The “moment” of fertilization?

acrosomerxn

What moment? Fertilization is a complex process, with a series of steps.

  • First, the sperm cell binds to the pellucid zone surrounding the egg. This is specific; sperm and egg have to recognize each other and bind appropriately. You don’t want the sperm to bind to every epithelial cell of the reproductive tract, after all, and you don’t want the egg cell to be receptive to every passing white blood cell.

  • This binding triggers the acrosome reaction. The tip of the sperm cell ruptures releasing enzymes that break down the glycoproteins surrounding the egg and exposing the sperm cell membrane and the egg cell membrane locally.

  • Those two membranes then fuse, and the sperm cell nucleus is drawn into the cortex of the egg. This is called docking and invagination.

  • Docking triggers a wave of electrical activity in the egg cell membrane; from the point of entry, a ring of depolarization sweeps rapidly across the egg, causing vesicles to fuse and dump their contents into the space surrounding the egg, creating a barrier to additional sperm trying to enter. This can be visualized using chromophores that change color in response to membrane voltage, or that react to the binding of calcium, the important ion that crosses the membrane at this step.

  • The germinal vesicles, or nuclei, of sperm and egg then move via cytoskeletal transport towards each other and fuse to create a single diploid nucleus.

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I have not seen or heard #lemonade

I am a sociocultural failure, I know. But I don’t have a subscription to either HBO or Tidal, so all I’ve got are tiny snippets. One thing I’ve heard more of is the strident yodeling about “Becky”, which is nicely explained on VSB. It’s telling, as well, that there is more irritation about a brief remark that is perceived as a slight against white people than several centuries of ongoing oppression of black people.

It also reminds me of something I experienced a few times when I worked at Temple University. There were a couple of occasions when the subway and trains were out of service, and I had to walk home to the northern suburbs…which meant strolling through North Philadelphia, which is a rough neighborhood, poor and neglected. I am a white professorial looking dude. I didn’t fit in. I startled a few people, I know, who were curious about me, and they’d ask. And that’s where the worst thing that happened to me in a black neighborhood occurred.

They all called me “Bob”.

Maybe it’s just a North Philly thing, but apparently the stereotypical white person is named “Bob”. I can sort of see it, I guess.

But otherwise, you know, I was unconcerned. I was walking through black communities, which are no more supportive of muggings or robberies than the white communities I was walking towards. And I could not get outraged at the trivial thing about a stereotypical name, because, as VSB explains…

There are two schools of thought on what qualifies something as racist. The first is that something is racist if the act stems from either a belief of racial superiority or a position of constructed/structural racial superiority. (Or both.) The second encompasses all unfavorable acts which might be race-based. Basically, one school of thought is right (the former) and one is wrong (the latter).

I agree, the first definition is the right one. “Becky” or “Bob” are not a danger to anyone. So why is that what so many people are concerned about?

And I know, I’ve got to find a way to watch Lemonade.

#VoteBlueNoMatterWho

I am not happy to see Sanders sliding further away from the nomination — and I am not enthusiastic about Clinton. But I have to agree with George Takei.

I am not saying that Sanders should surrender — he should keep fighting for his cause as long as possible, and he should be doing his damnedest to shape the party platform (and maybe, as hope keeps whispering in my ear, maybe he’ll make a miraculous victory), but we have to focus on crushing the Republican party in all branches of government, and also on keeping the pressure on a certain conservative Democrat who is likely to be the nominee.

Cruz picks Fiorina for VP?

What is he thinking? This is an act of desperation, but I don’t get what she brings to the ticket. It’s as if he went looking for an unpleasant, unpopular person to complement his own unpopular unpleasantness. Or maybe he thinks McCain set a precedent.

Sure, it’ll bring more attention to his campaign, but it’s the kind of attention dog poop on a sidewalk brings — you make sure not to step in it.

Creationists and pterosaurs

fathersonpterosaur

Of course they don’t understand the science, and they don’t understand the history, either. The Institute for Creation Research makes an utter botch of the history of our knowledge of pterosaurs, arguing that because scientists have a different view of flying reptiles now than we did when they were first discovered, evolutionists have been getting it wrong all along.

Dave Hone explains why they’re wrong. For one thing, the first pterosaur fossils were found in the 18th century, before Darwin, so it’s kind of silly to pin the errors of interpretation on evolutionists — there weren’t any around. I’d also say it’s rather typical that it takes time and much research to establish an accurate interpretation, so basically this is a case where the creationist is complaining because scientific knowledge progresses.

But another thing leapt out at me in the ICR article.

The evolutionary timeline fails to match the most obvious pterosaur fossil data, but Genesis history readily explains them. First, pterosaur structure was flight-ready from the get-go because God created it to be. Second, a terrible, watery cataclysm like Noah’s Flood buried these winged creatures—often in the same layer as dinosaurs, fish, lizards, small mammals, and birds—leaving behind elegant, fully formed pterosaur fossils with no evidence that intermediary “also-ran” versions ever existed.

Oh, really? Pterosaurs are in the Bible? I don’t think so.

