Week 3: Day 2
The magic of conception!
This is directly out of my course reader from my Human Growth and Development class. I had to share this with you because it truly read like an epic story to me! I'm only sharing the first paragraph, but the rest of it gets into more detail. I'm including exclamation points where I feel they've been omitted, or other of my personal commentary in italics. ;)
"Sperm Transport and Capacitation"
Sperm travel a treacherous path as they propel themselves through the female reproductive tract. Millions of them leak from the vagina almost immediately after being deposited there. (!) Of those that remain, millions more are destroyed by the vagina's acidic environment and, unless the cervical mucus has been made fluid by estrogens, additional millions fail to make it through the cervix (so then when someone is not ovulating, there's a gate-keeper holding guard at the gate!). Those that do manage to enter the uterus are subjected to forceful uterine contractions that act in a "washing machine-like" manner to disperse them throughout the uterine cavity ("hang on guys, we're about to catapulted around this strange place!" says one sperm to the other). There, thousands of these dispersed sperm are destroyed by resident phagocytic leukocytes (just when you thought you were safe by making it past the cervix, more dudes are trying to kill you!). Is it estimated that only a few thousand (and sometimes fewer than 500) sperm, out of the millions in the male ejaculate, finally reach the uterine tubes, where the oocyte may be moving leisurely toward the uterus ("leisurely", really? The sperm have to deal with getting past a gate-keeper, a washing machine, and dudes trying to kill them, and the egg is just "hanging out" waiting to get fertilized? This makes it sound like the sperm do all the work!)
The end.
This is directly out of my course reader from my Human Growth and Development class. I had to share this with you because it truly read like an epic story to me! I'm only sharing the first paragraph, but the rest of it gets into more detail. I'm including exclamation points where I feel they've been omitted, or other of my personal commentary in italics. ;)
"Sperm Transport and Capacitation"
Sperm travel a treacherous path as they propel themselves through the female reproductive tract. Millions of them leak from the vagina almost immediately after being deposited there. (!) Of those that remain, millions more are destroyed by the vagina's acidic environment and, unless the cervical mucus has been made fluid by estrogens, additional millions fail to make it through the cervix (so then when someone is not ovulating, there's a gate-keeper holding guard at the gate!). Those that do manage to enter the uterus are subjected to forceful uterine contractions that act in a "washing machine-like" manner to disperse them throughout the uterine cavity ("hang on guys, we're about to catapulted around this strange place!" says one sperm to the other). There, thousands of these dispersed sperm are destroyed by resident phagocytic leukocytes (just when you thought you were safe by making it past the cervix, more dudes are trying to kill you!). Is it estimated that only a few thousand (and sometimes fewer than 500) sperm, out of the millions in the male ejaculate, finally reach the uterine tubes, where the oocyte may be moving leisurely toward the uterus ("leisurely", really? The sperm have to deal with getting past a gate-keeper, a washing machine, and dudes trying to kill them, and the egg is just "hanging out" waiting to get fertilized? This makes it sound like the sperm do all the work!)
The end.