Note (12/2015): Hi there! I'm taking some time off here to focus on other projects for a bit. As of October 2016, those other projects include a science book series for kids titled Things That Make You Go Yuck! -- available at Barnes and Noble, Amazon and (hopefully) a bookstore near you!

Co-author Jenn Dlugos and I are also doing some extremely ridiculous things over at Drinkstorm Studios, including our award-winning webseries, Magicland.

There are also a full 100 posts right here in the archives, and feel free to drop me a line at with comments, suggestions or wacky cold fusion ideas. Cheers!

· Categories: Biology
What I’ve Learned:

Quiescence: how much less growth could there be? None. None less growth.
Quiescence: how much less growth could there be? None. None less growth.

Isaac Newton said a body at rest tends to stay at rest. That’s the First Law of Motion.

My mother said a body at rest had better tend to get his lazy teenage ass off the couch and mow the lawn before his father gets home, if he knows what’s good for him. I’m not sure that’s a “law” of anything, but it always got me moving. Eventually.

Inside your body are trillions of cells, and right now many of those are also at rest, in a state known as quiescence. What they tend to do next depends on what sort of cells they are, and how they got into that state to begin with.

Like teenagers, most cells go through phases. But instead of “goth skateboarder” or “sparkly vampire”, your cells go through phases of the cell cycle. The cell cycle is a set of steps cells go through to divide, because reproducing requires very careful planning.

If a cell went through the division process without a roadmap, anything could happen. It could split before it’s ready, and produce deflated Whoopie cushion cells that aren’t helping anyone. It could get its DNA scrambled, and serve it to the daughter cells, family-style. Or it could divide into fourteen cells at once, none quite the way they should be. Like Duggars. It’s terrifying. Thank goodness for the cell cycle.

But a cell’s life isn’t all spent thinking about reproducing. This isn’t college. Sometimes, cells need to exit the rat race of dividing over and over, and rest in quiescence. Take heart muscle cells, for instance. Once your heart has grown to full size during development, you don’t want it getting any larger.

(I know people like to think they have a “big heart”. But if it were big enough to squish your lungs between your ribs, you might reconsider that goal.)

To keep your heart from growing three sizes each day, the mature muscle cells are pulled out of the cell cycle right after a division, in a phase called G1. The “G” stands for “growth”, which is what cells typically do after dividing, but quiescence is a resting state, sometimes called phase G0. Because there’s no growth. Or dividing. Or anything else. The cells just sit there, doing their thing. Pumping blood, keeping you alive and leaving all the worrying about reproducing to you. If you’re into that kind of thing.

This also happens with neurons and other cells that stop growing after development; they enter quiescence, and basically never come out. But other cells can slip into the G0 phase from G1, for just a little post-division breather. Think of it as microscopic maternity leave.

Except that once cells divide, there’s no “parent” cell left. So really, it’s the children who were just produced that get a rest. Lazy kids. That grass is never getting mowed.

These “paused” cells — and in theory, any cells — can be pulled out of quiescence under the right set of circumstances. That could be a growth factor released in the body, or some other growth-goosing signal. Or maybe there are little mothers running through our bloodstreams, telling cells to get busy and do their chores.

The textbooks are silent on that last one. But sometimes, it’s the only thing that works. You do not want to be in the quiescence phase when your father gets home.

Image sources: University of Texas (cell cycle circle), Unilad (lazy, lazy teen), Mom This Mom That (Grinchy heart growth), Life as a Divorced Dad (quiescent kid, uncut grass)

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· Categories: Biology
What I’ve Learned:

Tumor suppressor: I'm no hero; I'm just doing my job.
“Tumor suppressor: I’m no hero; I’m just doing my job.”

Fighting evil isn’t all it’s cracked up to be.

First of all, it’s hard. Evil is basically everywhere outside of Walt Disney World, so there’s always another battle on hand. Also, evil is fiendishly creative. Just when you think you have it in check, it’ll pop up behind you, tenting its fingers and snarling, “Excellent.”

But the worst part about fighting evil is that you’ll never be recognized for anything else. That must get old for heroes. Sure, Captain America gets medals for thwarting villains — but maybe he writes poetry, too. Nobody talks about that. What if Superman is a great baker? Or Wonder Woman is a two-handicap golfer? Who would even know?

That’s how it is for so-called tumor suppressor genes. These are genes that have perfectly useful functions in normal cells, merrily toiling along, getting their jobs done. But nobody cares about those jobs — outside geneticists, who nose around everything a cell does. Instead, most people focus on one thing:

If these genes are knocked out of a cell — silenced by mutation or deletion or runaway genetic regulation — then the cell may turn cancerous. With tumor suppressors around, no cancer. Without them — watch out.

The thing is, these genes don’t exist to prevent cancer, exactly; the very name “tumor suppressor” is misleading. In their mild-mannered day jobs, these genes get translated into proteins, and those proteins mostly control whether the cell they live in should grow or not. If it’s not time yet, don’t grow. If the cell is damaged, don’t grow. If it’s badly damaged, try and fix it. And if it can’t be fixed, smash it to bits and storm off in a huff of cytoplasm.

(So basically, tumor suppressors are like eight year old children building a Lego set. “Evil fighters”, my ass.)

The “smash it to bits” part is kind of important. If certain tumor suppressors are working properly — but the rest of the cell isn’t, the bum — they can trigger a process called programmed cell death, also known as apoptosis. This is pretty much what it sounds like — slapping a proverbial “KILL ME!” sign on the wall of the cell, and letting the body rip it limb from limb.

Gruesome, maybe — but better than having a mutated cell grow out of control, and eventually form a tumor. Any good horror movie will tell you: better to off yourself in an emergency than to join the mutant zombie horde. All that shambling around is exhausting, and who wants brain stuck between their teeth?

Anyway, tumor suppressors are very important genes; they’re just not named especially well. Fighting evil — or tumors — gets so much attention that the real everyday jobs these genes naturally do barely gets recognized. Instead, they’re known for a function they serve almost by default.

It’s like labeling a butt plug a “poop suppressor”; technically true, but not really what the thing is actually used for. Which, as any Parisian can tell you, is a giant Christmas tree.

I bet that thing would suppress the shit out of some tumors. Ho ho ho.

Image sources: CISN (crash into cancer!), Government Executive (Burns, tenting), Sparkles and Crumbs (sweet-tooth Superman), HugeLOL (apoptosis, post mortem), BoingBoing (Parisian Christmas tree art, aka “O Pluggenbaum”)

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