Wednesday, March 31, 2010
What is the Gestation period of an Octopus, and How Many Babies Does it Produce? GUEST BLOG
We've had a lot of interest in octopi...
Todays guest blogger is Alex
An octopus has a fairly long gestation period, lasting around 11 months, and that’s without considering the chance of delayed implantation, which can last up to 3 months. But seeing how long it takes for the female to produce eggs, it’s no surprise that that amount of eggs produce would be a large number.
The female produces a good 200,000 eggs on average. These eggs are guarded for about 50 days before they hatch. The mothers do nothing for these 50 days but defend the eggs, not even eat or sleep. After the eggs have hatched, most females die from starvation and fatigue, while the male dies a few months later. Seeing how there is no one to defend them, only about 1% of the hatched eggs will survive being hunted down by predators.
Source: http://jrscience.wcp.muohio.edu/fieldcourses03/PapersMarineEcologyArticles/Octopus.html
Tuesday, March 30, 2010
What is Trichinosis and How Big a Problem Is It? GUEST BLOG
Todays guest blogger is Miranda
Trichinosis is an infection caused by the consumption if improperly cooked meats such as pork and bear. Most of the contaminated meat is wild game that has been improperly cooked.
The larvae of Trichinella spiralis are in meat, and it migrates through the human body in order to embed itself in muscle tissue or intestinal walls. These larvae mature and reproduce. The new larvae attack new host organs while the old are excreted. The incident rate has decreased in the US and it is very uncommon. There are about 30 cases a year and they mainly pertain to wild game consumption. It is a common disease across the globe. It can be treated with antibiotics, but many times symptoms go on without being noticed. The larvae can live dormant for years and symptoms can range from unnoticeable to fatal. The best way to prevent the infection is by freezing the meat or cooking it to a high temperature.
Source: http://www.cahfs.umn.edu/prod/groups/cvm/@pub/@cvm/@migrate/documents/asset/cvm_48856.pdf
Monday, March 29, 2010
How Old Do Octopi Get and How Strong Are They? GUEST BLOG
Today's guest blogger is Rachel.
The life span of octopi varies from different species. The larger octopi usually live longer than the smaller ones for example, the giant octopus, O. dofleini is thought to live for 3-5 years. Whereas some of the smaller spices tend to live for only a year or two. Besides the species the water temperature also seems to have an effect on the life span. The giant octopus, O. dofleini lives the longest at temps of 10 C or so.
Octopuses are known also to be very strong for their size. An example of their incredible strength is some octopuses kept as pets have been known to open the covers of their aquariums and survive for a time in the air in order to get to a nearby feeder tank and gorge themselves on the fish there. They have also been known to catch and kill some species of sharks. Although they are incredibly strong their strength is mostly used for movement rather than as a predator, they use their strength to propel and escape from their predators and also to open shells and move obstacles. The more dangerous aspect of octopuses is their poisons from their bite.
Source:http://www.cephbase.utmb.edu and http://marine.alaskapacific.edu/
Saturday, March 27, 2010
Do Clams Have as Sophiticated Nervous Systems as Ocotopi? GUEST BLOG
Today's Blog is written by Brooke.
The nervous system of mollusks varies from the clams and tusk shells to the squid and octopi. The less complex organisms such as the clam have a simpler nervous system compared to the octopi which are more complex. A typical nervous system of a mollusk includes a pair of cerebral ganglia which is a mass of nerve cells. They are located in the head, mouth, and similar sense organs. The dorsal cerebral ganglia contain two pairs of longitudinal nerve cords in the mantle, also called pleural ganglia. The ventral pair of nerve cords are found in the foot and form pedal ganglia.
Source:http://geology.er.usgs.gov/paleo/mollusks.shtml
Friday, March 26, 2010
Can Worms Regenerate Themselves? GUEST BLOG
Today's Blog is written by Caitlyn.
Annelids are one of the most complex organisms. Take the palolo-worm for example. They are fully capable of regeneration when they are cut in half. This allows them to reproduce asexually by releasing an end of their tail. This then creates a complete organism. But only the tail can be cut off and regenerated because the worm must have the piece contains the clitellum and at least 10 segments behind the clitellum.
Source:http://invertebrates.si.edu/worms.htm
Thursday, March 25, 2010
How Long Does It Take To DIgest Gum? GUEST BLOG
Today's Blogger is Mandi.
