When both of the alleles for a trait, such as hair color, are the same, the person is said to be _____ for that trait.
- A. monozygous
- B. dizygous
- C. homozygous
- D. hemizygous
Correct Answer: C
Rationale: A person is homozygous for a trait when they have two identical alleles for that trait. In this case, both alleles are the same, indicating a homozygous genotype. Choice A, 'monozygous,' is incorrect as it refers to identical twins originating from a single fertilized egg. Choice B, 'dizygous,' is also incorrect as it refers to fraternal twins or individuals that develop from two separate fertilized eggs. Choice D, 'hemizygous,' is incorrect because it describes a genetic condition where only one allele is present in a diploid organism, typically related to genes on the sex chromosomes.
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A client has experienced a fetal demise following a vaginal delivery at term. What should the nurse advise the client?
- A. "You can bathe and dress your baby if you'd like to."
- B. "If you don't hold the baby, it will make letting go much harder."
- C. "You should name the baby so he/she can have an identity."
- D. "I'm sure you will be able to have another baby when you're ready."
Correct Answer: A
Rationale: After a fetal demise, allowing the parents to bathe and dress their baby can offer them a sense of closure and help them in their grieving process. This act can provide a tangible way for the parents to bond with their baby and create lasting memories. Option B is incorrect because each individual may have different emotional needs and holding the baby may not be appropriate or helpful for everyone. Option C, while well-intentioned, may not be suitable for all parents as naming the baby could be emotionally challenging. Option D is insensitive as it overlooks the grieving process of losing a baby by suggesting a replacement.
Which of the following statements is true of mutations?
- A. Mutations can only occur by chance.
- B. Mutations produce sperm and ova cells.
- C. Mutations occur through radiation or other environmental influences.
- D. Mutations help adenine combine with guanine to form the single spiral structure of DNA.
Correct Answer: C
Rationale: The correct answer is C. Mutations can occur due to environmental influences such as radiation, chemicals, or other external factors, leading to changes in the DNA sequence. Choice A is incorrect because mutations can also occur due to errors in DNA replication, not solely by chance. Choice B is incorrect as mutations affect the DNA sequence itself, not the production of specific cells. Choice D is incorrect because mutations involve changes in the DNA sequence and do not specifically involve the formation of the DNA structure.
When assessing a woman in the first stage of labor, which clinical finding will alert the nurse that uterine contractions are effective?
- A. Dilation of the cervix.
- B. Descent of the fetus to -2 station.
- C. Rupture of the amniotic membranes.
- D. Increase in bloody show.
Correct Answer: A
Rationale: During the first stage of labor, effective uterine contractions lead to cervical dilation. Dilation of the cervix is a key indicator that uterine contractions are progressing labor. Descent of the fetus to -2 station (Choice B) is related to the fetal position in the pelvis and not a direct indicator of uterine contraction effectiveness. Rupture of the amniotic membranes (Choice C) signifies the rupture of the fluid-filled sac surrounding the fetus and does not directly reflect uterine contraction effectiveness. An increase in bloody show (Choice D) can be a sign of impending labor, but it is not a direct indicator of uterine contraction effectiveness.
A newborn nursery protocol includes a prescription for ophthalmic erythromycin 5% ointment to both eyes upon a newborn's admission. What action should the nurse take to ensure adequate installation of the ointment?
- A. Instill a thin ribbon into each lower conjunctival sac
- B. Occlude the inner canthus after retracting the eyelids
- C. Mummy wrap the infant before instilling the ointment
- D. Stabilize the instilling hand on the neonate's head
Correct Answer: A
Rationale: To ensure adequate installation of the ophthalmic erythromycin 5% ointment in a newborn, the nurse should instill a thin ribbon into each lower conjunctival sac. This method helps to ensure proper distribution and effectiveness of the medication to prevent neonatal conjunctivitis. Choices B, C, and D are incorrect. Occluding the inner canthus after retracting the eyelids, mummy wrapping the infant, or stabilizing the instilling hand on the neonate's head are not appropriate actions for ensuring the proper installation of the ointment.
Which of the following statements about Rh incompatibility is true?
- A. Rh incompatibility occurs most commonly during a woman's first pregnancy.
- B. Rh incompatibility is an untreatable condition that leaves a woman infertile for the rest of her life.
- C. Rh incompatibility is an abnormality that is transmitted from generation to generation and carried by a sex chromosome.
- D. Rh incompatibility occurs due to antibodies transmitted to a fetus during subsequent deliveries causing brain damage or death.
Correct Answer: D
Rationale: Rh incompatibility occurs when the mother's antibodies attack the fetus's red blood cells, leading to serious complications, usually in subsequent pregnancies. Choice A is incorrect because Rh incompatibility often occurs in subsequent pregnancies, not necessarily the first one. Choice B is incorrect as Rh incompatibility does not render a woman infertile but can lead to complications during pregnancies. Choice C is incorrect as Rh incompatibility is not carried by a sex chromosome but involves the Rh factor on red blood cells.