How did y'all understand mitosis/meiosis in intro college bio?

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nad7vx

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I am taking intro bio and we are currently learning about mitosis and meiosis. although i understand the general process, I find myself getting really mixed up with the terminology (i.e: homologous chromosomes, sister chromatids, non-sister chromatids) and find it really hard to keep track of what is happening where and when.

I was wondering if any of guys with experience tell me of ways that helped you understand mitosis and meiosis better? thanks

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We just took our test on cell respiration, mitosis, and photosynthesis Damon 2 other chapters. I just do our homework, study our PowerPoints. But I'd highly recommend you check out khan academy....has every subject but I've been using them/him for chemistry biology and have found it extremely helpful

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I am taking intro bio and we are currently learning about mitosis and meiosis. although i understand the general process, I find myself getting really mixed up with the terminology (i.e: homologous chromosomes, sister chromatids, non-sister chromatids) and find it really hard to keep track of what is happening where and when.

I was wondering if any of guys with experience tell me of ways that helped you understand mitosis and meiosis better? thanks

SDN isn't for homework help, however, making flashcards is your best bet, was for my friends and myself.
 
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i'm not asking for homework help. I was seeking studying methods, which I am sure is one of the things SDN helps out with.

and thank you about the khan academy, i'll check that out.

Any other methods?
 
I was wondering if any of guys with experience tell me of ways that helped you understand mitosis and meiosis better? thanks

When I was taking Honors Bio in high school, the first thing I would do after getting home each day is try to draw and label the diagram in the textbook from memory. Then I would open up and check my drawing against the textbook's. If I got anything wrong, I would close the book and try again. Rinse and repeat until the diagram is 100% right. Simple, but effective.
 
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Hahahaha when you figure it out, will you let me know? I've gone through that material at least ten times for different classes and *still* don't have it down 🙂
 
I am taking intro bio and we are currently learning about mitosis and meiosis. although i understand the general process, I find myself getting really mixed up with the terminology (i.e: homologous chromosomes, sister chromatids, non-sister chromatids) and find it really hard to keep track of what is happening where and when.

I was wondering if any of guys with experience tell me of ways that helped you understand mitosis and meiosis better? thanks
I remember ME-iosis because I like sex ("me like sex)= sexual reproduction...so the other have to be somatic cells... Im very serious so dont judge me. Homologs and chromatids has just clicked with me. So no perverted tricks to them🙁.
 
Kinda trite but I'm learning mitosis and meiosis well simply by reading the textbook and I'm also drawing the mitosis and meiosis process and identifying the different structures on paper for practice so that's definitely helping me remember the steps and little details.
 
Kinda trite but I'm learning mitosis and meiosis well simply by reading the textbook and I'm also drawing the mitosis and meiosis process and identifying the different structures on paper for practice so that's definitely helping me remember the steps and little details.

Once I learned how the centrosomes and kinetechores positioned and when they dissolve the nuclear envelope/how they line up the chromatids I found it extremely simple.

Just now doing Meiosis but I can't imagine it any more difficult.
 
What helped me was to draw each step of the process, and the chromosomes/chromatids in each cell.

Some things to remember:

1.) count chromosome number by counting the number of centromeres

2.) look at a karyotype- there are 23 different chromosomes (labeled by number, biggest- sized chromosome to smallest), but one from mom and one from dad, giving each somatic cell 46 chromosomes total

3.) look at the cell after replication- each of those 46 chromosomes will have replicated to give you 4 individual chromatids for each numbered chromosome (I.e. Chromosome 13 will have 4 chromatids- 2 from mom, and 2 from dad). The X shapes are the linked chromatids ( I.e. Chromosome 13 will have 2 X shapes - one X is mom's chromosome 13 replication, the other X is dad's chromosome 13
replicated).


4.) after replication, even though there are 4 chromatids for each of the 23 numbered chromosomes, there are still only 46 chromosomes. That's because you're counting chromosome number by counting centromeres, and as 2 sister chromatids (the 2 lines in the X shapes) are linked, they only count as 1 chromosome.

5.) you'll never have 92 chromosomes in a normal cell

6.) meiosis is the separation of homologous chromosome. This means, for chromosome number 13, mom's two linked chromatids( the X shape) are going to separate from dad's two linked chromatids ( other X shape). By the end of Meiosis 1, two cells will have formed, one with mom's X, one with dad's X.

7.) in mitosis, the two lines of 1 X shape are going to separate.

Don't know how much sense that makes, I would google for some pictures.
 
My tip would be to study each separately, to reduce confusion. Study one concept completely, take a break and than study the other concept.
 
I learned it best drawing diagrams on the school's whiteboards in the study rooms
 
Tbh I didn't learn it completely correctly until genetics. But basically I learned it by drawing it out with simpler karotypes, i.e I drew out both things with a cell with 4 chromosomes. Do it enough times, counts the numbers, and you'll get it down.
 
thanks for the replies guys. I was wondering if someone can correct me on my chromosome count:

During mitosis in human cells, we start out with 46 chromosomes and after S-phase we have 46 chromosomes, however, each chromosome is replicated and is called a sister chromatid. Then at the end of mitosis we split apart these sister chromatids, therefore each daughter cells gets 46 chromosomes.