The human body is excellent at breaking down nutrients from things we eat and using them for energy. While not everything we eat is digestible, it does not sit in our stomachs for seven years as the common myth states. Our stomach empties the unusable material into our lower intestine where it is passes to stool often enough to keep the stomach open and keep us hungry.
Source: http://shc.osu.edu/blog/does-gum-really-stay-in-your-stomach-for-7-years
Wednesday, March 24, 2010
Is It Bad To Write On Your Hand?
Writing notes on hands, arms, and even legs appears to be very common in high school and even beyond (re: Sarah Palin).
I could find no scientific research that indicates the skin is permeable to the ink found in regular pens. There have been several studies on the safety of India Ink which is used to mark mucosa in pre-surgery patients (deemed to be safe) and additional studies on ink used in tattoos. Tattoo ink is not regulated by the Food and Drug Administration (FDA) and may contain metal salts.
Source:http://chemistry.about.com/library/weekly/aa121602a.htm
Monday, March 22, 2010
Why do some athletes not have hair on their legs?
Many athletes remove hair from their legs, arms, back and chest because they believe it improves their speed and agility. Swimmers are the best example of this. Other athletes remove hair because smooth arms and legs make muscles look bigger and more toned. Hair removal can be done by shaving, waxing, or laser treatment.
One article published in 1992 by Johns, Houmard, Kobe, Hortobagyi, Bruno, Wells, and Shinebarger did find that "shaving significantly increased distance per stroke (P < 0.05) by [almost equal to]5%. These data indicate that reduced training specifically improves swim power; however, removing exposed body hair after taper may additionally enhance performance capabilities by increasing distance per stroke"
Source: Medicine & Science in Sports & Exercise Volume 24(10).
Sunday, March 21, 2010
Why Are Calories Posted on Foods in California But Not Here?
You are very observant! I noticed the same thing while I was away on Spring Break.
Some states have made a law that requires restaurants to post the number of calories in food items. Massachusetts, California, Maine, New Jersey, and Delaware have all -passed laws requiring the calorie posting. The idea is to give consumers more information about the food choices so they can make a decision based on taste as well as nutrition.
Some research has been done on the effectiveness of this added information - does it change people's food choices? "The Stanford study, released in January (2010), looked at customers at New York City Starbucks locations and found that customers ordered an average of 6% fewer calories (232 versus 247) after labeling rules were implemented. Most of the calorie reductions came from consumers’ food (rather than beverage) choices; Starbucks’ revenues were unchanged."
Source:http://www.rimag.com/article/452343-Menu_Labeling_Full_Disclosure.php
Saturday, March 20, 2010
What kind of fish is "green" fish?
This question comes from a student who saw a note on the bottom of a menu that stated the restaurant only served "green" fish and wanted to know what type of fish were green.
I don't think this restaurant was talking about the color of the fish but instead was referring to the sustainability of the fish in the ecosystem. Americans are becoming increasingly familiar with the need to be more sensitive to the overfishing and the dying out of certain fish.
"Green" fish may be fish that are not commonly on the menu. They may consist of by-catch (fish that accidentally gets caught in nets when fisherman are really after something else) or farm raised fish.
The Monterey Bay Aquarium has a great site devoted just to this topic:
http://www.montereybayaquarium.org/cr/seafoodwatch.aspx
Friday, March 19, 2010
Since cheese is a mold, is mold on cheese bad to eat? GUEST BLOG
Today's blog is written by Miranda.
Depending on the type of cheese, the mold on cheese could be more or less dangerous. Hard cheese is dense and the mold most likely cannot penetrate into the cheese. The mold can easily be cut off. Cheese made with mold could be more hazardous to eat if it gets moldy. Mold that the cheese was not made with has a higher probability of being dangerous. Soft cheeses can easily have mold and bacteria growing together due to the moister content. The soft cheeses should be thrown out.
Source:http://www.ucop.edu/riskmgt/bsas/bsas_op/documents/molds_food_dangerous.pdf
Thursday, March 18, 2010
Is It True That Fiber Has Negative Calories?
This question is very similar to the question about celery taking more energy to chew than it provides in kilocalories.
