If an individual receives a recessive gene for eye color from both parents, the:
- A. gender of the child will not determine the expression of that trait.
- B. recessive trait will be expressed in the child.
- C. recessive trait will be expressed in all the offspring.
- D. recessive trait will be suppressed, and the dominant trait will not be expressed.
Correct Answer: B
Rationale: When an individual inherits a recessive gene for eye color from both parents, the recessive trait will be expressed in the child. This is because having two copies of the recessive gene overrides the presence of any dominant gene. Choice A is incorrect because the expression of the trait is determined by the genetic makeup, not the gender of the child. Choice C is incorrect as the expression of the recessive trait is certain when both parents pass on the recessive gene, but it does not mean that all offspring will express the trait. Choice D is incorrect because if both parents provide a recessive gene, the dominant trait will not be expressed in the child, but it does not mean it will be suppressed; rather, the recessive trait will be expressed.
You may also like to solve these questions
Which field of biology studies heredity?
- A. Etiology.
- B. Ecology.
- C. Genetics.
- D. Eugenics.
Correct Answer: C
Rationale: Genetics is the branch of biology that focuses on the study of heredity and variation in organisms. Etiology (choice A) deals with the causes of diseases, not heredity. Ecology (choice B) is concerned with the relationships between organisms and their environment, not specifically heredity. Eugenics (choice D) is a controversial field that involves improving the genetic quality of the human population through selective breeding, which is different from the study of heredity itself.
Is color blindness a sex-linked abnormality?
- A. TRUE
- B. FALSE
- C. Sometimes
- D. Always
Correct Answer: A
Rationale: The correct answer is A: TRUE. Color blindness is indeed a sex-linked abnormality as it is often associated with genes on the X chromosome. Since males have only one X chromosome, they are more likely to inherit color blindness if the gene is present. This makes color blindness more common in males. Choice B (FALSE) is incorrect because color blindness is linked to the X chromosome. Choices C (Sometimes) and D (Always) are incorrect as color blindness is consistently tied to the X chromosome.
According to a study in 2013 by van Gameren-Oosterom, individuals with Down syndrome:
- A. are unlikely to die from cardiovascular problems by middle age.
- B. have no specific characteristic features.
- C. show deficits in cognitive development.
- D. are likely to have only 46 chromosomes.
Correct Answer: C
Rationale: The correct answer is C. According to a study in 2013 by van Gameren-Oosterom, individuals with Down syndrome often exhibit deficits in cognitive development. This is a common characteristic of Down syndrome, along with other health challenges. Choice A is incorrect because individuals with Down syndrome are at a higher risk of cardiovascular problems, contrary to being unlikely to die from them. Choice B is incorrect as Down syndrome is associated with specific characteristic features such as distinctive facial characteristics, making the statement that they have no specific features incorrect. Choice D is incorrect as individuals with Down syndrome have an extra copy of chromosome 21, resulting in a total of 47 chromosomes, not 46.
What information should the nurse include when teaching a client at 41 weeks of gestation about a non-stress test?
- A. This test will confirm fetal lung maturity.
- B. This test will determine the adequacy of placental perfusion.
- C. This test will detect fetal infection.
- D. This test will predict maternal readiness for labor.
Correct Answer: B
Rationale: The correct answer is B: 'This test will determine the adequacy of placental perfusion.' The non-stress test is used to assess fetal well-being by monitoring the fetal heart rate in response to its own movements. It helps determine if the fetus is receiving enough oxygen and nutrients through placental perfusion. Choice A is incorrect because confirming fetal lung maturity is typically determined through tests like amniocentesis, not the non-stress test. Choice C is incorrect because detecting fetal infection is not the primary purpose of a non-stress test. Choice D is incorrect because predicting maternal readiness for labor is not the purpose of the non-stress test; it focuses on fetal well-being.
The healthcare provider prescribes 10 units per liter of oxytocin via IV drip to augment a client's labor because she is experiencing a prolonged active phase. Which finding would cause the nurse to immediately discontinue the oxytocin?
- A. Contraction duration of 100 seconds.
- B. Four contractions in 10 minutes.
- C. Uterus is soft.
- D. Early deceleration of fetal heart rate.
Correct Answer: A
Rationale: A contraction duration of 100 seconds is too long and can indicate uterine hyperstimulation, which can lead to fetal distress and other complications. This prolonged contraction duration suggests that the uterus is not relaxing adequately between contractions, potentially compromising fetal oxygenation. Choice B, 'Four contractions in 10 minutes,' is a sign of tachysystole, which is concerning but not as immediately critical as the prolonged contraction duration. Choice C, 'Uterus is soft,' is not a reason to discontinue oxytocin; in fact, it is a normal finding. Choice D, 'Early deceleration of fetal heart rate,' while indicating fetal distress, is not a direct result of the oxytocin and may require intervention but not immediate discontinuation of the medication.