Whoa.
I think what the kids leave with is
they come inspired that
science is creative,
it's exciting, it's relevant, it's different,
it's not about memorization of things...
So we predicted that one was gonna glow
...it's learning by doing:
it's exploring.
It's glowing green, 'k
I'm Julianne Zedalis. I teach at the Bishop's School,
which is in La Jolla, California, and I teach AP Bio.
I'm the lead instructor for AP Bio.
The hardest thing about inquiry is really, for the teacher, to get the shift
from a teacher-directed point of view -
a teacher-directed approach -
to a student-directed inquiry-based approach.
And it comes back: the whole purpose of inquiry is when
students start acting like scientists
they start thinking like scientists.
And it's in the process.
The pre-lab is I have them making diagrams
to show me transformation using the pGLO plasmid
what's what they would expect to happen,
and the procedure.
There's many different levels of inquiry,
perfect
and at this level, it's more
its student-directed, inquiry-based
but teacher-guided.
So that will be open for you to do...
On the first day we literally have them
just go through the basic protocol.
We're gonna be looking at how
organisms can be transformed
to express some new genes...
The first thing always safety issues.
Do you think you may need to put these on?
and I think that's what teachers can do
instead of making
bullet statements:
put everything you possibly can into
the form of a question.
What do you think would happen if you
left the tubes back in the water bath
that's hot for too long?
Kill the bacteria. What else? I heard a good word.
You could denature any enzymes that are involved, okay.
So this one's going to be the control
and we have the experimental [condition].
What's - what's the challenge here
when you have plasmid and bacterial cells?
What's the challenge?
Couple different challenges.
Making the bacteria and plasmid compatiable.
Yes! Okay, you're ready for the pGLO?
I will bring it.
There it is! I see it. Okay then you put it in there,
and now shake it in there.
You've just dropped your plasmid in there, awesome.
You want them to spread out evenly so they can...
...grow.
What do you think might be a more effective way
to label these plates?
Guys, excellent work today.
See you tomorrow
and, hopefully, we'll get some results.
this is my pGLO minus (-).
They're really excited when they come in in day two
because they know, if they have transformed cells,
the cells will glow in the dark.
No.
How 'bout the next plate?
Wha - Whoooooa!
That one's action.
That one grew so much more, too.
So then they get to count their colonies,
they quantify their results -
number of transformants per milligram of DNA plasmid -
and they come up with the transformation efficiency.
Hey,
what pattern is emerging here?
You know if I see them
making mistakes with the calculations -
maybe they're putting the decimal place
in the wrong spot -
I'd let it go,
because part of inquiry is also
letting them self-correct.
Uh, I think
what our group made was
we used 0.08
which is the density
instead of 0.8.
I don't want to make a pun,
but is that a "significant difference,"
okay?
Five...
...four...
...three...
...two...
...one...
take it out.
So then the next day,
they come in, and they're ready to perform
their independent investigations.
So today we're going to change up some variables.
So, for homework last night,
what variables did you come up with
that we can start to generate a list here
on the board?
The time that we heat it for.
Time. Okay.
How much nutrient broth.
A change in temperature with the ice bath
and the, uh, incubator.
If we have increased the pGLO it will get in faster so
we [chose] 12 hours as the incubation time.
It will double the amount of
effectiveness of it.
Yeah do you get
do you think it's going to grow
more than it
did last time?
Yeah.
I bet they'll be, uh,
um,
more
little colonies.
So, if we didn't do that
and we just left it in at room temp
the room temp could close it
but probably at a slower rate
so then more of the plasmid would get out
and then it would have a lower efficiency.
And look at,
and look at what you just connected.
But I like it that,
ya know, as you were thinking now that you're more familiar
with the procedure, okay,
what might not we have done,
and all of a sudden you came up-
God! - remember that, when we seemed to put too much on one plate
and not on the other?
And that's fine, okay,
you won't make that mistake again.
No? Okay, awesome, okay.
Then you'll see these little things. What are they called?
Satellites
Well we've,
we finished the student-directed inquiry
and that's when I really get the different groups involved -
that leads to some great discussions.
So they were transformed
but certainly not as efficiently.
Why do you think that would be?
Because the preincubation step
kinda serves to help
tighten up the membrane here
so that when you heat shock it
it separates.
What could happen at 75?
What could happen at 100?
What would you predict?
I would predict that the higher the temperature
the fewer colonies would grow.
It would kill off more because
if you're already at 65 and you have less colonies in your control
then you know that you've reached,
you've already gone past that peak efficiency.
Chart,
and that would be really interesting, you know,
how high can temperature go
before that's it?
Ours is just one decimal place off-
I know, I think that's, that's why
these values aren't big enough.
For your control then it would be-
"A" and then this one "B."
Okay.
Okay, so let's try that.
Wait, isn't it 95 divided by this number?
You know, one thing that I stress in my classroom is
every fact that you find in the textbook
there was some kind of investigation behind that information.
That looks much better.
I'll go write this up.
So that's what I tell them:
that you are not just learning information,
you are actually creating information.
They have become engaged students,
students who can problem-solve,
students who can think things through,
students that can look at novel situations
and apply it to past knowledge.
These are lifelong skills,
and I think, at the end of the day,
that's what teaching is all about.