Answer;
C. His mother carried at least one allele for that trait
Explanation;
-Men have a single allele of each gene on the X chromosome, inherited from their mother, and a single allele of each gene on the Y chromosome, from their father.
-A sex-linked trait is a trait that is controlled by a gene or an allele located on the sex chromosome.
-X-linked traits are maternally inherited from carrier mothers or from an affected father. Each son born to a carrier mother has a 50% probability of inheriting the X-chromosome carrying the mutant allele.
<span>C. Gametes are the sex cells, and each (sperm and ovum) contain half of the parent's genetic material. These cells will fuse to produce a zygote, which will usually contain the full number of genes required by an organism to live. If there is a chromosomal abnormality, such as a gamete with an extra chromosome, the offspring can either die in development or sometimes be born with physiological and/or developmental difficulties. An example of this phenomenon is trisomy 21, also known as Down Syndrome, in which the 21st chromosome bears 3 copies instead of the regular 2.</span>
main engines of creation of the proteins on which the body depends.
The progeny has one set of genes from its mother and another set from its father.
A paleontologist can use radiometric dating (also known as carbon dating), to determine the age of a fossil. They do this by measuring the decay of isotopes in either the fossil itself or the rocks associated with it. A carbon-14 isotope takes about<span> 5,730 years to halfway decay, knowing this information paleontologists can date a fossil by how long the fossil has been decaying with the use of special tools.
http://hyperphysics.phy-astr.gsu.edu/hbase/Nuclear/cardat.html
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