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Biology—Semester A

Let's get cellular.

To life, to life, biology! In Semester A of this Biology course, we lift our soda bottles to the study of life.

Chances are, you've heard of cells, genetics, and evolution. After all, you can't watch the news or any show on Hulu without hearing about stem cells, DNA evidence, or the controversy over evolution. But can you tell us:

  • how plants manage to get energy from the sun?
  • how a blond-haired kid can be born to a brown-haired family?
  • why exactly carbs are not the evil enemy the media has made them out to be, but the one molecule essential to human survival?

Our lessons, glossaries, readings, and activities could help you out there, dontcha think? Tagged with the Next Generation Science Standards, our Biology course has everything you need to make science your biomass.

P.S. Biology is a two-semester course. You're looking at Semester A, but you can check out Semester B here.

Course Breakdown

Unit 1. Introduction to Biology

In this introductory unit, we'll answer the big questions of life. No, really. We'll ask the question, "Do you even lift, bro?" Actually, this unit is about the other one, "What is life?" You'll also get comfortable with other big issues of biology, including ye olde scientific method and how biological systems are organized.

Unit 2. The Chemistry of Life

What better way to get acquainted with biology than through...chemistry? That's right; when it comes to life, it's chemical all the way down. (We haven't confirmed how far the turtles go down, but it's pretty far.) In this unit, we'll go straight to the bottom of the biological pyramid by learning some foundational concepts, including atomic bonding, the properties of water, and macromolecules.

Unit 3. Cells

Movin' on up the biological pyramid, we come to the smallest unit of life: the cell. This unit covers the properties and components of eukaryotes and prokaryotes, enzymes, osmosis and diffusion, and everyone's favorite cellular process: mitosis.

Unit 4. Biochemical Pathways

The phrase "biochemical pathway" sounds like the driest, most boring thing ever, but it's actually a topic near and dear your stomach. It's the process by which our nom-noms are broken down by our cells into energy. This unit covers the basics of cellular respiration (aerobic and anaerobic style) and plants' superpower, photosynthesis.

Unit 5. Genetics

Peas changed the world. True story. In this unit, we'll find out how Gregor Mendel discovered genes, and indirectly founded the field of genetics, by observing peas. You'll get cozy with alleles, meiosis, Punnett squares, genetic disorders (well, not too cozy), and other genetics issues.

Unit 6. Molecular Genetics

Our quest to gain total genetic mastery continues in this unit on DNA, the molecule of inheritance. Replication, transcription, and translation will make their appearances here, culminating with some discussion of biotechnology. Mwa ha ha...! Er, pay no mind to that mad science cackle. We totally don't have any plans for creating a race of super apes.

Sample Lesson - Introduction

Lesson 3: Cell Transport

Cell membranes in a nutshell: Cells have stuff inside of them that make them function, like organelles and cytoplasm and a nucleus. Cell membranes consist of a thin layer of plasma, which holds all of these goodies within cells and keeps them separated from the harsh, outside environment.

A dog lounging on top of some light reading.
This is not osmosis.

Think of the cell membrane as the dreaded airport security you have to pass through in order to catch your flight. Those guys don't just let anyone through, and neither does the cell membrane (although the credentials are slightly different, we hear). In other words, the cell membrane keeps the cell safe. It's the bodyguard, the bouncer, the troll under the bridge, the three-headed dog which needs to be appeased by a Scooby snack.

The question is, then, how does the cell membrane select what goes in and out of the cell?

The cell membrane is like Goldilocks. You know, the porridge is too hot, too cold, or just right. The cell doesn't want too much or too little but just the right amount of water and solutes in order to keep the cell comfortable. So the cell membrane regulates how much stuff goes in and out through two processes: osmosis and diffusion. Remember those?

If you've ever been stuck on a hot, crowded, stuffy elevator on Friday afternoon, you know what happens when the doors open: everyone makes a break for it, spreading out as far as possible. This isn't terribly unlike what happens during diffusion. Molecules move from areas of high concentration to low concentration, just like the people on the elevator. Only, of course, molecules aren't in a hurry to get to their weekend started, they do it because of forces and other physics-type stuff. And since scientists seem to take delight in coming up with a new word for everything, they have a special one for the diffusion of water: osmosis. One basic process, two names. Fin.

These two processes are the main ways by which water and other goodies (solutes, if you want to be all science-like) move through the cell membrane, going into and out of the cell.

  • Course Length: 18 weeks
  • Grade Levels: 9, 10, 11, 12
  • Course Type: Basic
  • Category:
    • High School
    • Science
  • Prerequisites:
    Pre-Algebra I—Semester A
    Pre-Algebra I—Semester B
    Pre-Algebra II—Semester A
    Pre-Algebra II—Semester B

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