During meiosis in human cells, we start out with 46 chromomses and after S-phase we have 46 chromosomes (as sister chromatids). Then during prophase, we have crossing over and synapsis. Therefore, we have 23 tetrads. During meiosis I, we separate the tetrads. So the 2 daughter cells at the end of meiosis I have 23 sister chromatids in each of the cells. Then during meiosis II, the 23 sister chromatids separate into 4 daughter cells, each containing 23 chromosmes. Therefore, during meiosis we start out with 46 chromosmes and end up with 4 daughter cells with 23.

Did i get that all right? or did the mess up my thought? any help would be great
 
I'm not gonna lie the terminology really confused me in the beginning as well. Once you understand the terminology it's really easy.

One way to remember mitosis: PMAT (Prophate, Metaphase, Anaphase, Telophase).
As far as the terminology goes.. google the definitions and compare them to each other & eventually it'll make sense.
 
thanks for the replies guys. I was wondering if someone can correct me on my chromosome count:

During mitosis in human cells, we start out with 46 chromosomes and after S-phase we have 46 chromosomes, however, each chromosome is replicated and is called a sister chromatid. Then at the end of mitosis we split apart these sister chromatids, therefore each daughter cells gets 46 chromosomes.

During meiosis in human cells, we start out with 46 chromomses and after S-phase we have 46 chromosomes (as sister chromatids). Then during prophase, we have crossing over and synapsis. Therefore, we have 23 tetrads. During meiosis I, we separate the tetrads. So the 2 daughter cells at the end of meiosis I have 23 sister chromatids in each of the cells. Then during meiosis II, the 23 sister chromatids separate into 4 daughter cells, each containing 23 chromosmes. Therefore, during meiosis we start out with 46 chromosmes and end up with 4 daughter cells with 23.

Did i get that all right? or did the mess up my thought? any help would be great

after meiosis I there are 23 chromosomes/cell, 46 sister chromatids total per cell. meiosis II you have 23 chromosomes, 23 chromatids per cell.

It also might help to think ploidy rather than the total number of chromosomes. Also there is another parameter that reflects the absolute amount of chomosome material so for S you have ploidy stay at 2 but this value goes from 2->4. Again im sorry i forget what it is, but i think it would be helpful to track these values through each process (then whatever n equals in the organism you can get to chromosome value stuff)

Edit: I believe the value that reflects the absolute chromatid material is the c-value.
 
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Mitosis = TOE = body cell
Meiosis = SEXY TIME = sex cells

That's all you need to know, right? 😉
 
Using chromosome finger puppets working my way through the various stages of mitosis/meiosis in the air helps.

1 finger = Chromosome
2 fingers (genetic material of a chromosome has duplicated in S phase) = sister chromatids of a single chromosome, joined at the knuckle (centromere.)
The number of centromeres present is equivalent to the number of chromosomes present (at least in my limited understanding.) Don't get confused just because there are two chromatids corresponding to the same chromosome joined together. 1 centromere joining the sister chromatids = 1 chromosome.

In prophase I of meiosis, there is crossing over of the nonsister chromatids of homologous chromosomes... using "chromosome finger puppets," hold up the index and middle fingers of both hands, and join the index fingers of both hands. It will make a w or h depending on how you look at it. H is for homologous chromosomes. The remaining middle fingers are flicking off the crossed non-sister chromatids for intermingling their genetic information. Those scurrilous fornicators - how dare they intermingle?

I dunno. I looked like an idiot doing the whole chromosomal finger puppet thing on my test, but it works for me. :laugh:
 
Using chromosome finger puppets working my way through the various stages of mitosis/meiosis in the air helps.

1 finger = Chromosome
2 fingers (genetic material of a chromosome has duplicated in S phase) = sister chromatids of a single chromosome, joined at the knuckle (centromere.)
The number of centromeres present is equivalent to the number of chromosomes present (at least in my limited understanding.) Don't get confused just because there are two chromatids corresponding to the same chromosome joined together. 1 centromere joining the sister chromatids = 1 chromosome.

In prophase I of meiosis, there is crossing over of the nonsister chromatids of homologous chromosomes... using "chromosome finger puppets," hold up the index and middle fingers of both hands, and join the index fingers of both hands. It will make a w or h depending on how you look at it. H is for homologous chromosomes. The remaining middle fingers are flicking off the crossed non-sister chromatids for intermingling their genetic information. Those scurrilous fornicators - how dare they intermingle?

I dunno. I looked like an idiot doing the whole chromosomal finger puppet thing on my test, but it works for me. :laugh:

Who cares if you look like an idiot if you get the questions right? 👍 I learned the finger thing too my freshman year. I taught Intro to Bio lab my junior and senior year and taught it to my students - got tons of feedback saying it was a huge help.
 
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