There are many different things in the world around us; look around your room now, and you’ll find many examples. A book, maybe? A cat? A pencil? And we can separate all of these things into two categories – living and non-living things.
Good news means you’re a living thing if you’re reading this! (Unless you’re a ghost, we recommend you stop reading this page and go back to doing other ghostly things.)
But what are living things and non-living things? What makes us living and other items not so much? And what makes other things living, too, like plants and animals? After all, we’re all quite different.
Fear not. There are ways for us to tell the difference between what is a living thing and what isn’t. There are vital things living things do and non-living things that don’t. And scientists have come up with a list of characteristics that something must have for it to be seen as living. These things include being able to grow and reproduce. But, of course, some non-living things will be able to do some of these things, too – like a fire, which can expand and multiply. But a fire isn’t a living thing because it doesn’t have all the characteristics that a living thing must have.
And we also show these characteristics in different ways. A tree, for example, is very different from a dog (do you hear any trees woofing? Dogs growing leaves?), but they are still both living things because they satisfy the characteristics in different ways.
Keep reading to learn how living things grow!
What are living things and non-living things?
Living things have the same life cycle – birth, growth, reproduction, and death. However, living things don’t live forever and have a specific life span. Living things are made up of microscopic structures called cells, which go through cellular respiration, allowing them to take in energy and perform their functions.
Living things grow and move, though not always in the same way. Humans will move by walking, running, and all those things. But plants move too to reach sunlight. I’m not saying that you’ll see a plant pick up its plant pot and run a marathon anytime soon, but you will see a plant move toward the sun. Put one plant in a dark corner and one with a view of sunlight, and watch how they grow changes as they both try to reach the sunlight.
Living things also meet the following characteristics to be classed as living.
A living thing must be organized. To be organized, a living thing must have an orderly structure or organization. All living things are made up of one or more cells.
A living thing must be able to reproduce. By this, we mean that a living thing can create offspring, letting life continue by creating more living things. Humans do this by having children, and plants do this through both sexual and asexual reproduction. Through reproduction, parents can pass on genetic information to their offspring.
All living things grow. You’re a different size now than when you were born. That’s because you’re living! Other living things also grow, like plants, as they move through various stages of development.
All living things respond and adjust to their environment. For humans, this could mean our bodies changing their temperature. Like when it’s hot, our bodies sweat, and when it’s cold, our bodies shiver. And when we read fascinating teaching wikis like this one, we sit with big smiles!
Take in nutrients
Food, glorious food! All living things take in nutrients to survive, which, for us, means eating food. Cheeseburgers for everybody! (Just kidding.)
Plants take in nutrients through photosynthesis, where the chlorophyll in leaves soaks in the sunlight and turns it into energy. Not as tasty as cheeseburgers, but nutritious all the same.
Living things adapt to their environment, so they have a better chance at survival; this means that the way a living thing looks and behaves is suited to its environment to keep them living. For example, giraffes have long necks to eat tall trees. Or a polar bear, who lives where it’s freezing, has thick fur to keep warm.
Did you know it’s not just animals that adapt to survive, but plants too? Like, for example, the cactus. Because a cactus tends to live in a scorching desert with little water, they have long roots to collect water from a large area and a stem that can store water for a long time.
After taking in nutrients, all living things excrete waste; this means poo for us human folk.
How do living things grow and develop?
While they may often be confused as the same thing, growth and development are two different processes. On the one hand, growth is when organisms increase in size and mass. While development is when organisms completely transform in the process of evolution.
All living organisms must grow and develop throughout the aging process. Humans, for instance, begin life as babies, at which time we have all of the same key features as an adult, such as eyes, ears, feet, hands, a heart, etc. However, at this point, we are tiny. As we age, we grow in size and mass and become adults. All the while, we maintain the same features that we were born with. This process is called growth.
Human beings also go through a process of development, but this happens before we are born. In the womb, we start as single-cell organisms and then completely transform into a zygote before changing again into a fetus and, finally, into a baby.
