Fall 2016 : Biol 105 Exam 4 Essay Questions Essay

Since the first essay question consists of three parts, I will break them down and address them individually, starting with the first.

Heterozygous females have different LWS genes on their X-chromosomes. Jacobs states that “the early developmental process of random X-chromosome inactivation results in a retina that contains three classes of cone pigments; since there are only three possible pairings, there are also

An example of a recessive x-linked disorder is fragile x-syndrome or FXS. Fragile x-syndrome affects a person’s behavior, learning, intellectual, as well as physical characteristics. Fragile x-syndrome is more likely to affect males over females and does not shorten their life expectancy. Males who have FXS can have ADD or ADHD, autism, aggression and other behavioral traits. Men can have physical alterations such as a long face, large ears, and flat feet. Women who have FXS can experience the same behavioral traits but are usually milder in comparison to men. The same is shown through the facial features for women (National Fragile X Foundation,

If the mutated gene attaches itself to one of the sex X chromosomes, then the condition will be considered as X-linked. If one of the altered gene copies is capable of causing the condition in each of the individual’s cells, then the Fragile X syndrome condition is referred to as dominant. However, it has been discovered that sons will never inherit the gene from fathers as the X chromosomes are the only genes responsible for the genetic condition. Sons can only inherit the genes from their mothers (McLennan, 2011). This fact is very unusual considering that males are more severely affected by the conditions than their female counterparts. It can be said that some females act as carriers of this gene which then establishes itself as dominant in males, whereas in females it might be recessive. With the prevalence of this condition, it ranks as the most common inherited genetic and intellectual

Autosomal recessive inheritance implies that the quality is situated on a single autosome of the autosomes. This implies men and women are similarly influenced. "Recessive" implies that two duplicates of the gene are important to have the characteristic, one acquired from each parent. An individual who has only a single recessive gene is know a "carrier" for this gene or infection, yet they don't have any medical issues from "carrying" one duplicate of the gene. Majority of the individual are not aware that they are carry a heterozygous genetic factor for an illness until they have a baby with it. [1] When mother and father have had a child with a recessive trait or illness, there is a one out of four, or 25% chance, with each consequent pregnancy,

X-linked recessive don’t affect females because females have two X chromosomes. However, females who inherit the mutation will become carriers. If a male inherits the mutation from his mother, he will not have a normal copy of the gene and will develop the condition. When a mother is a carrier of an X-linked mutation, each daughter will have one in two (50%) chance of becoming a carrier and each son will have one in two (50%) chance of inheriting the condition. When a father has X-linked condition, his sons will not be affected because he will pass on a Y-chromosome. However, any daughters he has will become carriers of the mutation. The genetic conditions inherited include Duchenne muscular dystrophy, haemophilia and fragile X syndrome.6

The authors in paper one studied the genetic etiology of patients with disorders of sex development (DSD) (Kim et al, 2017). DSDs make up a congenital condition where the development of gonadal, chromosomal and anatomical sex is atypical (Kim et al, 2017). They

3. Please ensure that you include the following information with your assignment: your name, your

A sex-linked trait is one that is associated with the genes on the sex chromosomes of an individual; the non-homologous X and Y chromosomes. A trait related specifically to the X chromosome (X-linked) can be passed to females and males since each gender will inherit at least one X chromosome from his/her mother. However, only males can inherit traits linked to the Y chromosome since those inheriting a Y chromosome are inherently male.

X-linked dominant inheritance is a mode of genetic inheritance by which a dominant gene is carried on the X chromosome. X-linked dominant traits do not necessarily affect males more than females (unlike X-linked recessive traits). The exact pattern of inheritance varies, depending on whether the father or the mother has the trait of interest. All daughters of an affected father will also be affected but none of his sons will be affected (unless the mother is also affected). In addition, the mother of an affected son is also affected (but not necessarily the other way round). Examples of X-linked dominant conditions include Rett syndrome, Fragile X syndrome, and Alport

Due to being present in a female, the subject in question, this gene is not Y-chromosome linked. Other evidence of this not being a Y-linked trait is the presence of males within the pedigree who do not show signs of the trait as shown with the subject's brothers and her uncle. The pedigree would go from I-2, II-3 and III-3 showing the trait to I-2, II-2, II-3, III-1 and III-2 showing the

Whether we are born males or females is determined by the X and the Y chromosomes. A person who gets two X chromosomes forms as a female while a person who gets both an X and a Y forms as a male. So I have both an X and a Y chromosome while my three sisters all have two X chromosomes. Some human disorders are sex linked. Hemophilia and colorblindness are due to recessive alleles. A male who receives a recessive allele from his mother will have the disorder however for a female to have the disorder both the mother and father must pass on the recessive allele.

What is an X-linked recessive trait? Well it means that the mutation on the gene is carried on the X chromosome, causing it to be expressed in males who are heterozygous for gene mutation, and females who are homozygous for gene mutation. It is explained that men are affected and women are would be carriers for X-linked recessive trait. But it is rare for women to be affected by this mutation.

Please describe your academic preparation in Biology and Math in 1000 characters or less. In addition to courses, you should describe relevant professional or extra-curricular experiences. While at OSU, I have completed Pre-calculus and am currently enrolled in Calculus. I am also currently taking an EEOB course, Bio-Invasions. This course views ecological and evolutionary concepts through the lens of non-native introduced species.

X-linked disorders are also called sex linked diseases are passed down through a person parents through one of the X or Y chromosomes. X and Y are sex chromosomes. The prevailing abnormal gene from one parent causes disease even though the matching gene from the other parent is normal. This abnormal gene dominates the others. However in recessive inheritance, both matching genes have to be abnormal to cause a disease. If only one gene in the pair is abnormal, the disease does not occur or it in a mild form. People who have one abnormal gene and have no symptoms are called a carrier. Carriers can pass abnormal genes down to their children. Here are some X-linked disorders below.