Video Transcript: Characteristics of Living Things

Characteristics of Living Things

Hi, there, boys and girls! welcome to our podcast on the characteristics of living things. Now in class we discussed, or you discussed amongst yourselves, what you thought were the characteristics that all living things had to share, organisms that are included from the smallest side of the spectrum, which are the bacteria to the largest organisms on Earth today, which includes the blue whale, which can reach about 100 feet in length.

There are actually five characteristics of all living things share here on Earth, every organism in all five kingdoms share these five characteristics that classify them as living things.

So the first thing that we're going to discuss is the organization. Now, the organization of living things are created by cells. So living things are made up of small units that carry out life. And these units are called cells. Now organisms can be one of two things, they can be unicellular, one cell big, or they can be multicellular, with many cells. If we just take a look at this amoeba here, we'll notice that the amoeba is just one cell big, they're very tiny, you don't walk down the street and see a six-foot amoeba moving along across the sidewalk, because they're one cell big. So here inside you can see the nucleus, which is that big, dark spot in the middle. And then all the little circles and dots that you see inside that you might think are cells, they're actually small organelles or small organs that help the cell carry out its activities. So this is an example of a single cell or unicellular organism.

You and I, we have many cells. So we're known as multicellular. Not only do we have many of the same types of cells, but we have many different kinds of cells. So here in this picture, you're looking at a slide of cheek cells. Now, our body also includes cells, such as muscle cells, blood cells, and nerve cells, amongst many other kinds of cells. So being that we have many of one type, and then many types of cells that makes us multicellular.

The second characteristic that all living things share is that we respond to the environment. So living things interact with their environment. And when we interact with the environment, we interact with the changes in the environment. So when the environment changes, and those changes are called a stimulus, we react to it, showing a response. Not only do we react but all other things do. So for example, here we have a picture of a venus flytrap. So let's take a look at a video, watch it and walk on through how this is responding to changes in its environment. Alright, so here we have a video on YouTube with a venus flytrap trying to catch a fly, there's the fly trap. And here's the fly. Now, before we get rolling on this, what I want you to think about is the original environment. Now there's nothing in the fly trap. So that's why the leaves are wide open. Now as we hit play, and we start to roll, the film will notice that the flies pretty curious, it's gonna start walking around on this leaf here. Now as this fly is starting to walk around on the leaf, the environment on the inside of the fly trap has now changed when we saw it earlier, there was really nothing on the inside of the fly trap. And now this fly is walking on it. And when the fly walks in the fly traps leaves, it's now putting pressure on the fly trap itself. So whereas there was no pressure before in the original environment, the fly walking on it now adds pressure and now the environment has changed. Since the pressure has changed the environment, the pressure is known as a stimulus. And as you guys know, this movie never ends well for the fly in the fly trap. So with the presence of a new stimulus on the leaves, a response is going to happen. And the response is the closing of the leaf. And then after the fly trap closes its leaves, they'll digest the fly absorb the nutrients and the end for the fly. So that's an example of stimulus and response.

Now let's talk about stimulus and response in terms of the human body. And we'll use an easy one called body heat. So here's a picture of us soccer player, that'd be one back. And the reason why I like to use athletes because they tend to sweat a lot because they're exercising. And this is something that we can all relate to it as we know if we're sitting on the couch, you're not really doing a lot of physical exercise, we're not going to sweat. In order to sweat we have to burn energy. So as you get up and you do exercise, you either play soccer at soccer practice field hockey practice, basketball practice, football practice, volleyball practice, if you exercise enough, your body burns up a lot of energy, and you tend to get hot. And when you get hot, your temperature inside of your body rises to the original environment where we're nice and comfortable at body temperature. 98.6F has now increased to get hot after we exercise. So the stimulus is the change in the body temperature. As the body temperature gets too hot. Our body responds to that increase in heat. And as we know when we get too warm, our body sweats. There's the response So the stimulus is the increase in body heat, the responses the sweating that our body does. And what the sweat does is it evaporates and cools our body temperature. And when our body gets cool enough, we stopped sweating, and then we're comfortable again. Now the reason why we do this is because our body is trying to maintain a stable internal environment, which means it wants to keep the body temperature at 98.6F at all times. And when we're trying to keep things at a stable environment, we're maintaining what's called homeostasis. Homeostasis is the maintenance of a stable internal environment.

