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The Application of Knowledge on Mitosis in Cloning

Cloning - Process of producing clones or genetically identical organisms through asexual reproduction.

Cloning - 1. Plant
               - 2. Animal

Plant 

Animal

The Similar Between Mitosis And Meiosis

The Difference Between Mitosis and Meiosis

Mitosis & Meiosis

Meiosis and mitosis are quite confused . Let us watch this video .
Can you tell me how to remember mitosis and meiosis?

They are both critical terms in cellular biology.

I know that much. But I need to know the differences between the two.

Mitosis and meiosis are both ways cells can divide and reproduce.

That's why I need to know the difference.

Mitosis is when a cell divides and creates two identical copies.

Kind of like a copier.

Except it takes the original sheet and gives you two clones. Actually, you can think of mitosis as natural cloning.

What then is meiosis?

Meiosis can be thought of me-genesis. It is how you were made, hopefully.

That was covered in sex education, not cellular biology.

Meiosis is when a germ cell fissions to create sex cells. This happened in both your parents, and their germ cells eventually combined to create you.

This is interesting and all, but what is the difference on a cellular level.

Meiosis creates germ cells or sex cells with half the chromosomes needed to make someone or something. It creates a cell that is half of a new whole.

Whereas mitosis creates two new cells that do not combine.

Mitosis creates two new cells with all the chromosomes of the original, baring a genetic error. Meiosis creates new cells that have half the chromosomes of the original.

Maybe I should remember it as mitosis is for bacteria, and meiosis is for advanced life like me.

Now your body has mitosis, too, such as when cells divide and reproduce to replace dead cells. The only place we see meiosis is the creation of new people.

So meiosis is only for the creation of a mini-me.

And mitosis is for minor repairs of your body so you don't fall apart or ossify.

How Chromosome Abnormalities Happen: Meiosis, Mitosis, Maternal Age, Environment

How do chromosome abnormalities happen?

Chromosome abnormalities typically occur as a result of errors in one, or more, of the following: meiosis, mitosis, maternal age, or environment.

Meiosis

Chromosome abnormalities usually happen as a result of an error in cell division. Meiosis is the name used to describe the cell division that the egg and sperm undergo when they are developing. Normally, meiosis causes a halving of chromosome material, so that each parent gives 23 chromosomes to a pregnancy.

The result is an egg or sperm with only 23 chromosomes. When fertilization occurs, the normal 46 total number of chromosomes results in the fetus. If meiosis does not occur properly, an egg or sperm could end up with too many chromosomes, or not enough chromosomes. Upon fertilization, the baby could then receive an extra chromosome (called a trisomy), or have a missing chromosome (called a monosomy).

While pregnancies with a trisomy or a monosomy may go to full-term and result in the birth of a child with health problems, it is also possible that the pregnancy may miscarry, or that the baby is stillborn (not born alive), because of the chromosome abnormality. In studies of first trimester miscarriages, about 60 percent (or more) are chromosomally abnormal. In studies of babies who are stillborn, 5 to 10 percent have a chromosome abnormality.

Mitosis

Mitosis is the name used to describe the cell division that all other cells, besides the egg and sperm, undergo when they are developing. Normally, mitosis causes a duplication, followed by a halving of chromosome material, so that each cell doubles the number of chromosomes to 92, and then splits in half, so that the normal total of 46 is resumed. Mitosis begins in the fetus after fertilization.

This process repeats itself, until the entire baby is formed. Mitosis continues throughout our lifetime, to regenerate new skin cells, new blood cells, and other types of cells that are damaged or that simply die off.

During pregnancy, an error in mitosis can occur, just like the error previously described in meiosis. If the chromosomes do not split into equal halves, the new cells can have an extra chromosome (47 total) or have a missing chromosome (45 total). This is another way a baby can be born with a chromosome abnormality. Errors in mitosis are responsible for some cases of mosaicism.

Maternal age

When a mother will be 35 years of age at delivery (or older), she may be referred for genetic counseling or for prenatal diagnosis, such as an amniocentesis because of her age. There is a fundamental difference in the way that eggs and sperm are made. Women are born with all the eggs they will ever have, and they begin to mature during puberty. Over time, there are fewer and fewer eggs available in the ovaries. If a woman is 35 years old, the eggs in the ovaries are also 35 years old. The risk for a baby to be born with a chromosome abnormality increases with the age of the mother. Some scientists and doctors believe that this is because the eggs are aging, and may have the incorrect number of chromosomes at the time of fertilization. Errors in meiosis may be more prone to happen as a result of the aging process.

Men, on the other hand, produce new sperm continually. Therefore, if a man is 35 years of age, his sperm are not 35 years of age. However, recent studies have shown that men over the age of 45 years may have an increased risk for new (de novo) autosomal dominant conditions in their children.

Environment

Many parents who have a child with a chromosome abnormality wonder whether the various environmental exposures they have had over the years contributed to having a baby with a chromosome abnormality. To date, there is not anything specific in the environment, such as X-rays, medications, foods, and microwave ovens, that has been found to be the reason for a baby to be born with a chromosome abnormality. In fact, most parents who have a child with a chromosome abnormality, when compared to those parents who do not have a child with a chromosome abnormality, have no difference in habits, lifestyles, or environmental exposures.

There is some evidence accumulating that how a woman's body processes the B vitamin folic acid, may have something to do with why chromosome abnormalities happen. Those women who do not process this vitamin completely, may have a predisposition to having a child with a chromosome abnormality. This has not been proven, but knowing that this is a possibility gives women of reproductive age a good reason to take a multivitamin with folic acid (before becoming pregnant) and prenatal vitamins during a pregnancy to reduce this potential risk.

