Practice these TOEFL iBT listening tests to help you score high in the TOEFL Listening Section. Check the correct answers and audio transcripts below. This video is in the series of NEW TOEFL iBT Tests 2015.
Listen to part of a conversation between two students. The woman is helping the man review for a biology examination.
Male Student
OK, so . . . what do you think we should go over next?
Female Student
How about if we go over this stuff about how bacteria become resistant to antibiotics.
Male Student
OK.
Female Student
Um, but first of all, though, how many pages do we have left? I told my roommate I’d
meet her at the library at seven o’clock.
Male Student
Ummm . . . There’s only a few pages left. We should be finished in a few minutes.
Female Student
OK. So, ummm . . .
Male Student
About how bacteria become resistant to antibiotics.
Female Student
Oh yeah, OK. So you know that some bacteria cells are able to resist the drugs we use
against them, and that’s because they have these special genes that, like, protect them
from the drugs.
Male Student
Right. If I remember correctly, I think the genes like . . . weaken the antibiotics, or like
. . . stop the antibiotics from getting into the bacteria cell, something like that?
Female Student
Exactly. So when bacteria have these genes, it’s very difficult for the antibiotics to kill
the bacteria.
Male Student
Right.
Female Student
So, do you remember what those genes are called?
Male Student
Umm . . .
Female Student
Resistance genes.
Male Student
Resistance genes. Right. Resistance genes. OK.
Female Student
And that makes sense, right? Because they help the bacteria resist the antibiotics.
Male Student
Yeah, that makes sense. OK.
Female Student
OK. But the question is: how do bacteria get the resistance genes?
Male Student
How do they get the resistance genes? They just inherit them from the parent cell,
right?
Female Student
OK, yeah, that’s true. They can inherit them from the parent cell, but that’s not what
I’m talking about.
Male Student
OK.
Female Student
I’m talking about how they get resistance genes from other cells in their environment,
you know, from the other cells around them.
Male Student
Oh, I see what you mean. Umm, is that that stuff about “hopping genes,” or something
like that?
Female Student
Right. Although actually they’re called “jumping genes,” not “hopping genes.”
Male Student
Oh, OK. Jumping genes.
Female Student
Yeah, but they have another name, too, that I can’t think of. Umm . . . lemme see if I
can find it here in the book . . .
Male Student
I think it’s probably on . . .
Female Student
Oh, OK. Here it is. Transposons. That’s what they’re called.
Male Student
Lemme see. OK. Trans . . . po . . . sons . . . trans . . . posons. So “transposon” is another
name for a jumping gene?
Female Student
Right. And these transposons are, you know, like, little bits of DNA that are able to
move from one cell to another. That’s why they’re called “jumping genes.” They kind
of, you know, “jump” from one cell to another.
Male Student
OK.
Female Student
And these transposons are how resistance genes are able to get from one bacteria cell
to another bacteria cell. What happens is that a resistance gene from one cell attaches
itself to a transposon and then, when the transposon jumps to another cell . . .
Male Student
The other cell gets the resistance gene and . . .
Female Student
Right.
Male Student
That’s how it becomes resistant to antibiotics.
Female Student
Right.
Male Student
Wow. That’s really cool. So that’s how it happens.
Female Student
That’s how it happens.
Correct answers:
1. D
2. C
3. A
4. A,C
5. C