I also note the dishonest elision at the end, that pterosaurs are found in the same “layer” as small mammals. This is true. But these are not the small mammals we are familiar with — no squirrels, no mice, no voles or moles.

It’s all just wall-to-wall lies.

Carrie Poppy reads Of Pandas and People, so you don’t have to

pandas

Really, you don’t want to ever have to bother reading Of Pandas and People: The Central Question of Biological Origins, the terrible textbook from the Discovery Institute that was at the heart of the Dover trial. It’s badly written sludge, warmed over creationism (remember “cdesign proponentsists”, the typo that was the result of a botched copy/replace of “design proponents” for “creationists”? That was from this book), and it’s basically an error-filled bad textbook.

Carrie Poppy read it for the Center for Inquiry. I don’t know why. Maybe the editors were playing a cruel trick, like saying “here’s a flashlight and a shovel; I need you to do an important investigative piece exploring my cesspool”, but she survived and has written a brief summary of a few things that leapt out at a lay person reading a pseudoscientific text. It’s entertaining.

But come to think of it, my bathroom sink is clogged. I’m sure there’s a story in it. I wonder if Carrie would like to stop by and venture into the world of old toothpaste, hair, and drainage?

By the way, I also talked about Pandas and the Dover trial in my intro class on Monday. It’s important to remember the ugly bits of history so we don’t repeat them.

Diseased puppies taint the Hugos again

spaceraptor

The Hugo Award shortlist is out, and it has some good stuff on it. In the best novel category, I’m torn between Ancillary Mercy (that whole series has been a revelation) and The Fifth Season, while among the novellas I’ve been generally impressed with Nnedi Okorafor, who has been waking me up to a fresh perspective.

So there’s no shortage of good writing in the list, but at the same time, the Rabid Puppies have injected a lot of crap in there, too. It’s as if they can’t make up their minds: do they want to build credibility by nominating already popular works, taking credit for promoting well-written material, as Scalzi points out, or do they want to make a mockery of the whole process, since they know they’re not going to win? It’s a weird game they’re trying to play.

So they simultaneously promoted a Neil Gaiman graphic story, and a Chuck Tingle short story. Which is it going to be, guys? Are you making a play to see your point of view seriously represented, or are you just playing games with the nominations?

I think the joker strategy won out, given the large number of nominations from the publisher Castalia House, Vox Day’s little dreck mill. I wonder when they’re going to give Chuck Tingle a contract?


Bonus! I can read Space Raptor Butt Invasion for free through Kindle Unlimited, so I ordered a copy. Look what Amazon tells me are recommended now, based on that purchase: John Wright and Vox Day. Such perfect bedfellows.

spaceraptorbuttinvasion

No, not Ian McEwan!

BloodTypes

I love his books. But there he goes, getting all naive and narrow:

Novelist Ian McEwan recently summed up the impulse to see two categories: “Call me old-fashioned,” he told an audience, “but I tend to think of people with penises as men.”

I’m 9 years younger than McEwan, which I guess makes me one of those young whippersnappers. I’m still kind of peeved at this tendency to ascribe certain regressive views to entire generations, as if old people get excused from simple humanity, and are all done with learning and growing. I’m not planning on turning into a simple-minded fool in the next few years (not that it can’t happen!).

But right now I can say I don’t think like Ian McEwan.

I tend not to think about people’s penises, or lack thereof.

I’ve met thousands of people, and so far, none of them have introduced themselves by showing me their genitals. I don’t think that would be a particularly helpful revelation, anyway; I’ve found a bit of conversation to be far more revealing.

I tend not to characterize people into one of two groups by the degree of enlargement of their embryonic genital tubercle, either. That seems a kind of crude and useless taxonomy. In general, lumping humanity into men on one side and women on the other seems like a useless distinction that ignores a tremendous amount of nuance.

I’m going to start thinking of people in terms of their blood groups. I really should start hanging out with more type O people, in case there is a tragic accident and I need a transfusion. I’m incompatible with those A and B people, and those ABs, just forget it. But at least I’ve divided humanity into four arbitrary subsets, rather than a mere two.

Call me old-fashioned, but I tend to think of type O people as potential blood donors.

That’s not dehumanizing, is it?

Suppressive Persons

ruthless

The Church of Scientology is to be blessed with interesting times. The father of David Miscavage, head of the church, is publishing a tell-all book next week, titled Ruthless: Scientology, My Son David Miscavige, and Me. Well, they plan to, anyway — David Miscavage is threatening to sue for defamation if they go through with it. That’s the best advertisement ever. It must be really juicy, although I can’t say I look forward to reading about the childhood of a psychopath.

That the religion would tear apart families is no surprise. Like many cults, they have a policy of disconnection: new converts are told to sever all ties with family members who might weaken the influence of the church on them. The church becomes a collection of deeply unhappy people who have no choice but to rely on each other.

Scientology is to be featured on 20/20 this Friday. Man, it’s hard to be a secretive evil organization when people keep shining a spotlight on you.

And they’re shedding celebrities! Lisa Marie Presley has become disaffected and is dishing dirt behind the scenes. Could it be that we’ll see a religion die in our lifetimes? That would be nice.