Warm Up 11 is due Wednesday April 7, 2004, at 9:30 am Remember...look at the lecture notes and do the readings before (or while) doing the Warm Up. You may need to look terms up in the book's glossary or on the CD (or on google!).
First name :
Last name :
Class Section (1, 2 or 3): (See Oncourse to determine whether you are in 1= A410, 2 = A411, or 3 = A413)
Please enter a nickname (in case your answer is used in class!)
The following three questions refer to material you were to read in preparation for class. These questions require you to write a three or four sentence response. It is OK to answer 'I don't know' - but STATE WHY you are confused! (Don't just say 'I don't know' - you probably DO!) Each WarmUp worth 3 points if answered on time and must be submitted via the web. See notes page for prior Warm Ups and student responses.
QUESTION 1: Achondroplasia is a dominant genetic disorder and causes severe changes in skeletal and bone growth and development, resulting in a dwarf phenotype. People who are not dwarfs - this includes most or all N100 students - are homozygous recessive for this gene (aa). People with achondroplasia (dwarfism) are all heterozygous (Aa). However, no people with dwarfism are homozygous dominant for this trait (There are no people who have the genotype AA). Why do you think the genotype AA is not found is people with dwarfism?
From libo: q1: The genotype AA is not found because If they have AA it is lethal. That means that they will not be alive to find it. THis is because AA results in spontaneous abortion of the fetus. From meg: q1: it is lethal- fatal (spontanious abortion of fetus) anyone who would have AA dies in the womb
From ja: q1: Dwarfism is a disease that affects the growth of the body and limbs. If a fetus has the AA genotype it would affect the growth of limbs and body so much that the fetus would not survive.
QUESTION 2: Allison is driving with her parents, Kate and Bob, when they get in a serious car accident. At the emergency room, her doctor (you) tells Allison that her mother is fine, but her father has lost a lot of blood and will need a blood transfusion. Allison volunteers to donate blood, and you tell her that her blood type is AB. Bob is type O. (1) Can Allison donate blood to Bob? Why or why not? (2) Allison, who is a biology student, begins to wonder if she is adopted. What would you tell her and why?
From 'mos: q2: I am not sure about donating blood, but i would guess that it is not possible for a AB doner to donate to an 0 pacient because there is no genetic simularity between the two types. That being the case i would also think that Allison is indead adopted. Her AB blood reqires IaIb genotype and contains no resesive i allels. If bob was indead her father he would have contributed one resesive i allel to her genotype.
From babes: I not real sure but I think that she would not be able to give blood to her father but he could give blood to her because he is type O and has the recessive gene of AB. She is probably right that she is not related because her father only carries ii and she received Ia Ib.
From Shifty-eyed Swindler: 1. No she can not. Her father can only receive type O blood, since his body would treat any other blood type as 'foreign'. 2. Bob can not be her father. Her father's genotype is ii, so, depending on her mother's blood type, Allison should be either IA i (type A) or IB (type B).
QUESTION 3: Sex linked disorders (carried on the X chromosome) like color blindness, hemophilia, and muscular dystrophy, are frequently passed from carrier mothers to sons, who are affected with the disorder because they have only one X chromosome. However, sometimes females are born with color blindness, hemophilia, or muscular dystrophy. How can this happen?
From Daisy Mae: q3: Daughters can only have these x-linked genetic diseases if her mom carries the disease and her father expresses (is afflicted) with it. A good number of x-linked diseases are not passed on because they are deadly to a father who may or may not make it to an age where he can reproduce. From susie: q3: This can happen if the mother's are carriers of the diseases and if the male has one of the diseases because in order for a girl to inherit one of the diseases there has to be two recessive alleles.
From ed: q3: It happens when mom is a carrier and if dad is color blind
From ardre: q3: If they inherit the allele from both parents, it will be expressed. This is rare; the girls will in most cases be a carrier.
q4: It is crazy how things work and how each one of us are created and how each one of us is quite different all because of genetics. q4: It makes my head hurt to think about it. q4: I find this confusing and understanding the logic that determains the charastic that we are liiking and relating the Homo..../hetro... aspects of my chart results. I will keep working on it... q4: This stuff is interesting but really confusing!!!! I hope will talk more about the second and third questions in this warm up in class Wednesday. I really had a hard time figuring out the answer. q4: This is very interesting. You need to keep up with notes and lectures or you will be left behind. This is not a subject you could sit down at home and figure out on your own, not for me anyway. q4: Is there any trick or memory device to remembering which autosomal disorders are dominant, recessive, or related to the sex chromosomes? Thanks q4: I am a camp counselor at the muscular dystrophy camp every summer, and I see lots of children with this genetic disorder. It is amazing that there are so many different types of muscular dystrophy. And I have noticed that there are more males than females there. Interestingly enough, two of the girls in my cabin are identical twin girls who have a severe form of muscular dystrophy. I guess I never thought of genetic disorders and how they affect twins. q4: I think the material we have been covering is very interesting. I find this stuff more useful to me in everyday life.