There are two different types of fiber; the soluble type like the fiber found in oatmeal and insoluble type as is found in celery. Both are technically carbohydrates which mean they should have 4 kcal/gram. But, since the body is unable to fully digest fiber, researchers have suggested that a value of 2 kcal/gram be used to calculate their caloric value. This recommendation is based on what is called a "mixed" diet which means that along with the fiber you are also eating other carbohydrates, fats, and proteins.
FYI: The nutrition information on celery indicates that 1 cup contains almost 4 grams of fiber and has 19 calories. This discrepancy indicates a gap in research and practice because according to Guenther and Jensen, this cup of celery should contain only 8 calories.
Source: Guenther, P.M. & Jensen, H.H. (2000).Estimating energy contributed by fiber using a general factor of 2 vs 4 kcal/g. Journal of the American Dietetic Association. 100(8).
Tuesday, March 16, 2010
Can You Find The Recipe For Dr. Pepper?
The recipe for Dr. Pepper is a well guarded secret. Last year it was reported that a man from Tulsa found the recipe for the original Dr. Pepper in a book purchased in an antique store. It turns out this was not true. See http://today.msnbc.msn.com/id/30562206/ for the full story.
Dr. Pepper lists it's ingredients on the can but does not have to give the exact amounts. It also lists "coloring" and "natural and artificial flavors" but the company does not have to specify exactly what these colors or flavors are.
One more recent update on the Dr. Pepper formulation; In November 2009, Dr. Pepper introduced Dr. Pepper Heritage. This drink has sugar instead of the high fructose corn syrup making it closer to the "Dublin Dr. Pepper".
Monday, March 15, 2010
Do You Really Need Milk To Be Healthy?
You have probably heard a million times that drinking milk makes strong bones. Some students have also asked if milk will make you taller. The facts are:
1. The body has a need for calcium in order to build strong bones and teeth.
2. Milk is a good source of calcium.
3. Other factors such as genetics, Vitamin D, and exercise also play a role in
building strong bones.
4. Milk is not the only source of calcium. Other foods such as dark leafy greens,
yogurt, cheese, and even baked beans contain calcium.
5. Many foods and supplements have been fortified with calcium so it is possible to
get an adequate amount of this mineral without drinking milk.
The bottom line: Milk may be negotiable but adequate calcium is not.
Interesting research on calcium supplementation in young girls:http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6T1B-4475VC1-F&_user=10&_coverDate=10%2F13%2F2001&_rdoc=1&_fmt=high&_orig=search&_sort=d&_docanchor=&view=c&_searchStrId=1249995126&_rerunOrigin=scholar.google&_acct=C000050221&_version=1&_urlVersion=0&_userid=10&md5=9c185c333988427d745e150c1c29daf7
Sunday, March 14, 2010
Is Cancer Contagious? GUEST BLOG
Today's blog is written by Alex.
Cancer is one of the deadliest diseases in the world, but you don't get cancer the same way that you get a disease like Chicken Pox. Inside your body, new cells are being created and destroyed constantly in order to maintain a balance. In cancer, this balance is thrown off because cells are being made in large quantities and never being killed. The cells that don't die constantly reproduce and create a large mass of cells called a tumor. The only reason this occurs is that the gene that controls the rate of the creation and deceasing of cells is damaged. This can just happen, be due to chemicals, radiation or because there was an error passed on from your parents. The damaged gene is called a mutation. Some cancers are linked with viruses, like the Human Papilloma Virus can cause cervical cancer. A type of lymphoma called Burkitt's lymphoma which is quite common in Africa is linked with the Ebstein Barr virus. You can catch the virus, but you can't catch cancer.
Cancer is hereditary. The damaged genes can be reproduced and sent down through generations to come, and though you can get cancer from various viruses, you can't catch cancer from people with cancer.
Source:www.cancer.org
Saturday, March 13, 2010
What Happens to the Loose Skin When You Lose A Lot of Weight?
The growing use and popularity of bariatric surgery has led to more and more people facing this exact dilemma. The weight is gone but the loose skin remains. After a weight loss of 50-60% of their body weight, patients are left with folds of skin on their abdomen, arms, thighs, and back. Body contouring through surgery is the only way to remove this excess tissue.
Source:Hurwitz, D.J.(2004). Single-Staged Total Body Lift After Massive Weight Loss
Annals of Plastic Surgery:52:5, 435-441.
