Nokea
Each statement is true of proteins, except one. Which is the exception?
- A. Proteins are composed of building blocks called amino acids
- B. The classification of the 20 common amino acids is based on the properties of their side chains
- C. The general structure of an amino acid varies considerably
- D. Amino acids polymerize to form long chains called polypeptides
Correct Answer: B
Rationale: The correct answer is B. The classification of the 20 common amino acids is not based on the properties of their side chains, but rather on the structure of their amino and carboxyl groups. These groups are consistent among all amino acids, while the side chains, also known as R groups, are what vary and give each amino acid its unique properties. Choice A is correct because proteins are indeed composed of amino acids. Choice C is incorrect because while the side chains of amino acids can vary, the general structure of an amino acid - a central carbon atom bonded to an amino group, a carboxyl group, a hydrogen atom, and a side chain - is consistent. Choice D is correct because amino acids do polymerize to form long chains called polypeptides, which can then fold into complex shapes to form proteins.
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What goal should an overweight woman include in her lifestyle for a healthy pregnancy?
- A. Aim to lose 11 to 20 pounds during pregnancy
- B. Increase protein intake to 35% of total calories
- C. Delay weight loss until after pregnancy
- D. Increase daily energy intake by 550 calories
Correct Answer: C
Rationale: The healthiest approach for an overweight pregnant woman is to delay weight loss until after pregnancy. During pregnancy, the body needs sufficient nutrition and energy to support the growth and development of the baby. Attempting to lose weight during pregnancy, especially significant amounts, may compromise the health of both the mother and the baby. Increasing protein intake to 35% of total calories or energy intake by 550 calories per day without professional guidance may lead to an unbalanced diet, which is not optimal for pregnancy. The focus should be on maintaining a balanced, nutrient-rich diet and appropriate weight gain during pregnancy.
What should Mrs. Smith do to increase her HDL levels, as advised by the nurse?
- A. Monitor her blood glucose levels
- B. Quit smoking
- C. Control her blood pressure
- D. Take fish oil supplements
Correct Answer: B
Rationale: The correct answer is 'Quit smoking.' Smoking has been shown to lower HDL (High-Density Lipoprotein) levels, and quitting can help to improve these levels. HDL is often referred to as 'good cholesterol' because it helps to remove other forms of cholesterol from the bloodstream, reducing the risk of heart disease. While monitoring blood glucose levels, controlling blood pressure, and taking fish oil supplements can contribute to overall health and wellbeing, they do not directly increase HDL levels in the same way that quitting smoking does. Therefore, quitting smoking is the most effective way for Mrs. Smith to increase her HDL levels as advised by the nurse.
Which gluten-free food choice would be most appropriate for a patient with celiac disease?
- A. Scalloped potatoes
- B. Oatmeal
- C. Eggs
- D. Tortillas
Correct Answer: C
Rationale: Eggs are a safe food choice for individuals with celiac disease as they are naturally gluten-free. Scalloped potatoes often contain flour in the sauce, which might contain gluten. Oatmeal can be a subject of debate due to possible cross-contamination during processing, so it might not be safe unless labeled gluten-free. Tortillas are typically made from wheat flour containing gluten, but gluten-free versions are available. However, eggs are universally gluten-free, making them the best choice for individuals with celiac disease.
In a patient with liver cirrhosis, weight gain due to fluid retention can mask the symptoms of what condition?
- A. Liver failure
- B. Gallbladder disease
- C. Heart failure
- D. Protein-Energy Malnutrition (PEM)
Correct Answer: D
Rationale: In a patient with liver cirrhosis, weight gain due to fluid retention can mask Protein-Energy Malnutrition (PEM) symptoms. This can lead to an increase in weight, making it challenging to identify weight loss or muscle wasting associated with PEM. Therefore, option D is correct. Options A, B, and C are incorrect because fluid retention and weight gain related to liver cirrhosis do not necessarily hide the symptoms of liver failure, gallbladder disease, or heart failure.
Which of the following conditions is not caused by energy drinks?
- A. Nervousness
- B. Bradycardia
- C. Seizures
- D. Dental caries
Correct Answer: B
Rationale: Energy drinks are known for causing a variety of health issues, including nervousness, seizures, and an increased risk of dental caries due to their high sugar content. However, they do not cause bradycardia, which is a slow heart rate. Instead, energy drinks are associated with causing an increased or rapid heart rate, known as tachycardia. Therefore, out of the listed options, bradycardia is the condition not caused by energy drinks.