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Course: Middle school biology > Unit 7
Lesson 3: MutationsMutations
Changes (mutations) to genes can result in changes to proteins, which can affect the structures and functions of the organism and thereby change traits. Some changes are beneficial, others harmful, and some neutral to the organism. Created by Sal Khan.
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- Is there any examples of mutation you can give me? Do mutations count as someone having an odd appearance? Like something that isn't normal?(8 votes)
- An example would be something like a certain people in Europe that have better water vision due to the fact that they are a fishing community.(16 votes)
- Wait now I'm confused about Spiderman. He got bit by a spider so do snakes,spiders,etc give DNA if they are poisonous and they bite you,and that can cause mutations? Or am I getting this all wrong haha :)🐍🕷😁(14 votes)
- Getting bit by a spider's venom does not make it so you have their DNA. A spider's venom contains little to none of DNA. Plus their bodies do not create their venom through the same way they make cells or protein.(2 votes)
- at1:34, he says "We don't know about too many mutations that create the ability to fly or stick to walls.", what does he mean by "We don't know about too many"..? Are there really superpowers? 0_0(5 votes)
- No he's just joking with us to make it more enjoyable. He tries to make it as enjoyable and informative as possible by doing jokes or changing his pitch up and down to make you concentrate more. Not like the teachers in movies when they make them seem like they talk all day in same flat pitch about same flat subject.(5 votes)
- can mutation really alter your immune system? I mean in movies it can but can you do it in real life? thanks(6 votes)
- Yes, it probably can because your immune system is also based on your DNA, so probably it can. But I hope no one will get THAT mutation!(4 votes)
- how is your day going(6 votes)
- good Thank you(3 votes)
- can you mix an ostrige and a chicken to get a small ostrige or a big chicken(4 votes)
- it would probably not work in the first place because there are numerous barriers that prevents making hybrid animals. Like the two animals might not be attracted to each other, or even if they produced a child, the chromosome needs to be even. If it doesn't the new hybrid won't be able to breed with others. The white cells might think that the sperm cells are foreign and kill them off.(3 votes)
- can mutation really alter your immune system? I mean in movies it can but can you do it in real life? thanks(3 votes)
- When he talks about proteins is he talking about like fish and other foods we eat that have protein and if so then how is it that the food we eat majorly affects our DNA?(3 votes)
- can you mix an ostrige and a chicken to get a small ostrige or a big chicken(3 votes)
- Why are the amino acids labeled with nucleotides in a gene when proteins do not have dna in them?(3 votes)
- the nucleotides make up the protein(0 votes)
Video transcript
- [Instructor] In this video, we're gonna talk a little
bit about mutations, and I wanna apologize ahead of time. My voice is a little strange today. I rode more roller coasters than I thought I would yesterday, and I screamed a little bit. But anyway, (chuckles) what we see right over here is what's often known as the
central dogma of biology. It explains how we go from
information in our DNA, which is really sequences of nucleotides, genes are segments of our DNA
that code for specific things. So we see these nucleotides, which we denote with A, C, Gs, and Ts. And every three of them,
that's known as a codon, and for every three of them, it's associated with an amino acid. And in other future parts
of your biology education, you'll go into more depth on the molecular
structures of amino acids. But what you need to know now is the amino acids are
essentially strung together. And then they create proteins. And proteins have all sorts
of functions in your body. To a large degree, they make you, you. They construct what you are. So this is a simplified version of how we go from DNA,
to you, to some degree. Now, mutations, as you might know, even when you watch some movies, these are changes in DNA. You might have seen superheroes be exposed to radiation
or some type of chemical, and then they get mutations, and then all of a sudden they have powers. Well, we don't know
about too many mutations that create the ability to
fly or to stick to walls. But mutations are a way that
we get new genetic information in the gene pool. Now you might be saying, wait, I already know
about sexual reproduction. Sexual reproduction creates variation. And that's true. Sexual reproduction creates variation but it really just
shuffles around the genes and the chromosomes they're on that exist already inside of a gene pool. Mutations are actually
changes in the genes. Now, where do these mutations come from? Well, there are sometimes
errors when DNA is copied, but can also happen from
environmental influences, like radiation or other things. Now, as you can imagine, many times, if you were
to just all of a sudden eliminate some nucleotides, or if you were to change
them into something else, that might be harmful. All of a sudden it might
code for an amino acid here that does not allow this
protein to function properly. Sometimes, it can be beneficial. And that's how we can get new
versions of genes, alleles, or new genes altogether. All of a sudden this became that, this becomes a different amino acid, maybe this protein functions better. And then as you can imagine, sometimes, it doesn't matter at all. Maybe the different amino acid here really doesn't change the
structure of this protein. And in some cases, you can
even change a nucleotide and it still codes for
the same amino acid.