How would the extra chromosome affect the male offspring produced by the gamete ?\?
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For genes on autosomes, we all have two copies—one from each parent. The two copies may be the same, or they may be different. Different versions of the same gene are called “alleles” (uh-LEELZ). Genes code for proteins, and proteins make traits.* Importantly, it’s the two alleles working together that affect what we see—also called a “phenotype.” Show Female pigeons (ZW) have just one Z chromosome, and therefore just one allele for each of the genes located there. One gene on the Z chromosome affects feather color; three different alleles make feathers blue, ash-red, or brown. In a female bird (ZW), her single color allele determines her feather color. But in males (ZZ), two alleles work together to determine feather color according to their dominance. That is, 'ash-red' is dominant to 'blue', which is dominant to 'brown'. Having two copies of a gene can be important when one copy is “broken” or defective. A functional second copy can often work well enough on its own, acting as a sort of back-up to prevent problems. With sex-linked genes, male mammals (and female birds) have no back-up copy. In people, a number of genetic disorders are sex-linked, including Duchenne muscular dystrophy and hemophilia. These and other sex-inked disorders are much more common in boys than in girls. Red/green colorblindness is also caused by a defective gene on the X-chromosome. You need at least one working copy of the gene to be able to see red and green. Since boys have just one X-chromosome, which they receive from their mother, inheriting one defective copy of the gene will render them colorblind. Girls have two X-chromosomes; to be colorblind they must inherit two defective copies, one from each parent. Consequently, red-green colorblindness is much more frequent in boys (1 in 12) than in girls (1 in 250). *Some genes code for functional RNAs, which also influence our traits.  The differences in sex chromosomes between males and females leads to specific inheritance patterns for sex-linked genes. (Above) Female pigeons inherit their color allele from their father. Males inherit one allele from each parent. In humans (below), the pattern is reversed.
Understandings: • Crossing over and random orientation promotes genetic variation • Fusion of gametes from different parents promotes genetic variation The three main sources of genetic variation arising from sexual reproduction are:
Crossing Over Crossing over involves the exchange of segments of DNA between homologous chromosomes during prophase I
Random Orientation When homologous chromosomes line up in metaphase I, their orientation towards the opposing poles is random The orientation of each bivalent occurs independently, meaning different combinations of maternal / paternal chromosomes can be inherited when bivalents separate in anaphase I
The fusion of two haploid gametes results in the formation of a diploid zygote
Would the extra chromosome affect the male offspring produced by the gamete?If during the production of male gametes an error in meiosis occurred, sperm containing both an X and a Y chromosome could be produced. How would the extra chromosome affect the male offspring produced by the gamete? The male offspring would have full-color vision, because of the presence of the extra X chromosome.
What happens if you have an extra chromosome?For example, an extra copy of chromosome 21 causes Down syndrome (trisomy 21). Chromosomal abnormalities can also cause miscarriage, disease, or problems in growth or development. The most common type of chromosomal abnormality is known as aneuploidy, an abnormal chromosome number due to an extra or missing chromosome.
What would be the cause for a gamete to have an extra chromosome?An error in meiosis (called a non-disjunction event) causes the gamete to have an extra copy of a chromosome, and the resulting fertilized egg has a total of 47 chromosomes. It is also possible for a non-disjunction to happen after fertilization (about a 1-2% chance).
What will happen if there will be an extra chromosome in the human cell making it 47?Humans have 23 pairs of chromosomes. A trisomy is a chromosomal condition characterised by an additional chromosome. A person with a trisomy has 47 chromosomes instead of 46. Down syndrome, Edward syndrome and Patau syndrome are the most common forms of trisomy.
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