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Classification of amino acids | Chemical processes | MCAT | Khan Academy

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Amino acids can be classified according to their side chain's chemical properties (the R-group). This video will show you how! By Tracy Kovach. Created by Tracy Kim Kovach.
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Опубликовано:

28 авг 2024

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Комментарии : 124

@Owneyone 6 лет назад

Explained this in a much easier way than my professor. Thank you!

@nerfguns1234 4 года назад

The more I turned down my volume, the louder she got

@mishca5116 3 года назад

It is the vocal fry ...makes her voice so hard on my ears.

@hopeenvy 3 года назад

Same😪

@davidstevens9025 3 года назад

Are you wearing headphones?

@jessjms1181 7 лет назад

Your voice is articulate and easy to focus on

@Eddiecole_ 4 года назад

To help with the confusion involving the Aromatic Tyrosine and Tryptophan, as well as the Non-Aromatic Methionine; let it be considered that all three are Amphipathic amino acids. This means that they tend to have both polar and non-polar characteristics within their structures. Amphipathic amino acids are often found at the surface of proteins or lipid membranes, which is why they are sometimes classified as polar. However, even though Tyr and Trp have polar groups (-OH and the indol nitrogen), which can H-bond, these AAs are still hydrophobic due to their large hydrocarbon content. Methionine, on the other hand, tends to stay closer to the center of cells because it is mostly non-polar due to having the non-polar hydrocarbons, which is why most of the time you see that it is such. However, it is also weakly polar due to its thioether in the side chain, giving it amphipathic characteristics. *knowing the polarity properties of the groups "within" side chains will help you get a better understanding of amino acids overall characteristics.*

@ShinySephiroth1 5 лет назад

Who else listens to a particular video over and over and over again until you get that light bulb moment on each category discussed?

@torlarsen2212 4 года назад

Same here man, science high five!

@alimamstudying9462 2 года назад

This video saved me thank u so much❤❤

@benjaminlee5976 8 лет назад

Alcohol groups as side chains make amino acids polar.

@shalminpohtam0999 5 лет назад

Yup..it forms h-bondig right with water...

@tinotendamuungani6532 Год назад

powerful presentation ,you really explained it better and it's now easier for me to classify amino acids ..Thank you

@neechiokwor 8 лет назад

Great video really helped me understand my text. NOTE: The -CH2 group is missing in the structure of Tyrosine. Thanks!

@girtonm 5 лет назад

Regarding the drawing of tyrosine, the CH2 group is there para to the hydroxyl; it is represented by an angle in the structure.

@kishankumargaur6540 3 года назад

Voice with synchronisation to the written manner is a great idea.....

@llDietryingll 7 лет назад

Thank you so much, very big help for my orgo 2 final exam

@isaacsa8060 10 лет назад

Thank You!

@MolecularArts 10 лет назад

1:42 This is probably beyond the scope of this video, but the hydrophobic amino acids do interact with water through van der Waals forces. The hydrophobic effect is very complex and involves subtle entropic effects, for example, hydrophobic side-chains force surrounding water molecules to adopt entropically unfavorable "structured" (clathrate cage) configurations.

@susannadsouza4484 4 года назад

Thank you so much for these lecs!!!!!!

@Muhaymin22 2 года назад

I love your voice that makes me feel good.

@MolecularArts 10 лет назад

4:36 Tyrosine is also aromatic.

@JacksonReynolds 8 лет назад

Correct, but I assume she left it out of the group of aromatics due to the polarity conferred to it by its hydroxyl group.

@rachellarson4777 5 лет назад

I thought that since it had an OH group on the arene structure, it turns the arene and the OH into a phenol group, and phenol groups are defiantly polar.

@nyawirawaithaka4993 5 лет назад

Thank you. Very well summarized.

@nujoodalawwad1164 7 лет назад

Actually I love her voice

@tariqahmad5781 6 лет назад

The God has bestowed her with that particular voice and hence cannot be criticised

@user-nd2mb6fv6x 6 месяцев назад

Well explained 🙏🏻☺️

@matt.pma.kresnaputra5458 5 лет назад

CAUTION: Tyrosine is NOT considered hydrophilic/polar... the AAMC considers tyrosine as a non-polar/hydrophobic aromatic amino acid

@LinhTruong-jk8zq 6 лет назад

Big thanks for you, you’ve made this aa stuffs be an easier one to acquire

@ancientmedia6315 3 года назад

keep it up wonder full lecture

@torlarsen2212 4 года назад

Hey umm thank you so much for this!! You're voice is really cute by the way

@adelzekry684 3 года назад

@I'M NOT sAD I'M JUsT TIRED lmao

@tijsdjoos8663 4 года назад

I really love her voice

@tijsdjoos8663 4 года назад

quality of the video was ok

@plantbasednatural2548 6 лет назад

But methionine has a sulphur atom in the side chain so why is it non-polar if the neutral polar amino acids are that way because they have either an oxygen or a sulphur atom in the side chain?

