According to a study conducted in 2013 by Fellman, what affects the chances of having twins?
- A. Increase when a woman conceives at a younger age.
- B. Increase with parental age.
- C. Decrease with the frequency of intercourse before conception.
- D. Decrease with the use of fertility drugs.
Correct Answer: B
Rationale: The correct answer is B. According to the study by Fellman in 2013, the chances of having twins actually increase with parental age. Choice A is incorrect as the study does not specify a younger age for conceiving to increase the chances of twins. Choice C is incorrect as the frequency of intercourse before conception is not a highlighted factor in the study. Choice D is also incorrect as the study does not discuss the impact of fertility drugs on the likelihood of having twins.
You may also like to solve these questions
Before meiosis, a sperm cell:
- A. contains 46 chromosomes.
- B. contains two X chromosomes.
- C. is significantly larger than an egg cell.
- D. contains both an X and a Y chromosome.
Correct Answer: A
Rationale: Before meiosis, a sperm cell contains 46 chromosomes. This is because sperm cells, like other somatic cells, have a diploid number of chromosomes. During meiosis, the number of chromosomes is halved to 23 to combine with an egg cell during fertilization. Choice B is incorrect because a sperm cell carries either an X or a Y chromosome, not both (Choice D). Choice C is incorrect as sperm cells are generally smaller than egg cells, which is an adaptation that aids in motility and penetration of the egg during fertilization.
A nurse is planning to teach a group of clients who are breastfeeding after returning to work. Which of the following instructions should the nurse include in the teaching?
- A. "Thawed breast milk can be refrigerated for up to 24 hours."
- B. "Breast milk can be stored in a deep freezer for 12 months."
- C. "Breast milk can be stored at room temperature for up to 4 hours."
- D. "Thawed breast milk that is unused cannot be refrozen."
Correct Answer: B
Rationale: The correct answer is B: "Breast milk can be stored in a deep freezer for 12 months." This instruction is important for mothers returning to work to ensure a long-term storage option for breast milk. Choice A is incorrect because thawed breast milk should be used within 24 hours if stored in the refrigerator. Choice C is incorrect as breast milk can be kept at room temperature for only up to 4 hours. Choice D is incorrect as thawed breast milk that is unused should not be refrozen due to safety concerns.
Which of the following statements is true of sickle-cell anemia?
- A. It is typically managed with treatments such as pain relief medications.
- B. It is caused by a mutation in the beta-globin gene.
- C. It leads to the obstruction of small blood vessels and decreased oxygen delivery.
- D. It is more prevalent in individuals of African, Mediterranean, Middle Eastern, and Indian descent.
Correct Answer: C
Rationale: The correct answer is C. Sickle-cell anemia results from a mutation in the beta-globin gene, causing red blood cells to become sickle-shaped. These misshapen cells can obstruct small blood vessels, leading to reduced oxygen delivery to tissues. Choices A, B, and D are incorrect because sickle-cell anemia is typically managed with treatments such as pain relief medications, hydration, and in severe cases, blood transfusions. It is caused by a specific mutation in the beta-globin gene, not by the inability to metabolize phenylalanine. Additionally, sickle-cell anemia is more prevalent in individuals of African, Mediterranean, Middle Eastern, and Indian descent, not exclusive to any specific gender.
A client at 20 weeks of gestation has trichomoniasis. Which of the following findings should the nurse expect?
- A. Thick, White Vaginal Discharge
- B. Urinary Frequency
- C. Vulvar Lesions
- D. Malodorous Discharge
Correct Answer: D
Rationale: Malodorous discharge is a common symptom of trichomoniasis caused by the Trichomonas vaginalis parasite. It is typically described as frothy, greenish-yellow, and malodorous. Choices A, B, and C are incorrect findings associated with other conditions. Thick, white vaginal discharge is more characteristic of a yeast infection; urinary frequency may be seen in urinary tract infections; and vulvar lesions are commonly seen in herpes simplex virus infections.
Which of the following pairs of bases is present in the rungs of the ladder-like structure of deoxyribonucleic acid (DNA)?
- A. Cytosine with guanine.
- B. Rhodamine with biotin.
- C. Diaminopurine with ribozyme.
- D. Serine with tyrosine.
Correct Answer: A
Rationale: The correct answer is A: Cytosine with guanine. In the DNA double helix, cytosine always pairs with guanine forming a base pair, and adenine pairs with thymine. These complementary base pairs form the rungs of the ladder-like structure of DNA. Choice B, Rhodamine with biotin, is incorrect as they are not base pairs found in DNA. Choice D, Serine with tyrosine, is incorrect as they are amino acids, not DNA bases. Choice C, Diaminopurine with ribozyme, is also incorrect as ribozyme is an enzyme, not a base, and diaminopurine is not one of the standard bases found in DNA.