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pgr

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  1. Thank you so much for your comments! :) I'm always struggling to figure out how to balance constructive critiquing with encouragement.
  2. This is DD11 final project for WWS1, written completely independently from choosing the topic to completion of final product. I've given her some feedback, but I would love outside opinion for my own reference, please! She's my eldest, and I'm often unsure of where she stands... She does have all the direct quotes footnoted, but they're not copying here for me. Thank you!! BLOOD AND CIRCULATION Circulation is one of the most important processes in the human body. If it stops, you’re dead. It is as complex as anything, but also very simple. It all begins in the chest. When you breathe in, you breathe in oxygen, which your body needs in order to survive. But how does that oxygen get around your body? Well, that’s where circulation comes in. Once it is gets into the lungs via the nose or mouth, the oxygen hitches a ride on some red blood cells and zips along the pulmonary vein to the heart.(Note: the pulmonary vein is the only vein that carries oxygen. All of the others carry carbon dioxide. Similarly, the pulmonary artery is the only artery that carries carbon dioxide, and all of the others carry oxygen. Scientists call them that because arteries carry blood from the heart and veins carry blood to the heart.) “Inside, it [the heart] has four…chambers…each top chamber is called an atrium…each bottom chamber is called a ventricle.†At the beginning of its journey, the oxygenated blood (blood with oxygen) is pushed into the left atrium.“In each opening [between atrium and ventricle] …a valve…makes sure the blood flows in one direction.†Therefore, the blood now comes into the left ventricle, then shoots into the aorta, the body’s largest artery, and out of the heart. Then the blood traveles through the arteries and drops the oxygen off at different parts of the body. Now, because there is a set amount of blood in the body, that blood-also carrying lots of carbon dioxide (a poisonous gas)-needs to get back to the heart and the lungs. But how? At this point, the arteries start to get narrower. Soon, they get so narrow that they are not arteries anymore, but ridiculously tiny blood vessels called capillaries. Then the blood comes into these capillaries and travels along them until the blood vessel starts to get larger and becomes a teeny-tiny vein, but a vein nonetheless. Then it slips through the vein-which keeps getting bigger and bigger-until it gets back to the heart. At its destination, the deoxygenated blood comes into the right atrium through the vena cava veins first. Finally, it swoops into the right ventricle and back to the lungs through the pulmonary arteries, and you breathe out. This whole process takes place in less than a couple of seconds, maybe even less than one. And from the moment that you are born, to the moment you die, it never stops. Blood is very important in circulation. “Whole blood…delivers oxygen…; it removes carbon dioxide and cell waste…; it transports nutrients…; it carries hormones, medication, and enzymes…; it clots to preserve…blood…; it delivers antibodies and fights infections; and it helps regulate body temperature.†Some people feel faint at the sight or even the mention of blood, but there’s really nothing to get woozy about. Blood is truly fascinating. “There is an average of 4-5 liters of blood in an adult.†Since there is so little of this red liquid, the body works very hard to keep it inside. It does so with little cells called platelets. When you get a paper cut, or your sweet little puppy decides to nip you and punctures your skin, or the school bully trips you and you land on the sidewalk and scrape your knees and elbows, you start to bleed. Your body knows it has to save the rest of your blood from leaking out, it really does. But how does it do that? Once you start to bleed, the punctured blood vessel automatically narrows. Almost immediately, platelets swim over to the hole and stick there. “A special protein†called prothrombin also helps clog the wound, and soon you get a scab, which will eventually fall off by itself. Don’t try to peel it off! Platelets, like all other blood cells, “live†in one of the three layers of blood. Those three layers are plasma, red blood cells, and the buffy coat. Red blood cells (duh) contain red blood cells, the buffy coat contains platelets and white blood cells, and plasma contains everything else, like sugars, salts, and proteins. Now you know what platelets are, but what are those white and red blood cells? Red blood cells carry oxygen and carbon dioxide. They also carry a protein called hemoglobin, which they can’t carry the gases without. They are red, of course, and shaped like doughnuts, just without the holes. They are also flexible. There are billions-maybe trillions-of red blood cells in the body. In fact, “in one drop of blood, there are approximately…300 million RBCs [red blood cells].†That’s a lot! And all of them are basically the same, because there is only one type of red blood cell. White blood cells (WBCs) are a little more diverse, but there are much, much fewer of them. “For every 600 RBCs, there is one WBC.†There are tons of different types of WBCs, but they all do the same job. That is job is to protect your body from bacteria, viruses, and infections. When an invader like a flu virus comes into your body, a WBC comes over to it and chomps it up like a potato chip! Two types of WBCs, by the way, are called lymphocytes and leukocytes. Another type is called a natural killer cell. And finally, though some people find blood frightening, maybe even have nightmares about it, it’s truly a fascinating and vital liquid that all of us have inside our bodies, and nothing to be afraid of.
