Sexlinked traits follow a different pattern of inheritance than a non-sex linked trait because of the size difference between the X and y chromosomes.
Think about non-sex chormosomes as being the same size, each having the exact same number of genes in the same postions (loci). This means that a person has to have two copies of the recessive genes (one on each homolog of that chromosome) before the trait will be expressed.
Lets say A is normal (dominant) and a is abnormal (recessive).
People who are aa have the abnormal condition and people who are AA or Aa are normal. The normal ratio is 1 AA:2 Aa:1 aa if both parents are Aa. There is a 25% chance that a child will inherit two abnormal genes and the chance of any sex child will be so affected is exactly the same.
When a recessive trait is located on the X chromosome only a female with two X chromosomes has the same number of genes on each X chromosome (the two X chromosomes have the same inheritance behavior as a homolog chromosome in females). In males who inherit the much smaller y chromosome there are many genes on the X chromosome that do not have a matching gene on the y chromosome. This means that recessive traits on the X chromosome that have no matching genetic material on the y chromosome will always be expressed.
So, lets say that there is a family where the mother is Aa and the father (who only has one allele on the y chromosome is A. (A is normal and a is abnormal).
None of the daughters produced can be aa, because the father will always pass A. Daughters will only be Aa or AA.
Sons on the other hand, will get either A or a from the mother and, since the y chromosome has no genetic material at this gene locus the boys will be A normal or a affected at in a 1:1 ratio.
If the father is a on his X chromosome, and the mother is AA 100% of the daughters will be carriers (Aa) and all the sons will be normal (A-).
Polygenic inheritance includes traits coming from one source. Mendel described traits as dominant or recessive and that determination created the charts determining the offspring outcome.
Omg i have the exact question on my packet....
Males and females have different sex chromosomes.
Breeding of parents and f1 offspring do not follow simple Mendelian patterns. Some simple polygenic traits (two gene loci multiple alleles at one locus) may appear to follow mendelian patterns...such as base coat color in horses. Multiple other dilution alleles at various loci modify the base coat color. More complex interactions between a series of genes become even more complex and sometimes no offspring of 2 parents that have the desired characteristic are produced in the F1 generation.
DNA Fingerprint
There are lots of ways. A simple way is to do a Punnett Square. It's useful in studying independent inheritance patterns (multiple traits that are not on the same chromosome).
Genes
All traits are inherited through patterns found by Mendel.
All traits are inherited through patterns found by Mendel.
Polygenic inheritance includes traits coming from one source. Mendel described traits as dominant or recessive and that determination created the charts determining the offspring outcome.
He is known as the father of genetics. He crossed pea plants to determine the patterns of inheritance for certain traits.
Omg i have the exact question on my packet....
Males and females have different sex chromosomes.
A pedigree chart is a tool used to trace traits through generations in a family. It displays the inheritance pattern of specific traits or conditions, helping to analyze how they are passed down from one generation to the next. This tool is commonly used in genetics and hereditary studies to understand patterns of inheritance.
males and females have different sex chromosomes
Gregor Mendel observed that traits in pea plants were passed down from generation to generation in predictable patterns. He discovered the principles of inheritance, including the idea that traits are determined by discrete units of inheritance, now known as genes. Mendel's work laid the foundation for the field of genetics.
A pedigree provides a visual representation of genetic relationships and patterns of inheritance within a family or group of individuals, making it easier to trace specific traits or genetic conditions across generations. It also allows for quick identification of patterns of inheritance such as autosomal dominant or recessive traits. In contrast, a written passage may not convey this information as clearly or concisely.