Resource Information

These resources, while free, are not openly licensed so they may not be altered from the original form.  Here I have supplied a link to the resources and a transcript of the video.  You can use the transcript as a basis to create your own worksheet, quiz, or as an additional resource for students who are differently-abled. I find it most helpful to play the video to the class and stop it every minute or two to further elaborate what Mr. Anderson is explaining. 

 You can highlight sentences in the transcript you would especially like the students to take notes on, and pause the video while you write the notes on the board.  This demonstrates note-taking skills for the students in real-time.  

You can also pause the video as the answers to the worksheet questions appear, to give the students time to answer the questions.This can also be given as a pre-lecture assignment to be done independently.  This works especially well if students have 1:1 computers and can do the assignment before class. 

 It also makes an excellent substitute lesson plan.

Cell Communication Video Summary

Paul Andersen discusses cell communication. He begins by explaining how he communicates with other individuals using various forms of electronic communication. He them explains how cells communicate when the distance between them is big, small, and zero. He explains how antigen presenting cells pass information on antigen structure by touching in the immune response.

Link to the Resource

http://www.bozemanscience.com/037-cell-communication

Education Resources

Cell Communication Review Worksheet - Winnie Litten

Transcript:

"Hi. It's Mr. Andersen and welcome to biology essentials video 37. This is on

cell communication. In other words how cells communicate with other cells. And what I thought

I'd do is start with some analogies. I want to show you how I communicate with other people.

And how those communications are similar to the communications that we see in cells. So

let's first of all start with the post-it note. Post-it note works great if you want

to take a message and hand it specifically to someone else. And so for example, let's

say I have a grocery list. I write down the things that we need at home, I hand it to

my son and I say please get these things at the store. He can always check on the list

to make sure it's matching up with the things that we actually require. And so it works

great. But you have to hand it off from one person to another. Next is the e-mail. And

so Gmail works great for me. If I want to send a message to a student, a specific student,

then I send an e-mail. Works great because I can send it to a specific student. I don't

have to physically be next to that person to send it to them. And then the last one

would be Facebook. Like a, I don't do many status updates, but if I were to post this,

"Working on a communication podcast by myself. Ironic." A Facebook status post is not going

to one person, it's going to all of my friends and so then they can determine if they want

to like it or dislike it or ignore it or unfriend me as a result of that. And so those are three

ways that I communicate with people. And that is really similar to the way cells communicate.

And so the first one is when there's no distance between cells. In other words you have to

make sure a message gets from one cell to another, then we can use cell to cell contact.

And so an example I'll talk about in this is the antigen presenting cell. And so that's

when one cell is sending a message to another. Also like plant cells for example have these

little holes called plasmodesmata and they can actually send messages from cell to cell.

Next one I'll talk about are local regulators. If it's a distance that's short and I want

to make sure that it goes to one other cell, cell to cell, I could use something called

a local regulator. And so an example I'll talk about is when you have a neuron connected

to another neuron through a synapse. You can send a neurotransmitter to make sure that

message gets across. Again it's going just from one cell to another. Let's say it's a

distance that's long or an audience that's large, you want to send that information,

we could use something like a hormone. And so the one I'll talk about is human growth

hormone. And nice thing about that is you can send it from not only just one cell or

excuse not just to one cell, you can send it to multiple cells. And then they can figure

out based on that message if they really want to act on it or not. And that's why it's a

lot like a status post. And so let's first of all start with a contact, in other words

specific contact between two cells. And the example I'm using here is the immune response.

And so an antigen is an invader. So it could be for example a bacteria or a virus. And

so we have cells called antigen presenting cells. An example would be a macrophage. And

it can actually sense the shape and then pass that off to make antibodies, more macrophages

and then killer T cells. And so what sits in the center of this whole thing is the T

helper cell. And it has to know specifically what the shape is. And so let me show you,

I've made a little animation that explains this. This is like the post-it note. And so

let's say we have our antigens. So we have our virus. And this would be our macrophage.

And so what it's going to do is it's going to grab on to that antigen. And it's going

to envelope it. It'll put it inside this little phagocyte or this little phagosome which is

a little bubble. It'll then have a lysosome come next to it that will spill some digestive

enzymes into it and it'll chop up it up into a million little pieces. Next it will let

that go, but you'll notice as it moves out that it's actually, part of it is being carried

to the surface. The shape of a part of that antigen is carried to the surface. And now

we have our helper T cell. And so the helper T cell is going to pass off, let me get a

marker, it's going to pass that shape to the helper T cell. And so that protein that was

inside the macrophage is called the MHC2. It's a protein, major histocompatability complex

2. It's just a protein that brings the surface of that antigen to its surface. It's then

going to link up with a CD4, which is another protein on the surface of the helper T cell.

