A man and his wife are both carriers of the recessive allele causing Tay‐Sachs disease. A. What does “carrier” mean in genetics? Why are they important in the high frequency of fatal diseases like Tay-Sachs and Sickle-cell in populations? B. If they have a child, what is the probability that the child inherits the Tay Sachs allele but is not affected? Show your work. C. If they have another child, what is the probability that this child will have Tay‐Sachs disease? D. What cell organelle does not work properly in people with Tay Sachs disorder?

A couple use chorionic villus sampling because the mother is at risk of a genetic disease. The developing embryo has a karyotype of 46+1 (47), with an extra chromosome. What is the diagnosis? 

This is a term used to describe the lack of pleasure from typically pleasurable activities such as eating or listening to music. This is one of the hallmark criteria for Major Depression. 

Some combinations of recessive alleles cause problems so severe that the fetus ceases to develop. Such lethal allele combinations appear to alter Mendelian ratios because

1. Explain how a child could have 3 parents. (2 points max) 2. Summarize 1 of the 2 new studies recently published that use pedigrees as a part of their methods. (2 points max) Note: the maximum points you can receive on the exam is 75 points.    

Mendel’s laws of inheritance derive from

Many people with depression experience this symptom in which they feel as though nothing they do has an impact on the outcome, which leads the person to stop exhibiting various behaviors, such as self-care and socializing. 

The order of events in the cell cycle is

Baby Antoine was born in a remote part of Quebec, Canada. He appeared to be a healthy six‐pound twelve‐ounce baby, except he did not eat well. During the weeks after his birth, he became more and more lethargic (sleepy, moving slowly), and he vomited periodically. His urine smelled of rotten cabbage. Baby Antoine gained only half a pound in six months and doctors had to feed him through a tube into his stomach. He gained weight and strength for a while, but died before he was a year old. It became apparent that other babies in the same area had similar symptoms, and people recalled similar deaths. Some families lost several children to Antoine’s disease. In those families, the parents were normal but about 25% of their children were affected. Specialists concluded that this was a genetic disorder. A. Based on the pedigree and information in the story above, is Antoine’s disease inherited as a dominant or a recessive trait? Explain your answer. B. What are the genotypes of these individuals? III‐J _________ II‐C _________ II‐D _________ C. If individual III-K married their first cousin III-S, what is the probability that they would produce an afflicted child? Show your work and/or calculations (when applicable).

Choose the correct pattern (or mode) of inheritance for the following pedigree: