbon’s ability to create complex structures is what makes life so diverse.
Life began in ancient seas, which is why water is a major part of our bodies. When you’re born, you’re more than 75% water! As you grow older, you dry out a bit, but water remains crucial. It combines with ions like potassium, sodium, and chloride to keep our cells functioning and send signals through our nervous system.
Our bodies also contain trace elements like iron, magnesium, cobalt, and copper. These elements play important roles in our health, even if they’re present in tiny amounts. Over time, we accumulate traces of elements from our diet and environment, leaving behind a unique chemical signature.
Did you know that if you collected all your toenails and hair, you could find a tiny amount of gold? It’s not much, but it shows how diverse our body’s elements are.
If you could separate all the elements in your body, they’d be worth around one to two thousand dollars. But of course, life is priceless! Remember, you’re more than just the sum of your parts. Stay curious and keep exploring the wonders of life!
Explore your surroundings and identify objects that contain the essential elements of life. Make a list of items and the elements they contain, such as carbon in a pencil or calcium in chalk. Share your findings with the class and discuss how these elements are important for life.
Imagine you are a chef creating a recipe for life. Write down the “ingredients” you would need, such as water, carbon, and nitrogen. Describe the role each ingredient plays in the “recipe” and why it’s essential for life. Present your recipe to the class and compare it with others.
Using craft materials, build a model of a cell, highlighting the key molecules like proteins, lipids, and carbohydrates. Label each part and explain its function in the cell. Display your model in the classroom and explain how these molecules contribute to life.
Learn about carbon’s bonding capabilities by using molecular model kits to create different carbon-based structures. Experiment with forming chains, rings, and complex shapes. Discuss why carbon’s versatility is crucial for the diversity of life on Earth.
Research one trace element found in the human body, such as iron or copper. Create a poster that explains its role, sources in the diet, and what happens if the body lacks this element. Present your findings to the class and learn about the importance of trace elements in health.
Sure! Here’s a sanitized version of the transcript:
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[MUSIC][APPLAUSE] Welcome to Ph. Deeelicious! I’m your host, Joe, and today in the primordial kitchen, we’re cooking up life. I’m hungry already, let’s get started! [APPLAUSE] You can’t have life without water. A touch of carbon! Mmm, nitrogen! A little salt of the Earth. Calcium, strong bones! Just a touch of phosphorus. That’s enough! What about all those trace elements? A little spice of life! Bam! Bam! BAM! BAM!! Let’s mix that all together… [MUSIC] Mmm, tangy! We’re gonna pour that into a baking dish and pop that baking dish into a 350-degree oven for about three and a half billion years. And here’s one we prepared earlier! [APPLAUSE]
That would be pretty cool, but cooking up life is a little more complicated than following a recipe. Living things don’t come with nice, convenient ingredient labels like the packages we buy at the store. But what if they did? Huh, I didn’t know that pineapples have 3-methylthio-prio-pria-pineapple-o-ate. Those chemicals have strange names, but they’re just the stuff of life, the molecules that build us, make us move, store energy and information, even the ones letting you watch and think about this video.
And that’s not even the whole list. If we add in all the nucleic acids, lipids, proteins, carbohydrates, and also all those minor players like vitamins and cofactors, things like… I’m not even gonna try that one. The point is, in the recipe for life, the ingredients list for you and me could fill a whole cookbook. But what if we put you in a molecular blender and converted all your complex chemicals into one human molecule?
This is what your chemical formula looked like at birth: Now, in ancient times, scholars believed everything in the universe was made of just four elements: Earth, water, fire, and air. Today we know it’s a little more complicated than that: living things are made up of cells, cells are made of molecules, and they’re made of even smaller atoms… BUT that old idea turns out to be sort of right. Altogether, 97% of the mass of all living matter is made of just four chemical elements. You’re no exception. An average-sized person has 16 kg of carbon inside them, more nitrogen than in 400 liters of urine. Converted to gas, you hold enough oxygen to fill the volume of 6 elephants, enough hydrogen to fill the volume of a blue whale.
Add in a few more elements, and that’s nearly ALL of what makes up nearly everything. Different organisms tweak the percentages a bit, like how our bones are full of calcium, or how plants use boron in their cell walls, but all in all, life seems to work a lot like a restaurant, crafting an infinite menu from the same handful of ingredients.
