Meiosis 1 | Crossing over and Phase identification

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Күн бұрын

This video covers the first phase of meiosis in detail. We look at each phase, its purpose and how to correctly identify it. The similarities as well as differences between mitosis and meiosis are also explained. The second stage of meiosis is covered in a separate video.
Table of contents
Revision of mitosis 00:00
Interphase 02:02
Prophase 1 05:01
Crossing over 10:10
Metaphase 1 12:08
Anaphase 1 15:23
Telophase 118:02
Terminology recap 20:55

Пікірлер: 49

@akshaysewpersadh8425 3 жыл бұрын

I was the boy that requested the video madam , thanks again really informative 😁❤

@taylabritz 8 ай бұрын

last minute revision for finals is the BEST with your videos, thank you for doing what you do, you're an angel 🖤

@AyangaNgombane 8 ай бұрын

Right

@katM469 8 ай бұрын

Past exam questions is the only way you'll pass

@dorisdiribe 2 жыл бұрын

This is so detailed and helpful, thank you ma! Please don't stop making videos, it's has helped me a lot.

@meganmaree0903 3 жыл бұрын

I’m writing my Term 1 Bio exam tomorrow. Thank you so much for this!!

@banokuhle9293 Жыл бұрын

You honestly deserve the world hey

@19langman 3 жыл бұрын

Thank you so much this is honestly done so well, love your stuff

@khumonthabeleng3326 Жыл бұрын

I have a question..doesn't cytokinesis appear in anaphase 1 and on my notes ,I came upon a word "allele" what's that?

@sumaalexander6836 3 жыл бұрын

your lecture is is precise and informative. Could you pls take a video on Iheritance and Genetics --Pedigree charts.

@user-kn6mi2th4m 5 ай бұрын

thank you ma ! ❤ i am writin a topic test tomorrow

@fafiali7080 2 жыл бұрын

You are such a brilliant teacher 👏❤

@tamimalopes3495 2 жыл бұрын

Thank you ❤️

@owamialicia2674 3 жыл бұрын

Thank you.❤❤

@David_Dingani 2 жыл бұрын

Thank you so much ma'am

@LaraDarb 7 ай бұрын

Thank you sooooo much ❤❤❤❤❤

@movies-mt4so 3 жыл бұрын

Thank u 🤩

@sazidlamini8453 Жыл бұрын

thank you😍😍

@tebellomoqolo5969 2 жыл бұрын

Thank you mam😰

@gamerboys2458 3 жыл бұрын

Ive came from Tik tok

@jasminehasan7084 2 жыл бұрын

I have a question---after meiosis 1 when you have two unique daughter cells are they diploid or haploid? And how can I easily identify diploid vs haploid? I tend to get confused with those. Thank you!

@missangler 2 жыл бұрын

They are haploid. The only way to identify them is knowing the original amount of chromosomes which they often tell you. Another way is to look for homologous pairs being separated or when the chromatids have separated.

@jasminehasan7084 2 жыл бұрын

@@missangler Thank you so so much!

@emilybates2255 3 жыл бұрын

Thank you for the video ma'am. I am a bit confused that DNA replication occurs in interphase before Meiosis 1 begins just as Mitosis does. How does Meiosis 1 form a haploid number of chromosomes in the 2 unidentical daughter cells. In diagrams for mitosis the centromeres of the chromosomes split and are pulled apart but because of replication each daughter cell has a diploid number of chromosomes but in Meiosis 1 the whole recombinant chromosomes are pulled apart forming the two unidentical daughter cells with a haploid number which then go through Meiosis 2 without replication and form 2 more unidentical haploid cells. I feel I'm missing something...

@missangler 3 жыл бұрын

Hi Emily so you are right both mitosis and meiosis use DNA replication to double the amount of chromatids. In mitosis we separate the chromatids by the centromere. In meiosis 1 we separate the homologous pairs first (which halves the chromosome number) then we in meiosis 2 we separate the chromatids. Keeping the haploid number just maintaining the haploid single stranded chromosomes

@misskija 3 жыл бұрын

damn you really saving me 😂

@siphesihlemohlapa Жыл бұрын

and also is it wrong for me to mention the process of synapsis because my teacher said it was wiped out of the curriculum I always mention it and I feel like am going to get marked incorrect

@missangler Жыл бұрын

At the end of the year exams its still accepted so your teacher should still accept it. ( I am a senior marker at the end of the year so I do have experience on this)

@siphesihlemohlapa Жыл бұрын

I am confused about how many cells we are going to end up with after meiosis and how many cells we going to end having in meiosis 2

@missangler Жыл бұрын

End of meiosis 1 you have 2 haploid cells. The chromosomes still have a centromere so in Meiosis 2 we need to separate them. At the end of meiosis 2 we will take those two cells, divided them again and get 4 non-identical cells that are haploid. You have now separated the centromeres for single stranded chromosomes.

@imanallie8111 Жыл бұрын

Ms , I’m in class 2023, and they mentioned that the word “bivalent” is not allowed anymore ? Is that true and what is the word replacing it ?

@missangler Жыл бұрын

The truth is the word is still applicable but most pupils don't use it correctly. I still use it when I teach my children. I am a senior marker at the end of the year exams and I still accept it.

@user-go3dy2nr6b 4 ай бұрын

what is the difference between a chiasma and bivalents

@IamBipolarSunshine06 4 ай бұрын

Chiasma/chiasmata is a point where the homologous pair touch each other during crossing over whereas bivalents are the chromosomes during/after crossing over. They are called bivalents during crossing over or after it . Not sure if you quite understand or

@user-sb8pb9kp4k 4 ай бұрын

Where to go your cheatsheet grade 12 life science

@naledimaimela Жыл бұрын

Mam can u pls make a video about the process non disjunction

@missangler Жыл бұрын

I already have on up called abnormal meiosis

@Matric-ov4gr 3 жыл бұрын

I'm first.♥️♥️♥️

@itsgenevagomes Жыл бұрын

Hey Miss Angler! I trust that you’re well 🤍 question: could we say that a homologous chromosome is a pair of chromosomes that carry corresponding genetic* information?

@missangler Жыл бұрын

Yes you can

@_undeniably_blessed_33 4 ай бұрын

Ma'am in class we were told there is no interphase in meiosis

@IamBipolarSunshine06 4 ай бұрын

Interphase is a phase that occurs prior meiosis. That's why Ms Angler explained it so that we can be able to understand what happens BEFORE prophase 1 and explain it if we're examined on that