Friday, March 12, 2010
Do I Need Regular Teeth Cleaning?
By regular teeth cleaning I assume you mean at the Dentist's office. The American Dental Association recommends "regular" visits for professional cleaning and dental check-ups. A professional cleaning can get into places that you might otherwise miss and remove plaque and tartar build up. Clean teeth are less prone to cavities because of a lower amount of bacteria.
A small but interesting Swedish study was conducted on the importance of oral hygiene in preventing dental caries. The researchers looked at a number of variables including frequency of teeth cleaning and dental visits. The results indicated that the best indicator in the preventation of tooth decay was regular brushing.
Source: http://www.ada.org/public/topics/cleaning.asp
Acta Odontologica Scandinavica 1991, Vol. 49, No. 2, Pages 97-102
Thursday, March 11, 2010
Can You Build Up a Tolerance to Poisons?
Interesting but tough question to answer.
Both plants and animals have been noted to develop a tolerance for heavy metals. Unfortunately, the extrapolation of findings between species is difficult. That means just because hamster cells develop a tolerance for arsenic doesn't mean that humans will do the same (Rossman et al. 1997).
The best general answer for to question is that any tolerance is dependent on the dose or exposure, the length of time of the exposure, individual genetic composition and the type of toxin.
Source: Christenson, J.M. Human exposure to toxic metals: factors influencing interpretation of biomonitoring results Science of The Total EnvironmentVolume 166, Issues 1-3, 21 April 1995, Pages 89-135
Wednesday, March 10, 2010
Does Chocolate Have Health Benefits? GUEST BLOG
Today's blog is written by Rachel
Moderate amounts of dark chocolate may have some heart benefits, but many claims are unproven and much more research is needed before chocolate can take its place among true healthy foods, such as fruits and vegetables, which also contain vitamins, minerals, and fiber not found in chocolate. That said, replacing the regular sweet treat in your diet with the darkest chocolate you can find (look for a high cocoa content) won’t hurt you and may have some health benefits. Also there is anti oxidants in chocolate that can help prevent cancer, but can also be found in much lower calorie foods and drinks. The calorie count on chocolate is high and may cancel all other benefits you would gain from its consumption.
Source: http://www.health.uab.edu/17646/
Tuesday, March 9, 2010
Why Can't I Control My Cough?
The Journal of Respiratory Physiology and Neurobiology devoted an entire journal to the topic of cough regulation in 2006 (volume 151, issue 3). Some of the research findings indicated that a cough can be "voluntarily induced and inhibited" which means you can control your cough.
Cough medicines work on the cerebral cortex and may inhibit the urge to cough. Another article in this issue of the Journal found that many cough syrups are only placebos and contain no ingredient that would really stop a cough at the brain stem level. The sweet taste of the cough syrup stimulates taste buds in the tongue that may influence cough "via inhibition of the cardiorespiratory area of the brain." (Eccles, 2006). That means that the sweetener in the cough medications may have more to do in helping you suppress your cough than any other medicinal ingredient in the cough preparation.
Source: Respiratory Physiology and Neurobiology, Volume 152, Issue 3, Pages 221-372 (28 July 2006) Cough and its Regulation Edited by John G. Widdicombe and Bradley J. Undem
Monday, March 8, 2010
Is Chocolate Really Bad For Dogs?
Don't be tempted to share your chocolate Easter eggs with Fido. Chocolate contains theobromine and caffeine, both of which are toxic to dogs. Dark chocolate is especially harmful to your four legged friend because of higher theobromine level (130 mg/oz compared to 58 mg/oz in milk chocolate).
It takes only a small dose to cause problems - less than one ounce of chocolate could be lethal.
Source: Gwaltney-Brant, S.(2001) Chocolate Intoxication
The brain and the heart are essential organs for life, but does one require more energy than the other? GUEST BLOG
Today's guest blog is written by Mandi
The brain cells need two times more energy than any other cell in the human body. The cells that communicate with each other, neurons, have a high demand for energy because they are always in a state of activity. Even while we are sleeping, neurons are at work fixing and rebuilding components. They manufacture enzymes and neurotransmitters that have to be sent out to the nerve branches. Bioelectric signals responsible for communication throughout the nervous system demand the most energy from neurons. This action alone accounts for half of all the brain's energy. The heart, however, only requires the same amount of energy as other muscle organs.
