Kidney Physiology

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Great overview

Urine Production Video - Osmotic Gradients

This is kind of fast, but it shows the counter-current diffusion of water and ions from the Nephron loop and vasa recta.

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Respiration, Oxygen, and Hemoglobin

By decreasing pressure inside the thoracic cavity, we are able to inspire air.  By contracting the diaphragm, intercostal muscles, and others, we increase the size of the thoracic cavity, which in turn lowers the pressure to the point that it is lower than the outside air, causing a pressure gradient so the air rushes into the lungs.  To exhale, it is the opposite- relax the muscles, decrease the space in the cavity, which increases the pressure inside until higher than outside, so the air rushes out to where the pressure is lower.

This video is a good summary.  The embedding doesn't work, so you'll have to click the link instead.  Just left the embed on there for the picture. :)

http://youtu.be/V1FAnE31AYs

Partial Pressure
Total Pressure of air can be broken into the partial pressures of all the gases contained in that air.  For instance, if the atmospheric pressure is at 760 mm Hg, and 20% of that is Oxygen gas, 80% Nitrogen gas, then the partial pressure of O₂ would be 20% of 760 = 152 mm Hg.  Partial Pressure of N₂would be 80% of 760 = 608 mm Hg.

This illustrates how increasing the pressure, as in the B picture, causes more gas to diffuse into the liquid.  A simple way to think about it is just that the higher the partial pressure of that gas, the less space it has to bounce around in the air, so more of it will end up in the liquid.

Here's a long video on partial pressure and gases getting into solution, I didn't watch the entire thing yet but it looks like a good detailed explanation for those who feel they could use more information.

Deer Carcass - Determining the Cause of Death

I was wandering around the Dry Canyon area with my boyfriend and we ran across some awesome stuff.  First off, we found a partial skull, which I of course kept, and not far off, we found a mule deer carcass!  There was fur everywhere and even looked as though the animal had been dragged to a more protected area in the bushes, as you can see in this picture:

Here I am next to the carcass, holding the skull

However, it didn't appear that any of the bushes were broken from the animal being dragged in there, and the way the animal was prostrated (particularly the position of the front limbs) didn't seem to indicate dragging but almost rather that it had laid down there.

See my geeking-out face?  Also notice the front limbs curled neatly under the animal.

So, obviously I'm no expert in forensics or animal behavior, but it was fun to try to guess how the animal died and how its body came to be where and in what condition it is.  Did it die of natural causes, and was later ravaged by scavengers who tossed hair to and fro so the surrounding area is littered with it?  Did a predator kill it and drag it out of the way?  Could it even have been a cougar cache at one point?  Let's look at each possibility.

Cougar Cache
There is evidence that could be consistent with dragging a killed animal to a safer place.  However, there is no evidence that any attempt was made to bury or cover it as cougars usually do with their caches, as in these pictures:

There also doesn't seem to be a lot of blood soaked into the fur of the animal as would be expected if it had been killed by a predator.  I would think the neck would be covered with blood if a cougar had brought it down.

Head, neck and open thorax of deer.  Notice lack of blood on fur.

Based on the evidence and that information, my conclusion is it's definitely not a cougar cache.

Another Predator
Perhaps a coyote or even dog brought down the deer?

Died naturally & later scavenged

Regulation of Blood Pressure

Blood Pressure is a very important aspect of homeostasis.  So naturally the body has many methods of monitoring and adjusting blood pressure to keep within a range that is functional for life.


Baroreceptor Reflex
Baroreceptors are located in the aortic arch and carotid sinuses (pictured below).  These are mechanoreceptors that respond to stretching of the arteries in response to blood pressure.

When these receptors are stimulated, nervous impulses are sent to the medulla oblongata of the brain where the reflex centers for vasomotor, cardiac, and respiratory are.

My Village

Aside from being completely off-topic for this blog (which I do only VERY rarely..like maybe twice in 125 posts), this long and sappy, but heartfelt and true post is for those who make a difference in my life.

I am grateful today for the people and places who help me get through this crazy time of life.  Being a single mom is no fun, especially when it comes to stress and finances.  There are great programs in the community that have helped me pay for school so I wouldn't end up stuck in a dead-end job, watch my kids when I need to go to the doctor or just need a few hours off, help pay utility bills, knock $10 off my monthly phone bill, get me $10 per month internet, pay for my food so I have one less thing to worry about in taking care of my family, pay for child care so I actually CAN go to school and work.  I complain a lot about the bureaucracy of the Department of Workforce Services, but in all truth I'd never have made it this long without them.  Thank you.  The Family Support and Treatment Center is my rock...I literally thank God for the nursery there, counseling services, etc.  They've done so much for me.

