About.com Biology

Rosemary Reduces Carcinogens

Thu, 02 Jul 2009 20:31:56 +0000


Photo courtesy PDPhoto.org

Summer is here and you know what that means. It's grilling time. Before you put that meat on the grill, you may want to add a particular seasoning that has been found to help prevent cancer.

Researchers have discovered that Rosemary can help protect against carcinogenic compounds. They suggest adding a bit of Rosemary to meat products before grilling. In studies, Rosemary was shown to reduce carcinogenic compounds, or HCAs, anywhere from 30 to 100 percent.

For additional information, see:

To Block The Carcinogens, Add A Touch Of Rosemary When Grilling Meats (Science Daily)

Sleep and Heart Health

Wed, 01 Jul 2009 22:00:39 +0000

Researchers have shown that getting at least eight hours of sleep is needed for good heart health, especially for women. In fact, women who don't get at least eight hours of sleep are at a greater risk for developing heart disease.

The study, published in the American journal Sleep, showed that women who did not get eight hours of sleep had increased levels of Interleukin-6 (IL-6) in their blood stream. IL-6 is involved in the body's inflammatory response and increased levels are associated with coronary heart disease. For women who got five hours of sleep or less, the levels of a risk factor for future cardiovascular morbidity also increased. Men with the same sleeping habits however, did not have an increase in these same risk factors for cardiovascular disease.

Learn more about this study, see:

Lack Of Sleep Could Be More Dangerous For Women Than Men (Science Daily)

Alcohol Reaches the Brain in Six Minutes

Sat, 27 Jun 2009 06:00:50 +0000


Photo courtesy PDPhoto.org

Researchers have shown that alcohol really does go straight to the head. In fact, in only six minutes after consuming an amount of alcohol equivalent to two glasses of wine, your brain cells begin to undergo changes.

Researchers discovered that upon the consumption of alcohol, the brain processes an alcohol breakdown product for energy instead of using glucose. This can have harmful effects as it results in lowering the concentration of substances which are used to protect the brain.

So what does this mean for those who drink alcohol in moderation? According to researcher Dr. Armin Biller, "shifts in brain metabolites after moderate consumption of alcohol by healthy persons are completely reversible." He also warns however that permanent brain damage can occur as a result of consuming large quantities of alcohol, as is seen with alcoholics. Additionally, studies were also conducted on how alcohol hangover effects the brain.

Learn more about this study, see:

From The Glass To The Brain In Six Minutes (Science Daily)

Diffusion and Passive Transport

Fri, 26 Jun 2009 11:39:22 +0000

Diffusion is the tendency of molecules to spread into an available space. Without other outside forces at work, substances will diffuse from a more concentrated environment to a less concentrated environment.

Passive transport is the diffusion of substances across a membrane. This is a spontaneous process and cellular energy is not expended. Molecules will move from where the substance is more concentrated to where it is less concentrated. The rate of diffusion for different substances is affected by membrane permeability. For instance, water diffuses freely across cell membranes but other molecules can not. They must be helped across the cell membrane through a process called facilitated diffusion.

Osmosis is a special case of passive transport. In osmosis, water diffuses from a hypotonic (low solute concentration) solution to a hypertonic (high solute concentration) solution. Generally speaking, the direction of water flow is determined by the solute concentration and not by the "nature" of the solute molecules themselves.

Mediterranean Diet and Long Life

Thu, 25 Jun 2009 16:14:23 +0000


Photo courtesy PDPhoto.org

Everyone knows that a healthy diet including fruits and vegetables is good for you and may even help you live longer. Researchers have discovered that eating specific foods from what is known as a Mediterranean diet will make you healthier and increase your life span.

The basic type of Mediterranean diet that is linked to long life includes eating high quantities of complex carbohydrates, specifically fruits, vegetables and legumes. High quantities of nuts and olive oil should also be consumed along with moderate amounts of alcohol and low amounts of meat. Consuming excessive amounts of alcohol and/or meat is not linked to living longer. Other types of Mediterranean diets that were found not to be linked to longevity, include diets that are high in seafood, fish and cereal and low in dairy products.

