Keeping you fed
First off, if plants didn’t produce their own food, you wouldn’t have anything to eat — period. So you can thank the process of photosynthesis the next time you sit down to eat.Just consider a slice of cheese pizza: You use grains from wheat plants to make flour for the crust, fruits from tomato plants for the sauce, and milk from a cow to make the cheese. The cow is not a plant, but how does it make milk? With the food molecules it gets from eating plants, of course. Everything you eat, no matter how complicated, can be traced back to the food makers such as plants. Without the raw material they provide, nothing else could live on planet Earth.
Putting microbial enzymes to work
Microbes aren’t just for making foods; they have a wide variety of industrial applications too. Manufacturers put bacterial enzymes in laundry detergent to help break down greasy stains and in meat tenderizers to help break down proteins in meats. If you take vitamin C, chances are that vitamin was produced by a fungus. If you drink a protein shake regularly, the amino acids in that shake probably also came from bacteria. So you see, not all microbes are to be feared. Some of them actually improve your life by simplifying tasks and keeping you healthy.Designing genes
The food you eat could very likely contain genetically modified organisms (GMOs) — living things whose genes have been altered by scientists in order to give them useful traits. For example, crop plants may be engineered to better resist pests, and animals may be treated with hormones to increase their growth or milk production.Some people object to the idea of GMOs in their diets, but genetic modification of organisms has enabled some amazing health breakthroughs. If you know someone who takes insulin to treat diabetes, that insulin is made by bacteria that scientists engineered to contain the human gene for insulin.
Powering the planet
Although people are starting to turn to renewable sources of energy, most of the world still runs on fossil fuels such as oil and coal. The word fossil may give you a clue that these fuels are the remnants of living things from long ago. Way back in the Carboniferous period, about 350 million years ago, green algae, plants, and bacteria used photosynthesis to harvest energy from the sun and transform it into the chemical energy stored in their cells. When these living things died, they were deposited in such a way that their energy-rich remains converted into coal, natural gas, and oil.These ancient energy reserves powered the Industrial Revolution, allowing people to grow their cities and develop new technologies for transportation, manufacturing, and communication. Unfortunately, these advances came with a cost that wasn’t fully recognized until recently.
When people burn carbon-containing molecules from fossil fuels, they produce carbon dioxide as waste. And carbon dioxide is an important greenhouse gas, a gas that traps heat in our atmosphere. In part due to our use of fossil fuels, the Earth is warming, which is already affecting the survival and distribution of life on Earth. Plus, people are now facing the fact that our reserves of fossil fuels won’t last forever.
Maybe one solution to both of these problems lies in mimicking the green organisms that stockpiled this energy in the first place — people could act like plants and go solar!
Causing and treating infectious disease
Whenever you get sick from an infectious disease, such as a cold or strep throat, you’re dealing with the reproduction of an alien invader. Your immune system springs into action, activating the cells necessary to fight the invasion and keep the infectious virus or bacteria from replicating itself any further. Also, whenever you take an antibiotic, you’re taking a medicine made by an organism such as a fungus or a bacterium. And when you get a vaccine, you’re getting an injection of dead or weakened pathogens so that you can train your immune system to fight them should the real thing ever infect you.Staying alive
Scientists are working with cells, the smallest unit of life, to come up with new therapies to help people with organ failure and devastating injuries. Stem cells, which have the potential to become any kind of cell, have the most potential for this research. Scientists working on ways to coax cells to grow into new organs in the lab were recently able to get human cells to grow into an organized structure that looked like an immature heart and that started beating when they gave it some electricity.If scientists can perfect these techniques, they could someday grow organs for people from their own stem cells, which means the patient wouldn’t reject the transplant. In another amazing experiment, scientists injected stem cells into the spine of a young man who was completely paralyzed, enabling him to regain the use of his arms and hands.
Cells are the smallest living component of your body, and they can do amazing things. Every minute of every day, your cells are quietly working away, digesting your food, sending signals that control your responses, transporting oxygen around your body, contracting so you can move, and making all of your other bodily processes happen. If your cells weren’t functioning, your tissues, organs, and organ systems wouldn’t be either.
Providing you with clean water
You have wetlands to thank for the clean water you enjoy. Wetlands are areas that are saturated by water most of the time. They act like natural sponges, holding onto water and slowly filtering it around the plants that live there. As water slowly filters through wetlands, plants and microorganisms have time to absorb human wastes such as fertilizers and sewage, cleaning the water and making it safer for humans and other animals to consume.All life on Earth needs water — clean, fresh water — in order to be healthy, so wetlands are pretty important to your quality of life. Unfortunately, wetlands are under incredible pressure from development and oil exploration, and they’re disappearing at a rapid rate.
Another way living things help keep water clean is through sewage treatment. Bacteria break down the organic matter in sewage, helping to clean the water before it’s released back into the environment.
Changing physically and mentally
Chances are that at some point in your life you either were or will be “ruled” by your hormones. Case in point: You meet someone you’re attracted to, signals cause hormones to be released, and suddenly your conscious mind isn’t making all the decisions. If that example doesn’t convince you of the power of hormones, just think back to puberty. During that time, your body went through an incredible transformation based solely on the signals from these potent chemical messengers.Creating antibiotic-resistant bacteria
The populations of living things around us are constantly changing, or evolving, in response to the environment. We probably notice this most when the changes are a threat to our health and well-being. For example, most people today have heard stories about dangerous bacteria and viruses. This includes bacteria like MRSA (which stands for methicillin-resistant Staphylococcus aureus), which can’t be killed with most antibiotics. Where do antibiotic-resistant bacteria come from?The answer lies in the idea of natural selection, or survival of the fittest. Bacteria reproduce very quickly, and little changes in the traits of individuals occur with each generation so that even all the bacteria of one species aren’t the same as each other. When people use antibiotics, the susceptible bacteria die first, leaving behind the most resistant cells. These resistant cells multiply and take over the available space.
As this scenario repeats over time, populations of bacteria eventually become super-resistant to antibiotics, explaining why sometimes doctors don’t have the drugs to help people who are infected with an antibiotic-resistant bacteria For the first time in a long time, people can die from an infection simply because doctors can’t kill the bacteria.
Facing extinction
Perhaps you don’t think about extinction much, but it’s something worth being aware of. If you need an example, consider the case of polar bears. As global temperatures rise, the polar ice is melting, leaving polar bears with less and less habitat. Not quite so noticeable, but also endangered, are 1,900 other species of plants and animals.As humans convert more land and resources to their own uses, less and less habitat is available for the other organisms on Earth. Each species needs certain conditions and resources to thrive, and the sheer number of humans on Earth is threatening to overwhelm many ecosystems. That spells bad news for humans because we depend upon the health of ecosystems for our own survival.