The female ova (egg) gamete is homogametic, in other words, all the cells carry the same X sex chromosome. However the male sperm gamete is heterogametic because approximately half of them contain the X chromosome and approximately half of them contain the Y chromosome. After implantation occurs, the presence of the Y chromosome stimulates the secretion of testosterone in the embryo. The presence of testosterone results in the development of male genitalia during the fifth to seventh week of gestation. In the absence of the Y chromosome, the rudimentary reproductive organs progress to develop into female genitalia.
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Jumo Health answeredSee All 2 AnswersStem cell transplantation is when a person gets healthy, new stem cells to replace unhealthy bone marrow and blood cells. This is called a stem cell—or bone marrow—transplant.
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An allele is an alternative form of a gene that is located at a specific position on a specific chromosome. Alleles contain the DNA coding which determines the traits that can be passed on from parents to offspring Organisms have two alleles for each trait. When the alleles of a pair are heterozygous one is dominant and the other is recessive. The dominant allele is expressed and the recessive allele is masked. Therefore, heterozygous individuals have two different alleles for a single trait while homozygous individuals have two identical alleles for a single trait.
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Brigham and Women's Hospital answeredSee All 2 AnswersChromosomes are the structures in our cells that contain our genetic information. Humans have two sets of 23 chromosomes, for a total of 46. Chromosomes 1-22 are called autosomes and are numbered 1-22. The last pair of chromosomes is the "sex chromosomes." There are two types of sex chromosomes: X and Y. Females have two X chromosomes and males have one X and one Y. Nearly all our cells contain the full complement of 46 chromosomes. However, egg and sperm cells each only contain one set of chromosomes (23) so that when they meet at fertilization the resulting embryo will have a total of 46 chromosomes. -
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Brigham and Women's Hospital answeredA mutation can either be inherited from a parent or may arise in an affected person for the first time -- this is called a spontaneous or new mutation. However, the spontaneous mutation typically occurs at such an early stage of development that it is present in all the cells, including sperm and egg cells. This means that the mutation can then be passed to future generations. If the mutation occurs later in development it may not be present in all the cells -- this is called mosaicism. The risks to future generations are less clear in these situations.
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Jumo Health answeredSee All 4 Answers
Genes are the instructions for making human bodies, including the machines inside the body's cells. Different genes determine different things about the body, like hair and eye color, and height and build. People get genes from their parents, one set from their mother and one set from their father. That's why most people look a bit like their mother and a bit like their father.
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Largo Medical Center answeredSee All 2 AnswersThe advantage of using stem cells in spinal surgery is that these are the body's own natural growth factors and growth cells that can promote bone growth. With stem cells, we see much more successful rates of fusion.
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Multiple Sclerosis Foundation answeredThe following diseases and medical conditions are often associated with genetic risk:- Cancer
- Heart disease
- Diabetes
- Dementia
- Asthma
- Arthritis
- Mental illness
- High blood pressure or high cholesterol
- Stroke
- Kidney disease
- Alcoholism or other substance abuse
- Vision or hearing loss
- Learning disabilities
- Developmental disabilities
- Miscarriage, stillbirth, birth defects, or infertility
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Dr. Mehmet Oz, MD , Cardiology (Cardiovascular Disease), answeredHere's how cells become exhausted and die: At the end of each chromosome inside the nucleus of a cell are stretches of deoxyribonucleic acid (DNA) called telomeres. Each time a cell dies the telomeres get shorter until they get so short the cell can no longer divide and dies, a process associated with aging.
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Dr. Mehmet Oz, MD , Cardiology (Cardiovascular Disease), answeredThe following can help prevent cellular exhaustion (cellular death):
- Try astragalus, a medicinal Chinese plant shown to help rebuild genes by boosting the enzyme telomerase. Along with ginseng, astragalus is a member of the adaptogenic herb family that also helps reduce stress.
- Stand up for 10 minutes a day. Many of us have difficulty finding time to exercise. If you can't get in your daily walk, you certainly can make time to stand up for 10 minutes a day, an activity shown to dramatically help rebuild your genes.
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