12 chromosomal disorders you may not have heard of

1. Wolf-Hirschhorn syndrome

Description: Wolf-Hirschhorn syndrome is caused by the deletion of the distal short arm of chromosome 4. The disorder’s major features include a characteristic facial appearance, delayed growth and development, intellectual disability, and seizures.
Organizations promoting awareness: The Real Story About Wolf-Hirschhorn Syndrome
In the news: Living With Wolf-Hirschhorn Syndrome

2. Jacobsen Syndrome

Description: Jacobsen syndrome, also known as 11q deletion disorder, results from a loss of genetic material from the end of the long arm of chromosome 11. Signs and symptoms of this condition vary, but most individuals experience delayed development in motor skills and speech, cognitive impairments, learning difficulties, and some behavioral problems.
Organizations promoting awareness: 11q Research & Resource Group
In the news: Thousands raised for Jacobsen Syndrome

3. Angelman syndrome

Description: Angelman syndrome (AS) is an example of genomic imprinting, where the deletion or inactivitation of genes on the maternally inherited chromosome 15 causes the paternal copy, which may be of normal sequence, to be imprinted and silenced. AS is characterized by intellectual and developmental delays, sleep disturbances, seizures, and jerky movements, but also frequent laughter or smiling and usually have a happy demeanor.
Organizations promoting awareness: F.A.S.T &  Angelman Foundation, Inc.In the news: In Depth: Angelman Syndrome

4. Turner syndrome

Description: Turner syndrome (TS) occurs when one of the two X chromosomes in females is either missing or incomplete. The most common symptoms are short stature and gonadal dysgenesis, which can cause incomplete sexual development and ovarian failure and infertility. As of right now, there is no known cause of TS.
Organizations promoting awareness: Turner Syndrome Society of the US
In the news: Family spreads awareness of Turner syndrome

5. 22q11.2 deletion syndrome

Description: 22q11.2 deletion syndrome is caused by the deletion of a small piece of chromosome 22 near the middle of the chromosome. Because signs and symptoms of 22q11.2 deletion syndrome are varied, different groupings of symptoms were once described as completely separate conditions, named DiGeorge syndrome, velocardiofacial syndrome, and conotruncal anomaly face syndrome.
Organizations promoting awareness: The International 22q11.2 Deletion Syndrome Foundation, Inc.
In the news: 22q11.2 deletion syndrome conference to bring together researchers, educators, families

6. Triple X Syndrome

Description: Triple X Syndrome is characterized by an extra X chromosome in each of a female’s cells. It does not cause any unusual physical features but is associated with the increased risk of learning disabilities and delayed development of speech and language skills.
Organizations promoting awareness: Triple X Syndrome
In the news: What Is Triple X Syndrome? What Causes Triple X Syndrome?

7. Williams Syndrome

Description: Williams syndrome is caused by a deletion of genetic material from portions of the long arm of chromosome 7, a region that consists of more than 25 genes. Researchers have identified a few of the specific genes related to Williams syndrome, but the relationship between most of the genes in the deleted region and the symptoms of Williams syndrome is still unknown.
Organizations promoting awareness: Williams Syndrome Association
In the news: Williams syndrome shows gene-behavior links: Key to autism?

8. Cri du Chat Syndrome

Description: Cri du Chat syndrome results from missing a piece of chromosome 5. Symptoms include a high-pitched cry that sounds like a cat, downward slant of the eyes, partial webbing or fusing of fingers or toes, and slow or incomplete development of motor skills.
Organizations promoting awareness: Five P Minus Society
In the news: ‘Cat Cry’ Syndrome Often Undiagnosed

9. Trisomy 13/Patau syndrome

Description: Trisomy 13, also called Patau syndrome, is a disorder in which an individual has three copies of genetic material from chromosome 13, rather than two. It can occur in three forms: Trisomy 13, which has a third chromosome 13 in all cells; Trisomy 13 mosaicism, which has a third chromosome 13 in some cells; and partial Trisomy, which has the presence of part of an extra chromosome 13 in the cells.
Organizations promoting awareness: Living With Trisomy 13
In the news: Sequenom Validates MaterniT21 for Trisomy 18 and 13 Detection

10. Trisomy 18/Edwards syndrome

Description: Trisomy 18, or Edwards syndrome, occurs when a person has a third copy of material from chromosome 18 instead of the usual two copies. Some symptoms include clenched hands, feet with a rounded bottom, mental deficiency, underdeveloped fingernails, and an unusual shaped chest.
Organizations promoting awareness: Trisomy 18 Foundation
In the news: Baby Jalyssa’s Story: Fighting The Odds, Living With Edward’s Syndrome

11. Cat eye syndrome

Description: For individuals with cat eye syndrome, the short arm (known as 22p) and a small region of the long arm (22q) of chromosome 22 are present three or four times, rather than twice. Characteristic features of the  disorder include mild growth delays before birth, mild mental deficiency, and malformations of the skill and facial region, the heart, the kidneys, and/or the anal region.
Organizations promoting awareness: Support for Disorders of Chromosome 22
In the news: Blog: “Our Journey with Cat Eye Syndrome”

12. Trisomy 16

Description: Full Trisomy 16 occurs when an individual has three copies of chromosome 16 instead of the usual two and is the most common chromosomal cause of miscarriage during the pregnancy’s first trimester. Mosaic Trisomy 16 is a rare disorder in which an extra chromosome 16 is present in some cells, but not all. Some common symptoms include intrauterine growth retardation (IUGR) and congenital heart defects.
Organizations promoting awareness: Disorders of Chromosome 16
In the news: Trisomy 16: the Leading Cause of Miscarriage