Source: http://www.fi.edu/learn/brain/carbs.html
Friday, March 5, 2010
What is in Hotdogs?
The content of hot dogs and frankfurters is regulated by law. So if a hot dog package says "all-beef" it can not contain soybean protein, other meats, or dry milk fillers. A regular frankfurter can contain up to 3.5 percent fillers and can contain a combination of meats.
The sizzle in a hot dog comes from the fat, in many hot dogs, 30% of the calories come from fat.
Why Do Bees Die After They Sting? GUEST BLOG
Today's blogger is Brooke.
The bee is a type of Hymenopterous insect along with wasps, yellow jackets and hornets. The female bee is the only one out of the group that looses their stinger due to stinging. The stinger is made like a barb, causing it to stay in the victim instead of staying attached to the insect’s abdomen. The honeybee will only live if the victim happens to be a human because their skin is thinner than that of animals. A mammal is the only cause to a bee’s death because the stinger gets stuck in the skin and part of the bee’s abdomen breaks off with it.
http://maarec.cas.psu.edu/bkCD/HBBiology/insect_sting.htm
Thursday, March 4, 2010
Do Cell Phones Cause Cancer?
There has been concern that cell phone use may contribute to the incidence of brain tumors. Most of the research on this topic has been done in Europe since their experience with cell phones is of longer duration than the US. Researchers to date have found no association "with glioma, meningioma, or acoustic neuroma, even among persons who had been subscribers for 10 or more years."
This is not to say that cell phones are safe as most carcinogen exposure takes decades before a tumor develops.
Source: http://www.cancer.gov/cancertopics/factsheet/Risk/cellphones
What causes hiccups, and is there a cure? GUEST BLOG
Today's Blog is written by Alex
Everyone has pondered this question before: How does one cure hiccups? Hiccups are caused by an irritation in the diaphragm, Normally, the diaphragm pulls down when you exhale and pushes up when you inhale. When you have hiccups, your diaphragm is irritated due to eating too quickly or too much, an irritation in the stomach or the throat, or feeling nervous or excited. As for a cure, there are multiple ways that people have concocted to cure this harmless affliction, but it would seem like it is different from person to person. Some people claim that you can cure it by letting sugar melt on your tounge, or by drinking from the "wrong side of the glass". These we can both consider to be untrue because neither of them resolve your irritated diaphragm. Some medicinal websites claim that doing breathing excercises can reduce the amount of hiccups had and also prevent future ones from happening.
source: http://www.scientificamerican.com/article.cfm?id=what-causes-hiccups
Wednesday, March 3, 2010
Are All Animal Eggs Edible? GUEST BLOG
Today's blog is written by Miranda.
When thinking of eggs, one usually thinks of chicken eggs. Most commonly chicken, duck, and goose eggs are eaten. Fish eggs are eaten as a delicacy. Reptile eggs are not recommended to be eaten. They are edible but they have a high risk of bacteria.
Source:http://www.ncbi.nlm.nih.gov/pubmed/19679367
Tuesday, March 2, 2010
Do Pregnant Women's Hair and Nails Grow Faster? GUEST BLOG
Today's question and answer is written by my student, Mandi.
Pregnancy changes hormones and usually causes skin and hair changes. Some women get was is called "the mask of pregnancy", which is changes in the color of the skin around the eyes and cheek. Others develop a dark line around their abdomen. Most notice a change in the texture and growth of hair and nails. Some women have stronger, faster growing nails, while others report splitting nails. In nearly all cases, nails and hair go back to the way they were prior to pregnancy. Hormones are the factor that causes these changes to skin, hair, and nails of pregnant women.
Source: http://www.umm.edu/pregnancy/000214.htm
Monday, March 1, 2010
Are Dogs Colorblind? GUEST BLOG
Today's question is answered by one of my students, Taylor.
Dogs can see color, however they cannot see every color. During the day, humans use cells in their eyes called cones to see colors. Humans have three different types of cones, which allows them to see the colors red, blue, and green. However, dogs only have two cones, which only allows them to see the colors blue and green.
Dogs are not colorblind in the sense that they only see black and white, but they do only see certain colors due to the lack of one cone in the eye.
Source: Cornell Center for Materials Research,Cornell University
Neitz, Geist and Jacobs.(1989) Visual Neuroscience
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