There are about 35,000 genes in the nucleus of human body cells. These genes are packaged into 23 pairs of chromosomes, numbered 1 through 22, with the 23rd pair being the sex chromosomes (X and Y). Each of the genes has a specific role in the...
Two types of cell division exist: meiosis, the division of sex cells that reduces the number of chromosomes (genetic material) by half, and mitosis, which is the type that most people refer to when speaking of cell division. Mitosis, the...
Klinefelter's disease, also known as Klinefelter's syndrome or XXY male, refers to a common genetic disorder where males have an extra X chromosome (genetic material) in each of their cells. According to the Mayo Clinic, Klinefelter's syndrome can...
The adrenal glands are an important part of the endocrine system; they make hormones that affect the rest of the body. Adrenal hypoplasia is a disorder in which the adrenal glands do not develop properly, causing them to make low levels of...
Every human being has 46 chromosomes, including two chromosomes (X ,Y) that determine gender. The Y chromosome is unique to males. Inheriting an X chromosome from the mother and a Y chromosome from the father makes the child male. Because the Y...
A hiatal hernia is a condition that occurs when the upper portion of the stomach protrudes into an opening of the diaphragm called the hiatus. When this occurs, stomach acid leaks back up into the esophagus, causing bothersome symptoms of acid...
Q. What is human sperm made up of? A. Sperm is found inside seminal fluid (semen). Semen is a mixture of sperm and the secretions of the seminal vesicles, prostate gland and the bulbourethral glands. Sperm make up only about 5 percent of semen,...
Chemotherapy is the use of chemical agents--drugs--to target and kill the rapidly dividing cells of cancer. These medications are highly effective on cancer cells but also affect normal cells, especially the rapidly dividing cells of the...
Fibroids can have significant effects that interfere with daily life. Many women worry that invasive surgery is their only option, but new understanding about the causes of fibroids has led to treatment strategies that involve hormones and...
Each cell within the human body contains DNA, made up of a sequence of billions of chemicals called base pairs. The sequence of specific base pairs codes for thousands of genes found on two sets of 23 chromosomes--large pieces of DNA, each...
Anorexia nervosa refers to an eating disorder characterized by starvation or eating far fewer calories than the body needs to properly function and survive. Although some people turn to anorexia in their attempt to lose weight, for many others the...
When a doctor needs to assess the condition of your liver, he orders a panel of laboratory tests. The panel typically includes several liver enzymes. In patients with Turner's Syndrome, the liver enzymes are often elevated. The reasons for these...
The first five years of a child's life mark an important time for physical development. Your child refines his motor skills and develops an active lifestyle during this time. Understanding physical development in your preschooler will help you...
According to the National Institute of Neurological Disorders and Stroke, Moebius syndrome is a rare birth defect that affects the sixth cranial nerve, which moves muscles of the face, and the seventh cranial nerve, which moves eyes side-to-side....
Genetic diseases occur because of abnormal genes or chromosomes. Causes of genetic diseases include mutated genes, chromosome duplication, missing chromosomes and a portion of a chromosome erroneously attaching to another chromosome. Some genetic...
Down syndrome, a genetic defect that is beyond the control of the parent, occurs when there is an extra copy of the 21st chromosome in all or some of the cells in your body. Chromosomes are structures made from your unique DNA or genetic...
The whole of a person's DNA, called the genome, consists of components called nucleotide bases. The bases link together to form a series of base pairs, and the sequence of base pairs codes for thousands of genes required for growth and survival....
Blood cancer is characterized by the abnormal growth of red blood cells, bone marrow cells or cells of the lymphatic system. Blood cancer is divided into three subcategories: leukemia, lymphoma and multiple myeloma. Leukemia is a type of cancer...
Sexual FAQs Q. What is human sperm made up of? A. I'll assume you are asking about sperm plus the seminal fluid (a.k.a. semen) that contains the sperm. Each sperm or spermatozoon (spermatozoa is the plural) is actually made up of three parts:...
Acute lymphoblastic leukemia, which is also known as ALL, is a disorder that arises from some of the cells in the bone marrow. This type of cancer causes the bone marrow to make too many lymphoblasts, which are cells that are precursors to white...
Triple X syndrome is a genetic disorder in which a girl has three X chromosomes instead of two. Triple X occurs once in every 1,000 female births. However, doctors believe many girls with Triple X go their lifetime undiagnosed. The major...
The U.S. National Library of Medicine's Genetics Home Reference website says Triple X Syndrome, also known as Trisomy X or Trisomy 47, is a genetic condition where females have three X chromosomes instead of two. The European Journal of Human...
DNA is made up of a series of chemicals called nucleotide bases, which link together to form strands of DNA. These strands pair with other DNA strands to form a structure called the double helix. The sequence of nucleotide bases comprises...
Down's Syndrome is caused by an extra copy of the 21st chromosome, which is a portion of genetic material in the makeup of the human body that controls genetic development. Down Syndrome, according to the National Down Syndrome Society, affects...
DNA provides the blueprint for life: it codes the information required for cells to generate the compounds required for growth, development and metabolism. Genetic diseases may develop due to abnormalities or deletions of single genes, or large...
Dr. Mehmet Oz, known on television as Dr. Oz, leads the Cardiovascular Institute and Complementary Medicine Program at New York Presbyterian Hospital, according to Oprah.com. Dr. Oz is regarded as the health expert on the Oprah Winfrey Show and...
Huntington's disease is a genetic disorder that results in degeneration of neurons in certain areas of the brain. Early signs include clumsiness, uncontrolled movements and difficulties maintaining balance. Huntington's progresses over years and...
Your genes, also known as deoxyribonucleic acid (DNA), contribute to defining you as a person. They determine your appearance, your personality and your health condition. Sometimes, environmental or hereditary factors can play a role in...
Genetic diseases result from mutations or abnormalities on chromosomes or genes. Some ethnic groups are at higher risk for some genetic diseases than others, but the diseases can occur in any group, according to the Genetic Disease Foundation....
