Regina's Biology Blog

Cell in Mitosis © The Entangled Bank

Researchers have discovered how sister chromatids stay together during mitosis.

Mitosis is a process that enables organisms to grow and reproduce.

During mitosis the genetic material from a parent cell is divided equally between two cells.

The research team from Oxford University has discovered that a protein ring is responsible for holding sister chromatids together until they are ready to be separated into two new cells.

This discovery is a key step to uncovering the mechanisms by which chromosomes separate during mitosis.

By gaining better insight into this process, future treatments for conditions such as Down's syndrome may be developed.

Learn more about this study, see:

• Puzzle In The Control Of Cell Division Unraveled (Science Daily)

Human Ovum and Sperm © Dennis Kunkel

Individual organisms come and go, but, to a certain extent, organisms transcend time through reproducing offspring.

In sexual reproduction, two individuals produce offspring that have genetic characteristics from both parents.

Sexual reproduction introduces new gene combinations in a population.

Reproduction is not a continuous activity and is subject to certain patterns and cycles. Oftentimes these patterns and cycles may be linked to environmental conditions which allow organisms to reproduce effectively.

Cycles and patterns allow organisms to manage the relative expenditure of energy for reproduction and maximize the chances of survival for the resulting offspring.

Researchers have come one step closer to being able to use plants more often as a source for a particular type of medicine.

An important gene has been identified that is involved in the glycosylation process in plants. Glycosylation is a process in which various sugar chains are added to certain proteins.

These sugar chains are important to the development of therapeutic proteins used in medicines.

With this discovery, the researchers are hopeful that they will be able to make adjustments in the glycosylation process to improve the production of therapeutic proteins.

Learn more about this study, see:

• Breakthrough In Plant Medicine Production (Science Daily)

Heart Muscle Cell © Dennis Kunkel

Muscle tissue is made of excitable cells that are capable of contraction. This tissue is the most abundant tissue in most animals.

There are three major types of muscle tissue:

• Cardiac Muscle - found in the heart.
  
• Skeletal Muscle - attached to bones by tendons.
  
• Visceral (Smooth) Muscle - found in various parts of the body such as the arteries and many other organs.

Skeletal muscles are voluntary muscles because animals have control over their contraction.

Visceral muscles are involuntary since, for the most part, they are not consciously controlled.

Learn more about muscles and tissues, visit:

• Animal Tissues

Researchers have discovered two important pathways that control stem cell function. One pathway signals cell repair, while the other inhibits cell repair.

When cells get worn out or damaged, certain biochemical signals trigger adult stem cells to start working to repair tissue.

As we grow older, the stem cells in the older tissue are inhibited by certain chemical signals from reacting as they normally would.

In the study, the researchers discovered that when placed in the proper environment and exposed to the appropriate signals, older tissue can repair itself once again.

This discovery is exciting news because it demonstrates that adult stem cells can be used to revive degenerating tissue and eliminates the controversy and problems associated with embryonic stem cell experimentation.

For additional information, see:

• Stem Cell Researchers Give Old Muscle New Pep (Science Daily)

All animals have common names. These names may be different for the male, female, and young of a species. They may also be different for different groups of animals.

For example, a group of bees is called a swarm and a group of sheep is called a flock.

Common animal group names are different from scientific names. Scientific names are unique to a specific animal and apply to the male, female, and young of the species. Common names are not unique to a specific animal and can change depending on the age or gender of an animal.

Ever wonder what a group of alligators is called? How about a group of frogs? Play the Animal Groups Name Game and learn the names of various animal groups.

More Biology Games:

Baby Animal Name Game
Animal Name Game
Scientific Name Game

Before you eat that big juicy steak or those tasty fries, you may want to think about how it might affect your memory.

A study suggests that a diet high in cholesterol and saturated fat can contribute to memory loss.

Researchers from the Medical University of South Carolina contend that this type of diet leads to inflammation in the brain. It also disrupts certain proteins that are needed in nerve cell function.

Although this study was performed using rodents, the researchers believe that it is very likely that this same phenomenon occurs in humans as well.

For additional information, see:

• Memory Loss Linked To Poor Diet, Study Suggests (Science Daily)

Salmonella Credit: Janice Carr/CDC

The nationwide outbreak of Salmonella in raw red plum, red Roma, and round red tomatoes has caused much concern among consumers.

Salmonella is responsible for millions of foodborne illnesses each year.

In light of this, researchers have announced that they have discovered how Salmonella avoids detection in the body.

Once inside the body, Salmonella bacteria excrete a protein that hampers the body's ability to produce an inflammatory response. This helps the bacterium to avoid detection by the immune system and gives it enough time to reproduce throughout the body.

The protein, AvrA, affects epithelial cells in the wall of the intestines and stomach.

Symptoms of Salmonella infection include nausea, vomiting, abdominal pain, and diarrhea.

For additional information, see:

• Salmonella: Trickier Than We Imagined (Science Daily)

Bacteriophage Structure © Gary E. Kaiser

Bacteriophages are viruses that infect bacteria.

Viruses cannot reproduce or express their genes without the help of a host. Viruses that kill their infected host cell are called virulent.

The DNA in these type of viruses is reproduced through the lytic cycle.

In the lytic cycle, the virus breaks open, or lyses, their host cell, resulting in the destruction of the host.

These animated images reveal the process of the lytic cycle in bacteriophages.

• A bacteriophage attaches to the cell wall of a bacterium.


• The bacteriophage injects its genome into the bacterium.


• The viral genome is replicated.


• Bacteriophages are released by lysis.

Learn more about viruses, see:

• Viruses

Human anatomy is a popular subject for many biology students. Human anatomy deals with body components and body structure. The human body is organized on various levels. Each of these levels builds on the other to comprise an organism.

For example, cells make up tissues, tissues make up organs, organs make up organ systems, and organ systems work together to comprise an organism.

Understanding this concept is key to understanding how the different parts and systems of the body work together to form one organism.

Do you know which organ is the largest gland in the body? Test your knowledge of human anatomy. Take the Human Anatomy Quiz!

Learn more about human anatomy before taking the quiz:

• Organ Systems