Learn more about this study, see:

Longer Life Linked To Specific Foods In Mediterranean Diet (Science Daily)

Immune System Questions

Sat, 20 Jun 2009 06:00:26 +0000


White Blood Cell Credit: Bruce Wetzel and Harry Schaefer/National Cancer Institute

The immune system is the body's natural defense mechanism. It protects us from invaders that we can't see, like viruses and bacteria.

The immune system uses two types of defense mechanisms depending on the threat to the body. Nonspecific defense mechanisms provide the first line of defense. In cases where microorganisms get through the primary deterrents, there are back-up systems called specific defense mechanisms.

Do you know which type of immunity protects the body from its own cancerous cells? Test your knowledge of the immune system. Take the Immune System Quiz!

Learn more about the immune system:

Scitable: Online Science Library

Fri, 19 Jun 2009 13:24:42 +0000

For those who love the science journal Nature for its ability to make important research information and scientific advances understandable to the general public, I have some good news. The science publisher, Nature Publishing Group, has created an online science library known as Scitable. The information you will find there mostly focuses on genetics and is intended for students, teachers, professionals and those interested in scientific developments.

This resource provides access to the valuable research and content developed and published by Nature over the years. Teachers are able to browse content and set up course-packs of Scitable articles. They can also create public and/or private groups for their students. Students can access information and overviews of key biology concepts and even ask an expert questions related to topics in their field of research.

Bacteria Anticipate Environmental Changes

Wed, 17 Jun 2009 16:40:46 +0000


E. coli bacterium © Dennis Kunkel

Researchers have discovered that bacteria and other microorganisms have the ability to predict changes in an environment and prepare in advance for the coming changes. Much like in Pavlov's adaptive anticipation experiments with dogs in which they were trained to salivate at the ringing of a bell, bacteria also have the ability to adapt to their environment through conditioned response.

E. coli bacteria are found normally in our digestive tract. While some mutant stains can be harmful, those that are part of the normal flora of our intestines help in digestion and provide us with certain vitamins. In the study, researchers discovered that E. coli bacteria in the environment of the digestive tract have been conditioned to recognize that the sugar lactose is followed by an additional sugar called maltose. As a result, when the bacteria activate genes to digest lactose they also partially activate genes to digest maltose. The bacteria further demonstrated their anticipatory capabilities by adapting to experimental lab conditions where the sugar maltose was not introduced after lactose. In these instances, the E. coli bacteria eventually stopped activating the genes to digest maltose unless the sugar was actually present.

Learn more about this study, see:

Scientists Show Bacteria Can Plan Ahead (Science Daily)

Biology Basics

Sat, 13 Jun 2009 09:55:36 +0000


Scott Bauer USDA/ARS

What is biology? Simply put, it is the study of life. With that in mind, how do we know if something is living? Is a virus a living thing? What are the characteristics of life? Living organisms have the ability to be organized, take and use energy from the environment, grow and develop, reproduce, respond to stimuli, and adapt to the demands of an environment. Living things include both the visible world of animals and plants, as well as the invisible world of viruses and bacteria.

The foundation of biology as it exists today is based on five basic principles. They are:

Cell Theory: all living organisms are composed of cells. The cell is the basic unit of life.
Gene Theory: traits are inherited through gene transmission. Genes are located on chromosomes and consist of DNA.
Evolution: any genetic change in a population that is inherited over several generations. These changes may be small or large, noticeable or not so noticeable.
Homeostasis: ability to maintain a constant internal environment in response to environmental changes.
Thermodynamics: energy is constant and energy transformation is not completely efficient.

Fingerprint Myth Uncovered

Fri, 12 Jun 2009 16:30:19 +0000


Fingertips David Niblack/Imagebase

For over 100 years scientists have believed that the main purpose of our fingerprints is to improve our grip by increasing friction between our fingers and an object. Researchers have discovered that while fingerprints may be useful for several other functions, they do not improve our grip on smooth surfaces.

While testing the hypothesis of fingerprint friction, the researchers discovered that skin behaves more like rubber than a normal solid. In fact, our fingerprints reduce our ability to grasp objects because they reduce our skin's contact area with the objects we hold. Several other theories have arisen as to why we have fingerprints. Researchers believe they help to improve contact with surfaces in wet conditions, protect our fingers from damage, and even increase touch sensitivity.

Learn more about this study, see:

Fingerprints Do Not Improve Grip Friction (Science Daily)