@akingbolamoyosore6560 3 года назад

Thank you

@sciencenerd7639 2 года назад

Very nice, but I would like to point out that tyrosine really is hydrophobic. This is because, even though it has a hydroxyl, the aromatic portion is so big and bulky that the amino acid is hydrophobic overall.

@babygurll7 6 лет назад

But asparagine and glutamine also have nitrogens in their side chains. From how you explained remembering basic amino acids (by seeing there are nitrogens) shouldn't asparagine and glutamine also be basic ? You skipped over them in your neutral amino acid explanation saying those have oxygens or sulfur.

@umaranwar2293 5 лет назад

The have nitrogen but to a side not in the straight linear chain that's why not counted. As well as tryptophan has nitrogen but not counted because the aromatic behaviour prevent it to make amino acid basic.

@Ali_Haider3130 2 года назад

thank you very much

@floydkazenene9585 10 лет назад

wooooooooow! good lecture keep it high

@xXSherviNXx 9 лет назад

Isn't Tyrosine aromatic?

@nathanstumpf 9 лет назад

It is aromatic for sure, but also polar I guess?

@neechiokwor 8 лет назад

+nathan stumpf Yes that is due to the hydroxyl group it bears.

@sunnyyoda5511 7 лет назад

Okwor Neechi yes Nathan is right, it has hydroxyl group making it polar

@AmyStylinson 7 лет назад

Right? It's aromatic and it's important that it's classified under aromatic because those 3 contribute to fluorescence

@itskhani1112 3 года назад

Thanks alot.....

@ewwxaca 5 лет назад

Thanks

@linasing100 6 лет назад

Great video!!! helps alot

@sirajuddin8773 2 года назад

I never fully attend the khan academy class becz of its methode plz you change ur methode of lecture regards

@beawesome5090 3 года назад

Thanks 😊 🙏

@poojaramesh1133 2 года назад

Hii there ..shouldn't proline be classified under aromatic side chain group?? please tell me..

@boodobbyslowerrank8035 6 лет назад

THANK YOU!

@MolecularArts 10 лет назад

3:00 Glycine is not normally counted among the hydrophobic amino acids. The side-chain is so small (-H) that the properties of the amino and carboxylic acid groups dominate. Pure glycine is highly soluble in water.

@mygoldentruth 10 лет назад

You're right, at least in near neutral pH (as plasma, or any pH around 3-9) it has both groups charged, thus polar! Nice annotation.

@rebeccakane8854 5 лет назад

0:59 video starts

@parislove5438 4 года назад

Thank youuuuu 🤪

@MyB.S._channel Год назад

'The wife' told me to get ride of my " side piece." I told her I would replace it with my own individual "side chain "

@Dan1418 10 лет назад

I love your voice.

@thefenerbahcesk4156 5 лет назад

So hydrophillic will be on the surface of a protein and hydrophobic in the interior?

@iqrakhan4317 3 года назад

Depends on the type of protein. If it is water soluble protein hydrophilic amino acids will be on the surface while hydrophobic amino acids will be in interior to maintain the protein structure. If it is membrane surface protein then hydrophobic amino acids will be on the surface and hydrophilic amino acids will be in the interior. So it depends upon the type of protein.

@manohad5 7 лет назад

We learnt that there are 5 types of aminoacids Posetive Negative Polar nonPolar and Aromatic can one amino acid be in 2 groups ? because Serine according to you is Polar but it also have charge so not sure wheather i should put it as posetive\ or polar help please ?

@ibi9636 6 лет назад

thankyouuuuu

@sshirish9167 6 лет назад

Nice video......Good explanation :-) :-)........And guys, her voice is perfectly normal

@anish6350 4 года назад

Your sound is aromatic

@sagarkucha9160 6 лет назад

Nice

@ramil8029 4 года назад

People are talking so much trash in the comments, it's ridiculous. With this attitude, I really have no idea why you're watching MCAT prep courses.

