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# Care to speculate? Where does the other gram come from?

Fri 13 May, 2011 02:05 pm
Mo's been working on a science project regarding snake digestion.

Here's how he's doing it: weigh the snake, weight the mouse, let the snake eat the mouse, weigh the snake.

His hypothesis was that snake weight + mouse weight = after eating snake weight.

But this isn't true.

It turns out, for example, that snake weight (140 grams) + mouse weight (2 grams) = not 142 grams but 143 (average) grams. Consistently.

Mo's already disproved his hypothesis so he doesn't care where the extra gram comes from but it's driving me CRAZY.

At first I thought that maybe it was air in the snakes lung (which raises the question of whether air in your lungs changes your weight). That it had to hold it's breath while it ate because it's mouth was so full but it turns out that snakes have this mouth appendage thing that comes out to let them breathe while they eat.

What in the world could account for this extra gram?

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Type: Question • Score: 5 • Views: 1,680 • Replies: 16

3
Fri 13 May, 2011 02:13 pm
@boomerang,
how much air is in a pound?

unless you can compress it quite a bit...

no clue as to the extra snake gram.
sozobe

4
Fri 13 May, 2011 02:16 pm
@boomerang,
Maybe eating makes the snake thirsty/ water helps with digestion? So it has 1 gram of water at some point after/ while eating the mouse?
0 Replies

chai2

1
Fri 13 May, 2011 02:19 pm
I think the mouse got scared and pooped out a gram of poop inside the snake.

Problem solved.
0 Replies

JPB

4
Fri 13 May, 2011 02:54 pm
@boomerang,
How many times did you weigh the snake and the mouse separately before you weighed them together? If the total weight averages 143 grams that tells me that you're getting some fluctuations in your weights. Maybe the snake weighs 140.3 grams and the mouse weighs 2.4 grams and the total is 142.7 grams. Depending on the accuracy of your scale the 140.3 and 2.4 might have rounded down to 140 and 2, but in combination rounds up to 143.
boomerang

1
Fri 13 May, 2011 02:56 pm
The snake is weighed right after eating. He goes from the eating tank to the scale then back to his regular tank where the water is. So it isn't water.

If the mouse had a gram of poop it would be weighed in the first weighing. We buy pre-killed mice anyway to that won't work.
boomerang

1
Fri 13 May, 2011 02:59 pm
@JPB,
Quote:
How many times did you weigh the snake and the mouse separately before you weighed them together? If the total weight averages 143 grams that tells me that you're getting some fluctuations in your weights. Maybe the snake weighs 140.3 grams and the mouse weighs 2.4 grams and the total is 142.7 grams. Depending on the accuracy of your scale the 140.3 and 2.4 might have rounded down to 140 and 2, but in combination rounds up to 143.

I think that has to be it! Thank you!!!

Our scale is, I think, pretty accurate but not to 1/10 of a gram.

(But ooops on Mo disproving his hypothesis.)
0 Replies

chai2

1
Fri 13 May, 2011 06:32 pm
@boomerang,
That was a joke about the poop.

I was thinking it is what JPB suggests

2 rounded down numbers of grams that round up when you put them together.
boomerang

1
Fri 13 May, 2011 07:08 pm
@chai2,
I assumed that you were but didn't know for sure so I didn't want to be all "HA HA" so I took the other way out.

I thought it was funny and gave you an upvote. One of the reasons we don't do the whole live mice thing is because I couldn't stand to see a mouse that scared.
0 Replies

maxdancona

1
Fri 13 May, 2011 07:38 pm
Air in your lungs would effect your weight, except it would be a small amount (my quick calculation says that 1 liter of air would weigh about a gram and it is doubtful that a snake's lungs holds anywhere near that amount). Also there is no reason to expect that their would be more air in the lungs after eating.

Oxygen in your blood, from their air, would affect your weight. It might be that the mouse gets more oxygen in its blood after eating.

I also wonder if you calculated the margin of error. One gram could be well within the margin of error meaning that the two values are effectively the same.
0 Replies

rosborne979

1
Fri 13 May, 2011 07:41 pm
@boomerang,
It has to be measurement error of some form.
0 Replies

boomerang

1
Fri 13 May, 2011 09:51 pm
I think JPB nailed it -- our scale wasn't accurate enough to weigh baby snakes and tiny mice with complete accuracy.

I know most animals don't hold their breath when they eat but most animals don't eat something 20x the size of their mouths in one bite either! I figured they must hold their breath but then I found out about the.... breathing appendage (?) that snakes have.
0 Replies

Setanta

3
Sat 14 May, 2011 02:31 am
It's the ghost of the mouse . . . if you waited long enough for the mouse ghost to escape the snake, everything would be back to normal . . .
boomerang

1
Sat 14 May, 2011 07:18 am
@Setanta,
Oh! So freeing a ghost is an act of digestion!?

Is that, you know, for, like, all ghosts or just mice ghosts? Because.... um.... that would make me really afraid of ghosts.

I'm going to comfort myself by believing the a mouse ghost is somehow trapped by the freezing and that .... like.... human ghosts are not just some digested..... remnant?.... because that would be wrong.

But it might explain why ghosts are so pissed off.... right?
tsarstepan

1
Sat 14 May, 2011 07:24 am
@boomerang,
Care to speculate why Stop and Shop is sponsoring this thread as I type it?
boomerang

1
Sat 14 May, 2011 08:32 am
@tsarstepan,
Is it run by ghosts?
0 Replies

Setanta

1
Sun 15 May, 2011 04:14 am
@boomerang,
That and the fact that most people ignore ghosts, especially mouse ghosts.
0 Replies

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