So let me get all of this scribbling out of the way. So there will actually be a connection

between those two cells. And what it's really sending is this shape of that antigen to that

helper T cell. Okay. Now it's activated the helper T cell. It know the shape of that antigen

so the macrophage isn't required anymore. It's going to go eat some more of those antigens.

And now that helper T cell can send that message to a B cell. So it can make plasma cells.

Make more antibodies. It could also make more memory cells. It's also going to activate

a killer T cell. And a killer T cell now knows that shape as well. And it's going to target

any cell inside our body that's actually infected with that. And so by passing that message

off just like a post it note, we're sure what that shape is. Next one is the idea of a local

regulator. Now there's a distance between those two cells but we still have to make

sure that message gets across. A perfect example of this would be when neurons are connected.

And so a neuron is going to take a message. So let's say I poke my finger right here.

It's going to send that message eventually to my spinal cord, eventually to my brain

and then back again so it can act on that. And so that message is going to travel in

this direction. And it's eventually going to hit another neuron. And so it's eventually

going to have to travel over here. But what's interesting is right here where those two

neurons come together, they're not actually connected. Now we still want to make sure

that message gets across. Because we want to make sure that message keeps going all

the way down here to the brain. But they're not connected. And so we have to use a local

regulator to make sure that message gets across. An example would be a neurotransmitter. And

so that message is coming down neuron A. It's going to move down neuron B. But the way it

works is that we're actually going to release chemicals. Those are called neurotransmitters.

They'll move across that synapse or across that gap. They're going to open up some other

channels. Which is eventually going to get an influx of ions and it's eventually going

to send that message on it's way. And so these right here, neurotransmitters, are chemicals.

And those chemical signals are going to float right across that gap. Now they're not really

going to float out to another neuron. They're quickly going to breakdown. And so it's just

like an e-mail. It's a message going from this cell to this cell. Now you might think

if you're smart, you might think what's the point of that? In other words, wouldn't it

be smarter to just have those two neurons connected together so the message is going

to go across quicker? That's a really good question. And what we think, scientists think,

is that by opening it up, by allowing theses local regulators to go across, it gives us

control over how much of that signal gets through. If it gets through. If we can block

this signal so it doesn't get across. And so we think that our brains have gotten bigger

and bigger and bigger by adding more neurons, but probably what's more important than adding

more neurons is adding these connections between neurons. Let me give you an example of this.

I'm a distance runner and so I love these beta endorphins. Endorphins are natural opiates

made by your body. Now what they do is they block pain. And so if you go for a run, here's

Paula Radcliffe, she's a marathon runner, if you go for a run and you're out there for

10 minutes, you won't feel these. Or 40 minutes, you won't feel these. But a couple of hours

in, if you're out there for two hours, if you could make it that long, you're body is

going to start secreting these beta endorphins. And those are neurotransmitters. They'll move

into nerves in your central nervous system. What they'll do is they'll block pain. And

so even though the signal is actually a pain is traveling into your brain from your body.

It really hurts to run that far, you're actually breaking it, that connection. And that shows

you how it's important to have control over that synapse. Now humans have created things

that mirror this. And so heroin or morphine, they really resemble the structure of endorphins

because they're going to trigger those same responses inside our brain. Last thing I want

to talk about is that Facebook status post. When you want to send a message and it's going

to go to everybody. And they're going to figure out how to act on that. An example I'll talk

about would be, I mean this is a hormone that we're now talking about. A hormone is simply

going to be a chemical. And that chemical is going to spread throughout your whole body.

And so an example of one would be the growth hormone. Growth hormone is especially going

to be secreted by the pituitary as a human goes through puberty. And so as your body

gets larger and larger and larger, the way that works is we secrete a growth hormone.

The cells are going to pick it up. So for example muscles will grow. Bones will grow.

And here's actually a list of all the things that will happen as we increase the amount

of growth hormone. So for example all of the organs will grow but the brain won't grow.

And we'll get glucogenesis in the liver. Or uptake of glucose. Or stimulates the immune

response. In other words, all of these cells in your body are receiving that same message

from human growth hormone. But they're acting on that. And so that's like that status post.

It goes to everybody, but you can choose to like it or ignore it or act as a result of

that. Sometimes the message will go out of control. And so this is Robert Wadlow. Robert

Wadlow is a pituitary giant. And the reason he was a pituitary giant we now know is that

he had a tumor that was pushing on his pituitary gland. As a result of that he created more

human growth hormone. And more human growth hormone and more human growth hormone and

you can see he was, I don't know, well over 8 feet tall. And so this is just a hormone

and it's acting on all the cells in your body. And so when the distance is large and you

want to touch a lot of different cells, you're going to use something like a hormone. And

so that's how cells communicate. It's not that different from the way that we communicate.

You just have to know your audience and send a message that's appropriate. So I hope that's

helpful."