bones cracking from screws

I found that bone cracking can happen between screw holes but it is not very common. So I guess it is just like someone who works with wood once they get good enough it shouldn't crack because they know what they are doing. I also found that the screw type can effect it. I found this at ota.org

Cool Memory Game

The Stratum Corneum

The Stratum Corneum (SC) is the top layer of the epidermis, it has an average thickness of .01 - .02mm. (10 - 20um)

Following a 14-day cycle, cells from
lower epidermal layers flatten, rise and fill with the
protein keratin to form SC. While a cross-section of
the SC reveals inter-digitated cell layers surrounded
by a lipid lamellar matrix, similar to bricks and mortar,
a top-view reveals complete surface coverage
resembling a soccer ball. Keratin, the main component
of SC, is the same metabolically inactive protein in
hair and fingernails, making it easy to study in vitro.

Src: Mechanical Properties of Human Stratum Corneum:
Influence of pH-Treatment
Rena Rudavsky, Mechanical Engineering, Columbia University


View Article

tanning

Question- What causes people to tan better?

Melanin is the body's way of protecting skin from burning. Darker-skinned people tan more deeply than lighter-skinned people because their melanocytes produce more melanin. But just because a person doesn't burn does not mean that he or she is also protected against skin cancer and other problems.

Information from teens health at

http://kidshealth.org/teen/safety/safebasics/tanning.html

Question 5

The human body is 61.8 percent water by weight.

Science Fact Finder

October

Hey!

Here's this new blog thing. Let's try it...maybe we'll like it. Here's how it works.

Answer the question in a New Post. Don't make a comment to this page. You must provide the source of your answer. Wikipedia, Ask.com, Yahoo answers (and there will probably be another few added to this list) DON'T COUNT!

First person to answer correctly gets 5 points (maybe 10). You can only answer 1 question per week.

Questions for the week..

1. How thick is the Stratum Cornneum?
2. Why doesn't bone crack when you put a screw in it?
3. What causes people to tan better?
4. Why do scars hurt?
5. What percent of our weight is water?

Good luck!