Here's another straightforward one,
"Which of the following cells in
the blood do not have a nucleus?"
Well, let's see. We got A, B, C, D,
down on your paper.
Okay. Now let's look at white blood cells.
I always like to start at the top
and work my way down.
But you don't have to. You can start in
the middle. You can start in the bottom.
Whatever is comfortable for you,
but I kind of get -- I'm a creature of
habit. I like to start at the top.
So, which of them don't have a
nucleus? So I'm going to say,
"Does the white blood cell have a nucleus?"
Oh, yeah, they're the ones that have like --
they even have PMNs, the polynuclei.
They have lots of them, so I'm
going to eliminate A.
What about basophils? Do they have nucleus?
Yeah, they do.
What about platelets? Do platelets have
a nucleus because I'm looking for the one
that doesn't have a nucleus? They do.
So, I'm left with red blood cells.
I sure hope that's the right answer,
because I've eliminated all 3.
Red blood cells, do they have a nucleus?
No, they don't.
Remember, red blood cells are just like
a sack for carrying around the hemoglobin.
So the correct answer is D.
Now, once I've eliminated 3,
I have my final answer.
You go back up to the stem of the
question and say, "Does this make sense?"
When I look at this, and I say,
"Which of the following cells in the
blood do not have a nucleus?"
Right. I agree. "Red blood cells"
is the right answer.
Okay. We're done with the warm up.
Now let's go to some serious questions.