Nokea
Dizygotic (DZ) twins share _________ percent of their genes.
- A. 100
- B. 75
- C. 50
- D. 25
Correct Answer: C
Rationale: Dizygotic (DZ) twins share approximately 50% of their genes. This is because dizygotic twins, also known as fraternal twins, originate from two separate fertilized eggs and share similar genetic similarity to regular siblings. Choice A (100%) is incorrect because if twins shared 100% of their genes, they would be identical twins (monozygotic). Choice B (75%) is incorrect as it is not the typical genetic similarity seen in dizygotic twins. Choice D (25%) is incorrect as it represents a significantly lower genetic similarity than what is observed in dizygotic twins.
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A woman with gestational diabetes has had little or no experience reading and interpreting glucose levels. The client shows the nurse her readings for the past few days. Which reading signals the nurse that the client may require an adjustment of insulin or carbohydrates?
- A. 75 mg/dl before lunch. This is low; better eat now.
- B. 115 mg/dl 1 hour after lunch. This is a little high; maybe eat a little less next time.
- C. 115 mg/dl 2 hours after lunch. This is too high; it is time for insulin.
- D. 50 mg/dl just after waking up from a nap. This is too low; maybe eat a snack before going to sleep.
Correct Answer: D
Rationale: 50 mg/dl after waking from a nap is too low. During hours of sleep, glucose levels should not be less than 60 mg/dl. Snacks before sleeping can be helpful. The premeal acceptable range is 60 to 99 mg/dl. The readings 1 hour after a meal should be less than 129 mg/dl. Two hours after eating, the readings should be less than 120 mg/dl.
A new parent is receiving discharge teaching about car seat safety from a nurse. Which statement by the parent indicates an understanding of the teaching?
- A. "I should position my baby's car seat at a 45-degree angle in the car."
- B. "I should place the car seat rear-facing until my baby is 12 months old."
- C. "I should place the harness snugly in a slot above my baby's shoulders."
- D. "I should position the retainer clip at the top of my baby's abdomen."
Correct Answer: A
Rationale: The correct answer is A. Positioning the car seat at a 45-degree angle is crucial to prevent the baby's head from falling forward, which can obstruct the airway. Choice B is incorrect because the recommendation is to keep the car seat rear-facing until the baby reaches the height or weight limit set by the car seat manufacturer, typically beyond 12 months. Choice C is incorrect as the harness should be snugly placed at or below the baby's shoulders, not above. Choice D is incorrect as the retainer clip should be positioned at armpit level to secure the harness straps properly.
Most victims of _____ die of respiratory infections in their 20s.
- A. Tay-Sachs disease
- B. cystic fibrosis
- C. Turner syndrome
- D. Klinefelter syndrome
Correct Answer: B
Rationale: Individuals with cystic fibrosis have a genetic disorder that causes mucus to be thick and sticky, leading to blockages in the lungs and digestive system. This mucus buildup makes them more susceptible to severe respiratory infections, which can ultimately result in premature death in their 20s. Tay-Sachs disease (Choice A) is a genetic disorder that affects the nervous system, not typically causing respiratory infections. Turner syndrome (Choice C) and Klinefelter syndrome (Choice D) are chromosomal disorders that do not directly lead to the respiratory issues observed in cystic fibrosis.
Which of the following pairs share 100% of their genes?
- A. Biovular twins
- B. Fraternal twins
- C. Dizygotic (DZ) twins
- D. Monozygotic (MZ) twins
Correct Answer: D
Rationale: The correct answer is Monozygotic (MZ) twins. Monozygotic twins, also known as identical twins, share 100% of their genes because they originate from the same fertilized egg that splits into two. Fraternal twins (choice B), also known as dizygotic (DZ) twins (choice C), result from two separate fertilized eggs and share approximately 50% of their genes. Biovular twins (choice A) is not a term used in genetics and does not describe a type of twinning.
Chromosomes contain thousands of segments called:
- A. nuclei.
- B. nodes.
- C. capillaries.
- D. genes.
Correct Answer: D
Rationale: Chromosomes are structures composed of DNA and genes. Genes are the functional segments within chromosomes that encode specific traits and characteristics. The other choices ('nuclei,' 'nodes,' 'capillaries') do not accurately describe the segments found within chromosomes and are unrelated to their structure or function.