Egg, sperm, and fertilization | Behavior | MCAT | Khan Academy

Created by Jeff Otjen.

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[mandyads]

Start video at 4:46 if you only need the detailed info about the actual fertilization process... Only if you already know the in's and out's of the sperm and the egg!

[hollie]

I’ve been a midwifery student since September, have my first A&P exam next month. Terrified because I feel like I’ve learnt nothing. Spent an hour watching videos this morning and have felt a sense of absolute relief. Thank you SO much

[priscillalow]

the zona pellucida you labeled is corona radiata. zona pellucida is only the thin membrane you draw below the corona radiata.

[fashionfreak]

just to reiterate Priscilla Low - the zona pellucida is a thin membrane below the corona radiata - please  could you amend this on the video with an annotation thank you!

[officialjoshuachristian]

This was the only video that could clearly answer my question as to why only ONE of the 200 million sperm cells released into the female is fertilized and the others don't. Thank you sm! :)

[shruthitella]

please make a much detailed and a correct video about sperm entry and the reaction plzz

[douglasgillarddcprofessoro]

This is not very accurate. For example, completely forgot to mention the corona radiata. The acrosome is more like a football helmet which surrounds the sperm plasma membrane and head. Also forgot to mention that none of this can happen without the sperm going through the process of capacitation. Again, I wouldn't study this if you're in graduate school.

[rrk]

For all those complaining about the video not being detailed enough, there are other more detailed videos out there. This happens to be perfect for my extremely dumbed down intro bio course, and covers exactly what I need without giving me terms and specs I dont need to know

[syonathomas]

At 4:09, "Now remember the egg cell had 75 to 100 big mitochondria..."
I think you mean the "sperm cell".

[ankita]

good video bt info must be more in detail.

[emilye]

This is great and easy to understand but incomplete.

[alef_]

maybe that is the zona pellucida, but he did not put the corona radiata

[pegeepriyanka]

awesome...can u provide more detailed videos on cleavage and gastrulation of c.elegans, zebra fish, xenopus and chick..and organogenesis of chick embryo....?

[nenitababbygirl]

Hi there all the information you provided is great but I would like to know about basal body temperature what role play the temperature during the 28th day cycle when rise up and when and why goes down. Can you pleas school me on that topic thank you

[aHebrewMidwife]

I think this video is confusing the zona pellucida with the corona radiata. The corona radiata is the outermost layer of the oocyte that the acrosomal layer of the sperm disperses in order to reach the zona pellucida.

[NatashaAmin]

at about 4:07 there is a little verbal mistake where mentioning how many mitochondria the sperm cell consists of (70-100), the author says "egg cell". I don't believe it'll trip anyone up too badly but it could be something to note

[ArtemRomanov]

With what frequency do cortical granules check for sperm invasion?

[amandev]

fertilizin - anti fertilizin reaction?

[jerichorhodesalambatin]

well explained sir. thank you so much. i just have a question. is a single sperm or a single egg cell (not fertilized) already considered human? also are red blood cells or liver cells and what not in the human body considered human? i just wonder really sir about the answer basing on the definition of being a human organism or being a human cell. hoping for your rep. thanks so much

[sigrunkatrin]

There is no debate about the mitochondrial DNA coming only from the mother.