[HLTH 101] - Final Exam Guide - Everything you need to know! (77 pages long)
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Roger Maxwell is very health-conscious. He runs, swims, and hikes; follows a lowcarbohydrate diet; and generally feels great. He sees a physician when he needs to, in addition to annual physical exams at the large company where he is an engineer. He'd never allow himself to get so out of shape that heart disease would be a risk. Because of his strict adherence to this healthy lifestyle, Roger is surprised when a medical intern, gazing at his yearly elecfrocardiogram (ECG) at his work physical, clearly picks up on something.
"What? What are you looking at?" Roger blurts out while buttoning up his shirt.
"Oh, it's probably nothing." But she doesn't look like it's probably nothing.
"The heart murmur? My mom's been telling me about it since childhood. Not a big deal. The doctors called it something last year, something I never heard of." "Did you check it out?" asks the intern.
"Nah. It wasn't bothering me, so I forgot about it. Why? What's wrong?"
"Well, maybe you should ask the doctor to explain it again and suggest what to do."
"About what?"
| "The doctor will explain it. Please don't worry, though," says the intern as she rushes off to the next patient. Roger's electrocardiograms had in fact been showing that he has had long QT syndrome, and not a heart murmur, for many years. The doctor explains that this is a problem with the heart's rhythm, and not its valves. Roger goes home and Googles long QT syndrome right away. What he finds concerns him enough to alert his relatives. Long QT syndrome is a lengthening in the time that it takes the ventricles (the lower two heart chambers) to recover after a contraction, called the QT interval on an electrocardiogram. This delay is called torsade de pointes, and it causes lightheadedness upon standing or even fainting, as blood pressure drops when the heart rhythm becomes abnormal. If the arrhythmia turns into the more erratic condition called ventricular fibrillation, it can be deadly. Some cases â¢of sudden cardiac arrest in people who apparently do not have heart disease are in fact due to long QT syndrome. This 'may have been the case with Roger's aunt, Amelia, his mother's sister, who died at age 34 of what was thought to be a heart attack, but, now Roger realizes, was more likely an arrhythmia. Still, with only one affected relative, Roger had never thought of his aunt's â¢early demise as a family history, especially since his mother is healthy. Roger reads that in people with some forms of long QT syndrome, fatal arrhythmia can be triggered by intense emotions or a sudden loud sound. The first recorded case of the condition was a little girl, who collapsed dead â¢when her teacher suddenly yelled at her. Her older brother had died in a similar circumstance. Suddenly, Roger remembers that his daughter Sheila faints very easily. She even passed out once at a rock concert because she got so excited. He'd never panicked over it because his mother fainted easily, too. A pattern was emerging. Long QT syndrome is caused by mutations in any of at least 10 genes that encode either proteins that form parts of ion channels (potassium, sodium, or calcium) or proteins that affect the functioning of these channels. Ion channels control the spread of nerve impulses and the resulting muscle contraction. The time for the heart's reeovery after a beat, called repolarization, extends the period when ions are trapped inside heart muscle cells because the channels are blocked, too slow to open, or too quick to close in people who are at elevated risk due to inheriting a mutation. People with long QT syndrome can experience arrhythmia if they take certain drugs that prolong the QT interval. These drugs include certain antibiotics, antidepressants, and diuretics ("water pills"). Roger reads about the different genes and drug combinations that cause long QT syndrome on Wikipedia, and then he scans www.genetests.org to find labs that test for all of them. Only then does he make an appointment with a cardiologist, and he arranges to have his blood and that of his daughter and mother sent to one of the labs. Two weeks later, he learns that they all have a dominant mutation in a gene called HERG (for "human ether-a-go-go") that causes long QT syndrome type 2 (LQT2). Even healthy family members could have inherited the mutation, because 15 percent of people with long QT syndrome do not have symptoms. The concern is their increased risk of developing symptoms in the futureâperhaps suddenly. | |||
Question 1 : Roger is upset that in the past doctors had not been more insistent that he follow up on the abnormal ECG pattern. When he mentions this to his primary care physician, she answers, "I didn't say anything because you are so healthy, and people who have cardiac arrest from long QT do so in young adulthood. You're too old to worry about it." But Roger should be worried, because
a. he looks younger than he is, so could still be at risk
b. the condition can be inherited, so others in the family could be affected.
c. he could die at any time.
d. he can no longer take antibiotics.
e. long QT syndrome can cause cholesterol to build up in his coronary arteries.
2. Individuals who should take genetic tests for long QT syndrome are
a. all the people in generation IV.
b. Eric, Joan and Peter, and then Dylan, Anika, Sean, Keri, and Anna if a parent has the mutation.
c. Juanita, Larry, Joan, Peter, and Ellie.
d. Abe, Sara, Craig, Philip, Edwin, and Yvonne.
e. Only those who are athletic.
3. The mode of inheritance of long QT syndrome in the Maxwell family is
a. X-Iinked recessive
.b. autosomal recessive.
c. autosomal dominant.
d. sex-limited.
e. X-Iinked dominant.
4. Some people who inherit the same mutation as Roger do not experience any symptoms. This means that the mutation is
a. variably expressive.
b. genetically heterogeneic.
c. polygenic.
d. incompletely penetrant.
e. dominant.
5). The fact that mutations in any of several genes can cause long QT syndrome means that the condition is
a. variably expressive.
b. genetically heterogeneic.
c. polygenic.
d. incompletely penetrant.
e.recessive.
6). The risk that Sean, Keri, or Anna has inherited the family's mutation for long QT syndrome is
a. 1
b. ¾
c. ¼
d. ¼
e. 1/8
7) Roger is relieved that he does not have- LQT7, which affects skeletal as well as cardiac muscle, causing short stature and scoliosis. He is also glad that he doesn't have LQT8, which causes many symptoms, or either of two types that also cause deafness. These other forms of the condition, with more than one symptom, exhibit
a. invariable expressivity.
b. complete penefrance.
c. genetic homogeneity.
d. pleiotropy.
e. phenocopy.
8) The reason that mutations in different genes all cause the same phenotype of extended QT interval on an ECG is that
a. the heart is an extremely complex organ.
b. the genes all encode proteins that affect ion channels essential for maintaining heartbeat.
c. the genes all encode the same protein.
d. the mutations all affect the genes in the same way.
e. the QT interval is highly variable, even within individuals at different times.
9). A phenotypic pattern in a family that could be due to inherited long QT syndrome is
a. sudden cardiac death in one or more young people and individuals who faint easily.
b. many individuals who eat a very fatty diet and are sedentary but do not develop heart disease.
c. many individuals with hypertension.
d. many individuals who suffer heart attacks after age 50.
e. a family with rnany athletes who have very low heart rates because of intense and frequent exercise.
Based on âMorgan: A case of Diabetesâ by Lisa Rubin and Clyde Freeman Herreid (National Center for Case Study Teaching in Science)
The Patient:
Morgan Water is a 27-year old Native American that lives on a reservation in Oklahoma. Nearly ¼ of Morganâs tribe has diabetes but she has no direct family history of diabetes, heart disease, or other serious conditions. She is however obese (BMI = 32) and leads a sedentary lifestyle. Morgan has been suffering from an increasing persistence of symptoms including unusual thirst, dizziness, blurred vision, and numbness in her right foot. The symptoms have been developing over several months but as she is planning her wedding she attributed them to nerves. She is finally persuaded to see her family doctor. Her non-fasting blood glucose level was elevated so the doctor has her return the next morning for a fasting blood sample so they could more accurately measure her blood glucose and insulin. Her blood results are below:
| Test | Morganâs values | Normal range | Pre-Diabetic range | Diabetic range |
| Plasma glucose, mg/dl | 260 | 70 -139 | 140 - 199 | ⥠200 |
| Fasting glucose, mg/dl | 140 | ⤠99 | 100 - 125 | ⥠126 |
| A1C, % | 7.6 | ~ 5 | 5.7 â 6.4 | ⥠6.5 |
| Fasting Insulin, mIU/ml | 34 | 2 - 10 | 10 - 20 | ⥠20 |
The recommendation of Morganâs doctor was to improve her exercise, good nutrition, and weight loss. He recommends meeting with a nutritionist to assist Morgan in her weight loss goals. When Morgan got home and told her family the diagnosis they however had LOTS of suggestions on how she can lose weight. Below is a description of the advice given to her by three family members.