The question of ‘how do living things grow and develop?’ differs from organism to organism. The processes are much more dramatic for some organisms, while it is more minimal for others.
Plants, for instance, can start life as tiny seeds and grow into large trees as they age. However, one common feature connects all living things in their growth and development. They all grow and develop to look like their parent species.
Repair is a big part of how living things grow. There is a certain amount of wear and tear that occurs throughout the aging process for a cell. Throughout this time, the cell may suffer injury or bruises, and their ability to carry out different life functions weakens. In this case, cells repair themselves by growing new cells in Mitosis.
The seven functions of living things
Seven essential functions are necessary for life. As such, every living thing must carry out these functions to survive.
All living things must be able to move in some way without needing external help. The type of movement can vary from organism to organism. For some organisms, this movement will look like an internal flow of material or an external movement of either part of the organism or the organism as a whole.
Living organisms must have a certain degree of sensitivity to respond to what is happening around them. For instance, green plants sense the Sun and grow towards it to get nutrients.
Another requirement for all living organisms is respiration, the chemical process by which organic compounds release energy. There are two types of respiration: aerobic, which requires oxygen and releases lots of energy, and anaerobic, which doesn’t require oxygen but releases much less energy.
Cellular respiration releases energy stored in food molecules, and all living things must be capable of it.
Energy is vital for any living thing to survive, and they get energy from nutrients from food. The source of nutrition will be different depending on the organism. Green plants, algae, and certain archaea and bacteria can make their food from water and carbon dioxide through a process known as photosynthesis. Legumes, on the other hand, make proteins by taking in nitrogen, which comes from the bacteria that live in the plant’s roots. Moreover, animals, fungi, protozoa, and many archaea and bacteria cannot create their food, so they have to find it from an external source. There are many ways they can do this, depending on the physical makeup and capability of the organism. Animals, for instance, can hunt and feed off of each other.
As living things get older, they grow. Although lifeless or inanimate things can grow, they do so differently from living organisms. Living things grow by creating new parts and materials and changing the old ones; this is why, as humans grow, we get new teeth, etc., and the shape and proportions of our bodies changes. Healing is also a part of the growth of living things. For instance, our bodies grow new skin when we cut ourselves.
Reproduction is an essential function of living things. Without it, more living things would not be able to be created. Like many other processes mentioned in this list, reproduction will look different depending on the organism. However, the result is always the same: a new living organism is created.
The last of the seven essential functions is excretion. Excretion is how living things create and dispose of waste products. Most of this waste derives from food, while the rest comes from movement, growth, and other living functions.
An easy way to remember these functions is with the acronym: MRS GREN, which stands for Movement, Respiration, Sensitivity, Growth, Reproduction, Excretion, and Nutrition.
There are also lots of non-living things. Your toothbrush in the bathroom? The dog bowl in your kitchen? What computer screen you’re reading this on? They’re all non-living things.
They’re not living things, meaning they don’t possess life. They don’t meet all of the above characteristics like we do. They don’t have a lifespan or need food and energy like living things.
If a non-living thing grows, it’s not through the same process we do. It only grows through adding exterior materials. Like that pile of dirty washing on your floor ‘grows’ – it’s because you’re adding extra items.
Like a computer, it doesn’t eat food, excretes any waste, reproduces any baby computers (although that would be cool), and doesn’t breathe or grow. We could make it ‘grow’ by plugging something into it, but it’s not increasing. It moves if we pick it up and move it, but it also cannot move.
Below are some critical characteristics of non-living things.
- Non-living things don’t reproduce, need nutrition, and produce excretion.
- Non-living things don’t have cells.
- Non-living things don’t have a definite shape of their own. Instead, their body depends on their environment, like the water in glass taking the shape of its container. Or a rock’s size will change depending on the climate and landscape.
- Non-living things don’t respire.
- Non-living things don’t grow by themselves without external influence.
- Non-living things won’t die because they’re not alive.
What are living things and non-living things? – examples
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