  3. Could someone please point me in the direction of "Ruth's epic writing thread"? Thank you! :)
  4. I will be missing many (most?) of the conferences that I have signed up for, and will need to view the material on my own. I've searched but not found info on the archived material - how long will it be accessible? Thank you!
  5. AAAaack! I am usually mobile, and just became aware of the conference series today. And AOPS/Richard Rusczyk is sold out!! :( I wouldn't have been able to participate, as it will be taking place right at mid-bedtime here, but I so wanted to watch the recording. Anyone know if it will be available? I only wonder as it's a free seminar.
  6. I have to go back and look at the Hewitt text (which I also own...if only buying a book would somehow just allow for absorption of the information it contains.... :P ) - the topics in Trefil seemed more integrated, though I think you're right about the text. I've ordered Dr. Art's book & am looking forward to getting it. :) Thank you!
  7. That's both helpful and encouraging - thank you so much :). I've gotten very frustrated trying to piece something together, and keep second guessing myself. I appreciate the input & recommendations :).
  8. Has anyone used the book "The Sciences: An Integrated Approach" by Trefil and Hazen? http://www.amazon.com/The-Sciences-An-Integrated-Approach/dp/0470118547/ref=pd_rhf_gw_p_img_1 I've been trying to find a resource that I could use as a sort of a spine on which to base an integrated science repeating rotation. My kiddos are still young for the acutal text, but I have been considering following the topic layout. I wonder if it's a comprehensive enough sequence for elementary - high school.
  9. I know this had been discussed in the past; I just wanted to make sure I didn't miss anything in my search... Do I understand correctly that HST+ (non online version) will not work with a Mac? My PC is dying, and I use HST+ for record keeping (as opposed to planning). Love HST, but I'm fed up with the PC and am thinking of getting a Mac. It seems OLLY is the best Mac compatible program, but HST serves my purposes very well & I'd love to continue to use it.
  10. Thank you for the replies! I ended up downloading flex books for both middle and high school - I really like that they seem both rigorous and readable. At least that's my impression from a very cursory look through the material :). We generally like real books as well, though the layout of this may just work for us.
  11. I'm trying to roughly plan our science studies working backwards. Any opinions regarding CK-12 online high school textbooks? Am I correct in thinking they are college prep level? I'm weighing various texts based on both scope/sequence and content. I'm also looking at Hewitt Physics, Campbell Bio, and Chem & Earth science from Pearson pub. The obvious advantage with CK-12 is the ability to access content vs just table of contents at this fairly early stage. Thank you! :)
  12. It seems there's a fairly active homeschool community around Bangor - I don't know anything about northern areas such as Houlton. I'll share the picture we've gotten, but must preface that we're currently still in Pittsburgh, so this may or may not be accurate... Overall, the general impression we've gotten is in agreement with Krista. It appears that many people have a romanticized picture of Maine - "vacationland", though it seems the reality is that it can be a bit rough. High poverty and prescription drug abuse, scarce jobs, high taxes. Though real estate is relatively less expensive. On the positive, seems the nature is just gorgeous, and the people are both laid back and tolerant. If you've got a job and like winter, it seems life can be good in Maine :). My husband's current position has now been terminated, and the position in Bangor was the only one that is remotely like what we're looking for, so we'll be moving to Bangor in early 2014.
  13. I still haven't found the link - not sure if it's still active?
  14. Has this expired? I tried to order the PC Download, but it is telling me the code is not valid. :(
  15. I have been wondering this, as I've been researching for upcoming years - thank you for posting this poll. I wonder if someone with the K12 link would please be willing to PM me as well? No luck with Google :(.
  16. That makes sense. I just don't want to be "truant" for a few months, but yes-it's not likely someone is going to come to the door to check on us.
  17. You are all putting me at ease - thank you! I'm likely being ridiculous, but just to clarify - if we're moving from PA, would I notify when actually moving that we're leaving the state (because if they decide that they would, in fact, like a portfolio submitted and an evaluator to assess - we would need to still be in PA), and then "disappear" for a few months before submitting to Maine as soon as we're there?
  18. Why on earth didn't I think of that?? :D & thank you - we were planning on leaving PA, but this really sped things up, and we're thankful to have a likely new job lined up - and the decision already made for us that it's the one he's going for :)
  19. We're currently in PA. This is the first year we've had to submit paperwork, as DD just turned 8 this summer. I've submitted all the required documentation. DS5 is in Montessori K. DH's position has been terminated, and we will likely be moving to Maine. OK, so I planned to submit a letter notifying PA of the move, and then going by Maine requirements after we have moved. Straightforward, right? Only now it looks like we'll need to stay with family in WV for 1-2 months after we leave PA, and before moving to Maine. If we weren't selling the house, I'd continue as if living in PA. If I had an address in Maine, I'd just start reporting to Maine. But the only address we'll have is that of family in WV. There I would need to submit paperwork for both DD8 and DS5- including instruction plans, etc. And then close out by notifying that we're moving again a few weeks/months later?? What do you do when living somewhere that temporarily?
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