@Roxxxycat 6 лет назад

Why is it that in some places Cysteine is Nonpolar and in other places they say it's Polar? ughh which is it

@ecwgct 6 лет назад

What is alkyl? Does it mean alkaline?

@Rohit_Kumar186 5 лет назад

Alkaline means basic in nature while alkyl is formed when one H is removed from an alkane, Like -CH3 is alkyl group( 1 H has been removed from methane i.e CH4) and is called methyl. And that is how you proceeed to other alkanes

@stavroskar9740 6 лет назад

I dont get how aminoacids with oxygen are acidic whereas those with nitrogen are basic, since both elements are electronegative.

@michaelmorgan-ellcessor5221 6 лет назад

Oxygen is more likely to give away protons in the form of a positively charged hydrogen making it more of an acid. Nitrogen however usually receives this proton making it basic. It is helpful to memorize that acids tend to give away protons while bases like to receive them. I hope this helped.

@pizzacheeseman2854 9 месяцев назад

I think cystine is hydrophobic?

@Aafiaeh 3 месяца назад

my textbook teaches tyrosine as nonpolar aromatic

@cat5220 4 года назад

What about glycine?

@jordanhaynes1110 8 лет назад

so I have to Drink a protein sub because I have pku but in the ingredients it says like L-this and L-that any ideas what those are

@unamed5555 8 лет назад

+jordan haynes its in reference to sterochemistry of the molecule itself. L-amino acids are the ones that we use in our body and most commonly found in nature. Someone with PKU should not have to worry about the L- prefixes.

@Jerseygirltrader24 6 лет назад

IMHO, the way she explains the basic aa is not very accurate. Trp has N on the side chain, but it’s non polar. Gln has N on the side chain, but it makes an amide, so it’s polar neutral.

@GodlovesAmerica07 9 лет назад

Methionine has sulfur in its side chain. Shouldn't it be polar? Pls clarify

@iiii7982 9 лет назад

+GodlovesAmerica07 I simplify the real fact, but consider the S is central in methionine' side chain and does not move the electric barycentre.

@Awesiim Год назад

The sulfur in methionine has methyl's on each side, so the dipoles cancel out. In Cysteine the sulfur only has one methyl and has a net dipole

@AshleyxScreamx 7 лет назад

I don't understand this lol I'm gonna fail :(

@ramyemad6325 5 лет назад

Ashley. Feel you got an exam the day after tomorrow :'(

@emmarichard1709 5 лет назад

Did you?

@emmarichard1709 4 года назад

John Wayne I passed actually lol this was so long ago wow

@liamjacques1910 5 лет назад

Good video, but the explanations and groupings aren't entirely correct.

@MolecularArts 10 лет назад

1:05 There are 21 proteinogenic amino acids in most organisms! The 21st is selenocysteine.

@Tosolo-dh2co 2 года назад

Appriciate the work, but this video has a lot of small damning mistakes which makes it counterproductive and leads to us students having to spend a lot of time looking things up.

@josephsanjuan6235 4 года назад

isn't histidine aromatic?

@David-Eng 7 лет назад

I think she's got a pretty voice.👌🏼

@whatever1617 10 лет назад

cysteine and tyrone are hydrophobic

@mygoldentruth 10 лет назад

Lehninger refers to cysteine as polar, thus hydrophilic. But yes, tyrosine is actually nonpolar as far as I know.

@jedbom5646 8 лет назад

Isn't Glycine hydrophilic and cysteine hydrophobic

@jsowels19 8 лет назад

+j edbom looked it up and no glycine is non polar and hydrophobic cysteine is neutral and hydrophilic

@NewtonMD 2 года назад

This is how to classify amino acids. Lol I can't memorize the actual 20 Amino acids

@ChompNom 6 лет назад

i really like the handwriting

@TrojansOwl1 7 лет назад

Haterz 😂

@taniaahmed705 4 года назад

👍

@jlg7561 6 лет назад

I was expecting to hear Sal :[

@RewanMho-zg8zw 3 месяца назад

من طرف محمود الصالح

@Karbonics123 7 лет назад

i nutted amino acids

@chainzss 5 лет назад

she sound cute af

@redwithstyle 6 лет назад

This video has an error. The amino acids that are basic are basic because the side chain Nitrogens have a lone pair that they can DONATE. It’s not willing to accept electrons and if it were it would be acidic.