Individual people have found and given me jobs, loaned me gas money even though they were pretty much broke themselves, informed me about more community resources, picked up my children and watched them for me when I couldn't get there in time myself, or graciously let me bring children to meetings where that would normally not be okay because I couldn't get anyone to take them, given up pretty much every single weekend to babysit my kids even when I have to postpone paying them or "pay" them with food.  Many have listened to me whine and encouraged me to keep going for my goals.  Some close friends were there for me when I didn't know who else I could possibly call, and they gave me love, understanding, and excellent advice.

Wonderful brothers who take my kids under their wings, a sister who let me crash her house for over a year which also made my summer in Oregon a possibility, the best father ever who single-handedly got me through Anatomy by watching my kids 2 or 3 times a week and gave love and support and still does.  A friend who took my kids overnight when I was very ill so I could just...sleep.  A man who fell in love with my kids over the summer and goes out of his way to show he cares about them.
Thanks to all the people who continually encourage me in the things I do.

Friends who tell me I'm awesome, that I can do it, that I will reach my goals and don't give up on those dreams, love me unconditionally, give me great advice, act as a listening ear and a shoulder to cry on, and tell me like it is, cutting through all the bullsh**.  You are the best kinds of friends, love you guys.

One unknown, wonderful person left a gift at work for me which made all the difference now as I am experiencing an interruption of food stamps, but I got to use that gift card a few days ago and have enough to feed my family.  Thank you, whoever you are.

It really takes a village to do this single mom thing.  I get discouraged and overwhelmed frequently.  But it's so good to remember what all these beautiful people have done for me.  For the part each of you have done, large or small, I thank you from the bottom of my heart, and I love you all.

Vision - colors

This podcast about color is so awesome.

Wish I could have the eyes of a mantis shrimp!  We have only 3 types of cones (photoreceptors) for color vision, they have SIXTEEN!  I always feel like there must be colors that I can't see and wonder what they would look like.  I will be coloring a picture and looking around for different colors to use and I just can't find them and I realize that's all that I can see.

Brains!

Brain Day at The Leonardo was a blast.  I now have a picture of me holding a real human brain- woohoo!

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Heart

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Here is a pretty good visual to show what gap junctions and desmosomes are.  The heart has both.

Spelunking aka Caving near Rock Canyon

There are a few small caves around the Rock Canyon area.  One is right next to the trail on the north side of the canyon.  But on Thursday, a friend of mine took me to see a much less-well-known gem.


Here you can see our meanderings...we took the, umm... "scenic route" to finding the cave.  By that I mean, we went straight up the mountain and across a couple ravines before we finally gave up and headed back down, at which point we found the cave maybe 30 meters from where we started.

Fall colors in March?

Lichens!

As we are coming down...oh THERE it is!

The entrance

Tight squeeze

I'm actually proud of myself.  I am a bit claustrophobic and I was worried that I would get in there or half-way in and have a freak-out.  Almost backed out but pep-talked myself, "you can do hard things...it will be worth it."  I took a deep breath and closed my eyes and quickly shimmied myself inside.  The payoff was immediate and well worth pushing through my fear.  These pictures don't come close to doing it justice because they were taken using an iPod and a flashlight. lol

Opens up big enough to stand

Tiny stalactites

Dripping stalactite

Glassy yellow deposits on the wall - minerals? Bacteria excrement?

Green deposits on wall

Coming out took a lot more wiggling, but was less scary than going in. :P

 This cave looked natural except the back ended so abruptly I wonder if it had been dug out at least partly.  Really not sure.  But it was very cool.

Einstein and Pie - I mean Pi

Today is a very special day for two reasons - Albert Einstein, and Pi!
Albert Einstein was born on March 14, 1879.

And today's date is the first three digits of Pi -  3.14 which are pretty much the only digits the typical person knows.  Pi is an irrational number, so the digits are infinite and non-repeating.

The best Pi ever... today I'm going to listen to this song, eat a piece of pie, and solve the area of a circle all at the same time. ;)

My favorite Einstein quotes:
"The problems that exist in the world today cannot be solved by the level of thinking that created them."

"Whoever undertakes to set himself up as judge in the field of truth and  knowledge is shipwrecked by the laughter of the Gods."

"The only source of knowledge is experience."

"It's not that I'm so smart, it's just that I stay with problems longer."

"If we knew what it was we were doing, it would not be called research, would it?"

Lastly, my personal and blog motto:

Videos for Einstein's Theory of Relativity

Happy Pi Day - go eat some pie!