That leads us to our next characteristic. All living things use energy. Now organisms use energy to carry out activities such as homeostasis, as we were saying, and other activities such as running, jumping, talking, texting, typing on Facebook, playing your video games, we even burn energy while we sleep because our heart is beating, and our muscles are contracting to help us breathe. Some organisms use a different form of energy, we use sugar in our body as fuel to make energy. But other organisms use sunlight, such as plants. So plants use the sun energy to make food. So what's going to happen is sunlight from the sun is going to hit these leaves, and the leaves are going to absorb the sunlight and create a sugar so it can use to make energy. So now the plants get sun energy, they use it to make energy for themselves. Now if we take this plant and grind it into a food, the energy inside of the plant is now inside of the food and you get your energy when oxygen reacts with the food. So as you eat the spaghetti, so to speak, the sugar from the plant that is now in the spaghetti will get into your cells. And then the oxygen you breathe in will react with that. And it'll give you the energy that you need to carry out life processes.

A fourth characteristic of living things includes reproduction. organisms reproduce when they create more of their own offspring. And there's two types of reproduction that organisms can carry out. Some organisms carry out a sexual reproduction. And some organisms carry out sexual reproduction. So let's take a look at what asexual reproduction looks like. Typically, this is a bacterial cell. And asexual reproduction starts out with one parent. So already reproduction has started here, one cell split into two. And then what we'll see is that these two cells will then elongate and split into four cells. And then these four cells will turn into eight cells, that eight will turn into 16, then 32. And before you know it, as time goes by this population of bacteria has grown as asexual reproduction is taking place. So that's asexual reproduction.

Now, sexual reproduction involves two parents, and the reason why it involves to parents because they need to use the male sex cell and the female sex cell. So an offspring are produced by sexual reproduction. It's caused by the sperm cell from the male fertilizing the egg cell, the female, by getting inside, and then the offspring going to have shared characteristics. So that's why offspring look a little bit like mom and dad, they're getting genes and characteristics from both sides of the family. That's what sexual reproduction is.

Now, reproduction leads us into our final and last characteristic of all living things. All living things grow and develop. So a multi-celled organism like yourself, when you grow, produces more cells. So as you get taller, throughout school, until you reach a maximum height, your body is going to continue to make more cells, you have more cells in your body now than you did when you were a tiny little baby, a single cell organism, all they're going to do is just get bigger, so it's gonna get bigger in size. But remember, they don't get too big. Even though they get larger, they don't get big at all in reference to the rest of the world.

Now as organisms grow, they tend to change. And these changes are called development. So if you take a look here, or even if you take a look at your own baby picture from when you were zero months old, and when you were first born to your picture now there's a big difference in how you look back then, and how you look now. Now, this is a picture of my daughter, Riley. And this picture on the left where she's wearing the pink pants was taken when she was first born. And the picture on the right here was taken at one year later. So in within one year, obviously she's grown so she's produced more cells in that whole year, but she doesn't look very much like the baby she was before. So she's got a little bit darker skin. She's got more Asian features like I do, but as she turned 12 months, those Asian features tend to be less obvious now. So in that 12 month span, she's changed a lot. So that's what happens with humans. And then she'll continue to change her appearance as she continues to develop into an adult.

Plants do the same thing as well. Plants start out as seeds, but they change and develop over time. So if we take a look here, you'll see that the seed that's located right here has created a primary root in the stem. And then as it begins to grow, you'll notice that it no longer looks like a seed, it's going to start to develop leaves, and maybe even flowers if it's a flowering plant, and other structures. So this plan is going to change as it gets older and older and older. So in summary, boys and girls always remember the five characteristics that all living things share from you down to bacteria are: one, that they're organized and made up of cells; two, they respond to their environment to maintain homeostasis. Three, they use energy in some form, either to do work or something like running around, or they use energy to make food like plants ;four, living things also reproduce, which means they produce offspring and create more of their own. And they can reproduce in either one of two ways, a sexual reproduction and sexual reproduction. And lastly, those offspring will eventually grow by creating more cells if it's multicellular, or just get bigger. If it's a one celled organism and develop they will change their appearance and structures over time. Okay, boys and girls, that concludes tonight's podcast. Thank you so much for your time.