Introduction to Middle school biology
About this video
Sal Khan and Iman Howard introduce the Middle School Biology course. They explain that biology is the study of life and preview big ideas the course covers: traits, energy and photosynthesis, and evolution, including natural and artificial selection.
You'll be able to
- explain that biology is the study of life.
- name some big topics in middle school biology, like traits, energy and evolution.
- describe photosynthesis as plants using light energy from the sun to make their own food.
Key words
- Biology
- The study of life and living things.
- Trait
- A feature of an organism, like its size, color or behavior, that helps it interact with its environment.
- Photosynthesis
- The process plants use to turn light energy from the sun into their own food.
- Evolution
- How living things change over time, based on their traits.
- Artificial selection
- When humans choose which traits get passed on, like breeding dogs to be big or small.
Transcript
- Hi, everyone. Sal Kahn here. And welcome to Middle School Biology. I have Iman Howard here, who manages our STEM content. Welcome, Iman, and why should folks care about middle school biology?
- Biology is the study of life. And so, in this course, it really answers why are things the way they are, why do you look the way they do, why do I look the way I do, and how every organism on Earth has a really special purpose and a special trait. And based on these traits, it helps them interact with their environment.
We even talk about energy. And energy can't be created and it can't be destroyed. It actually cycles as matter through an ecosystem. And it even has this really cool chemical reactions called photosynthesis, where plants use light energy from the sun and they make their own food, which is insane.
I think about organisms like the gorilla that are super-big and strong and they don't go and eat a cow. They go and eat plants because that's like getting energy right from the source. And then finally, we talk about evolution. Based on our traits, how have we changed over time?
And how some of our natural traits were selected by the environment that create those changes or even how humans, we have something called artificial selection, which explains why your dog's so cute. Whether it's 100 pounds or five pounds, we did that. What do you think's cool about it, Sal?
- Oh, well, you know, biology's trying to answer, I mean, to your point, the questions of life, which we still don't understand a lot about but like what makes us us and to realize that we don't exist as human beings in isolation. We're part of an ecosystem. We're part of a story, a narrative that's been going on for millions and billions of years.
The fact that we're made up of trillions of cells, each of them with DNA that can describe who we are, how did all of this complexity come about? This is maybe the most mind-blowing topic that we're really at just the beginning of this journey. So I think folks are gonna be really, really excited to or it's gonna be really interesting to see all of the things that they get to learn.
- Well, let's dig in. (enthusiastic chiming)
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