Best friend Savannah:
âYou know how Iâve been losing weight? Well, Iâve been on the Atkinsâ Diet. I heard about it on TV. Itâs great! You get to eat steak, chicken wings, and all the good stuff. All you have to do is limit carbohydrate intake. You should definitely give it a try. This diet has been around for years and it has worked for lots of people, including me.â
*Note: Atkinâs Diet recommends: 10% carbohydrates, 55% fats, 35% protein
Brother Alan:
âI think the best thing for you to do is exercise and stop eating all of that pizza and candy and food filled with fat. Our people never used to eat that junk. I say eat meals that are nutritionally balanced and high in fiber and low in refined sugars and saturated fats. And run a lot. Stop sitting around the house.â
Grandfather:
âMorgan, it is true that it is best to live in harmony and balance â to eat a nutritionally balanced diet that includes carbohydrates, proteins, and âgoodâ fats to meet your bodyâs needs. That is good. But look to your heritage. Our people were never overweight before we started eating âcivilizedâ food. Look to our native diet. I think you should look to traditional herbal remedies for help. What Alan says is true. Exercise is good. But it is sometimes not enough. Our people have always looked to natural medicine for cures. They will lift your spirits and energize you. Then you will lose weight and you will be healthy again. I hear the herbs from the diet shop are safe and good. But you must take them like the medicine label says. It canât hurt to try them.â
*Note: these herbal supplements Morganâs grandfather is recommending contain the herb
ephedra (ephedrine).
Question 5:
Given Morganâs metabolic state, what is the primary fuel source for her cells currently?
A. Carbohydrates (glucose)
B. Fats
C. Proteins
D. It is a balance of all three
Question 6:
Metabolic ketoacidosis is a common problem with diabetics, which is caused by which of the following?
A. Excessive oxidation of fatty acids, leading to an accumulation of ketone bodies in the blood.
B. Excessive oxidation of glucose, leading to an accumulation of ketone bodies in the blood.
C. Excessive oxidation of proteins, leading to an accumulation of ammonia in the blood.
D. Hyperglycemia.
Question 7:
Which weight loss suggestion is designed to achieve some level of ketosis?
A. Atkins Diet
B. Exercise
C. High fiber diet
D. Herbal treatments
Question 8:
One major side effect of the herbal supplement can be hot flashes and increased perspiration due to increased thermogenesis, what is the likely cause of the heat production?
A. Increasing the activity of phosphfructokinase-1.
B. Increasing the activity of the pyruvate dehydrogenase complex.
C. Increasing the activity of citrate synthase.
D. Increasing the activity of uncoupling proteins.
Question 9:
Would substituting fiber and complex carbohydrates (larger % cellulose) for the simple sugars and starches (high sucrose and amylose/amylopectin) help Morgan lose weight, why?
A. Yes, because complex carbohydrates like cellulose are largely indigestible so they pass through
the digestive tract without being absorbed.
B. Yes, cellulose contains less glucose residues than amylose or amylopectin.
C. Yes, because the fructose in sucrose is much more responsible for weight gain than the glucose.
D. No, because cellulose, amylose, and amylopectin are all composed of glucose so it doesnât
matter.
Question 10:
Which weight loss suggestion will lead to an increased need for gluconeogenesis?
A. Atkins Diet
B. Exercise
C. High fiber diet
D. Herbal treatments