But this barely scratches the surface of the periodic table. Out of 98 naturally occurring elements, just over 30 of them are known to be essential to some form of life on Earth. Why so few? Because not all elements are created equal. There’s a reason we are “carbon-based life forms” and all of our living chemistry is “organic.”
Many creation stories say life was molded from clay, from the Earth itself, yet our planet doesn’t actually contain much carbon. But there IS another element in Earth’s crust a thousand times more abundant than carbon, and which, like carbon, has four outer electrons, and sits just below it on the periodic table.
Why aren’t we silicon-based? Carbon’s special chemistry lets it bond in a variety of different shapes, building on itself and other atoms, like nitrogen and sulfur and phosphorus, in long chains and branches, everything from DNA to amino acids to sugars to fats. Silicon can’t do that. Slap two oxygens on a carbon, and you get a gas that plants can eat. Combine two oxygens with silicon, and you get sand.
We’ve figured out other ways to put silicon to good use, but it’s carbon’s variety that led to the variety of life, and right now, there’s no reason to believe that life in other parts of the universe would be built on a different backbone. Rather than dirt, early life was born in ancient seas, which is why the hydrogen and oxygen from water dominate our ingredient list. When you’re born, you’re more than 75% liquid, but we all dry out as we get older. Muscle contains more water than fat, our skin is almost two-thirds liquid, even our bones are more than 30% wet stuff.
In our body, that water is combined with a mix of ions like potassium, sodium, and chloride, the salts that keep our cells from collapsing and send electrical signals through our nervous system. We are a salty sea, just like the sea we came from. As we age, changing through the years, our human chemical formula changes with us. Those rare elements at the bottom of our list, like the iron in our blood, the magnesium that surrounds our DNA, cobalt in vitamin B12, copper at work in our mitochondria, are joined by others that don’t seem to do anything at all.
The average adult contains detectable amounts of 60 elements, mostly just traces of our diet and environment that have built up over time, remnants of past experiences. In fact, if you cut off all your toenails and hair, you could even mine gold… not much, maybe a tiny nugget no bigger than a single grain of salt, worth about a tenth of a cent. But what about the rest of you? If you isolated all the elements that you’re made of into their pure form, well… you’d be dead. But if you did this to someone else, the ingredients for one life would fetch around one to two thousand dollars on the open market.
Of course, you can’t really do that, but it gives us another way to look at life: Everybody’s worth something, and thanks to inflation, you’ll be even more valuable tomorrow than you are today. You’re definitely more interesting than what’s on your label. Stay curious!
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Let me know if you need any further modifications!
Water – A transparent, tasteless, odorless, and nearly colorless chemical substance that is essential for the survival of most living organisms and is a major component of the Earth’s hydrosphere. – Water is vital for all known forms of life, and it makes up about 60% of the human body.
Carbon – A chemical element with the symbol C and atomic number 6, which is a fundamental building block of life and is found in all organic compounds. – Carbon is present in every living organism and is a key component of molecules like DNA and proteins.
Nitrogen – A chemical element with the symbol N and atomic number 7, which makes up about 78% of the Earth’s atmosphere and is essential for the formation of amino acids in living organisms. – Plants need nitrogen to grow, and they absorb it from the soil through their roots.
Calcium – A chemical element with the symbol Ca and atomic number 20, which is important for bone health and is found in many foods. – Calcium is crucial for the development of strong bones and teeth in humans and animals.
Phosphorus – A chemical element with the symbol P and atomic number 15, which is essential for the formation of DNA and RNA in living organisms. – Phosphorus is a key component of ATP, the energy molecule used by cells.
Molecules – Groups of two or more atoms bonded together, representing the smallest fundamental unit of a chemical compound that can take part in a chemical reaction. – Water molecules consist of two hydrogen atoms bonded to one oxygen atom.
Cells – The basic structural, functional, and biological units of all living organisms, often called the “building blocks of life.” – All living things are made up of cells, which carry out various functions necessary for life.
Elements – Pure chemical substances consisting of one type of atom, distinguished by its atomic number, which is the number of protons in its nucleus. – The periodic table organizes all known elements based on their properties.
Chemistry – The branch of science that studies the composition, structure, properties, and changes of matter. – Chemistry helps us understand how substances interact and change during chemical reactions.
Life – The condition that distinguishes living organisms from inorganic matter, characterized by growth, reproduction, and the ability to respond to stimuli. – Scientists study the chemistry of life to understand how living organisms function and evolve.
