Cellfie Life

**This episode contains sexual health material**

Let's talk about sex, baby! Let's talk about you and me…or let's talk about reproductive systems, and hormones, and the anterior pituitary, and the endometrium, and the epididymis.

Welcome to the Cellfie Life. Thank you so much for listening. If you have questions or comments, or corrections, please let me know. The best way to reach me is either the website CellfieLife.com or on Insta at @thiscellfielife.

On the website, I have the script notes from all the episodes. So if you want to print out and use them to aid in your studying, the transcripts are available under the episodes. And follow me on Insta! I post MCAT prep questions on my story every morning, and I will let you know when a new episode drops, but if you subscribe, they will be automatically downloaded for your listening pleasure. And tell your friends about this podcast. As a non-traditional premed, I decided to make this podcast because I couldn't find an MCAT review podcast, and I really wanted one. So now that I am making it, I want other premed students that are out there hustling and busy—like you all are—to have this as an added resource for your test prep.

This episode does have sexual health material—so this is your warning: We're gonna be talking about penises and vaginas.

And one last note before we jump in: This episode is about biological sex, not necessarily gender expression or gender identity.

Anyway, let's get down…to business, that is, and the reproductive system.

You guys, I'm gonna try not to do a ton of sex puns, but as I was writing this episode, everything sounded like a sexual innuendo. Sorry, not sorry

Okay!

The reproductive system includes sex organs and parts of our brains. We are going to start with males because they are easy.

In my opinion, male reproductive systems and hormones are pretty straightforward, so we are going to start with males and then graduate up to females.

Along with what we usually think of as reproduction duties—creating sperm and eggs—the reproductive system is also responsible for producing hormones. Because these hormones come from our reproductive system, they are dubbed our "sex" hormones.

Sex starts in the brain.

The sex organs are controlled by the brain, specifically the hypothalamus and anterior pituitary. The hypothalamus is really important. I think of the hypothalamus as an air traffic controller. The air traffic controller sits up in the tower and watches everything that is going on. If a plane is taking a long time on the landing strip, the air traffic controller tells the incoming plane to hang on before it lands so that there is not a crash. The hypothalamus does the same thing. It sits up in the brain and monitors what is going on in the body and gives directions if it sees that something is straying too far from homeostasis.

The hypothalamus regulates body temperature, appetite, physiological cycles, and sexual behavior, to name a few. We will talk more in detail about the hypothalamus later, but I wanted to introduce it because it has a really important role in homeostasis and, thus, health. But right now, we'll just talk about the hypothalamus's role in regards to the reproductive system.

The hypothalamus is bossy, just like a good air traffic controller. You don't want an air traffic controller that waffles back and forth about whether a runway is clear for a plane to land.

Hello, and welcome to the Cell-fie Life. Thank you so much for listening! My name is Nikaela and today we are going to be reviewing the cell cycle, meiosis, and mitosis.

If you have questions or comments or corrections, please let me know—the best way to reach me is on Instagram with the handle “thiscellfielife”. That’s this C-E-L-L-fie Life.

Also, if you follow me

on Instagram, I post MCAT prep questions on my story every morning, I hold

giveaways, and I will let you know when new episodes drop.

Please rate, review, and

subscribe. And tell your friends about this podcast. The entire reason I

decided to do it is because I wanted to be able to listen and study while

working, driving, and doing house chores. I didn’t find a podcast that was

providing what I wanted, so I decided to create one. Share with your study

buddies!

Okay, let’s do

this—mitosis and meiosis.

There are two main types

of cell division that we humans take part in: mitosis and meiosis.

Mitosis is the process

of making new body cells, so it is how two identical daughter cells are created

from a single cell.

Meiosis is the type of

cell division that creates gametes, eggs, and sperm. Meiosis results in up to

four non-identical daughter cells.

When I first learned about mitosis and meiosis, I could not keep their names straight. Which one happens in somatic cells and which one creates germ cells? And, because in science we like to name things very similar to one another to make things extra fun—just wait till we get to centromeres, centrosomes, centrioles, and kinetochores, and we will get to those—I had to think of a clever (or dumb) way to remember which one was mitosis and which one was meiosis.

And, let’s be honest, I

went with the dumbest and most ridiculous way to remember: Have you guys ever

seen the movie Singing in the Rain? There is a song that has the line,

“Moses supposes his toeses are roses, but Moses supposes erroneously...”

And for some reason, I combined “Moses” and “toeses” when I was singing, and it came out “Mos-toesis, and from there it is a really was a short leap to: “Mitosis happens in the toeses”.

If mitosis is happening

in your “toeses”, well, your toes do not need to create sex cells—your toes are

somatic cells. In somatic cells, mitosis is what occurs to create genetically

identical diploid daughter cells.

So if mitosis is

creating somatic cells, then meiosis is happening in germ cells . If my

“Singing in the Rain” song wasn't enough to help you keep mitosis and meiosis

straight meiOOOsis happens in your ovaries—or, you know, testes, if you

are male.

If you guys want to check out the song I’m talking about, “Singing in the Rain”, I’ll post the YouTube clip on the website cellfielife.com. There is also some excellent tap dancing, you know if that’s your thing. To see the whole thing, here’s the YouTube link:

https://www.youtube.com/watch?v=zFAlZttXfvE

So now that you will

never switch up the location of mitosis and meiosis, let's get into the

nitty-gritty:

A lot of people approach the cell cycle with a pie chart, which is great—I love pie. And I'm willing to bet that a lot of you have seen this breakdown. I’ll post it on my Insta and on the website, but I'm going to approach the cell cycle,

Cell-fie Life is an educational podcast reviewing topics covered by the Medical College Admissions Test (MCAT).