Nokea
If a cell has 92 chromosomes at the beginning of mitosis, determine the number of chromatids at
- A. 23 chromatids
- B. 92 chromatids
- C. 46 chromatids
- D. 184 chromatids
Correct Answer: C
Rationale: The correct answer is C: 46 chromatids. At the beginning of mitosis, each chromosome consists of two sister chromatids. Since the cell has 92 chromosomes, the total number of chromatids will be 92 chromosomes x 2 chromatids per chromosome = 184 chromatids. However, this number represents the total number of chromatids, not the number at the beginning of mitosis. At the beginning of mitosis, the sister chromatids are still attached, so we need to divide the total number of chromatids by 2 to get the number at the beginning of mitosis, which is 184 chromatids / 2 = 92 chromatids. Therefore, the correct answer is 46 chromatids, as each chromosome consists of two chromatids at the beginning of mitosis. Choices A, B, and D are incorrect as they do not consider the concept of sister chromatids in chromosomes during mitosis.
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A 22 year old male presents in your clinic, c/o pain in his testicle and penis. The pain began last night and has steadily become worse. He hurts when he urinates. He has not attempted intercourse since the pain began. He has tried Tylenol and Ibuprofen without improvement. Denies fever or night sweats. He has had 4 previous sexual partners and has had a new partner for the last month. She is using oral contraceptives and they do not use a condom. On exam, you see a young man lying on his side, mildly ill. His temp is 100.2. There are no visible lesions on the penis, or discharge from the meatus. The scrotum appears normal. Palpation of the testes reveals severe tenderness at the superior pole of the normal-sized left testicle. He also has tenderness when you palpate the structures superior to the testicle through the scrotal wall. The right testicle is unremarkable. An examining finger is placed through each inguinal ring without bulges noted with bearing down. Urine analysis shows WBCs and bacteria. What diagnosis of the male genitalia is most likely?
- A. Acute orchitis
- B. Acute epididymitis
- C. Torsion of the spermatic cord
- D. Prostatitis
Correct Answer: B
Rationale: The correct answer is B: Acute epididymitis. The patient's symptoms of pain in the testicle and penis, worsened pain with urination, and presence of WBCs and bacteria in the urine analysis are indicative of an infection. The severe tenderness at the superior pole of the left testicle and tenderness on palpation of structures superior to the testicle through the scrotal wall suggest involvement of the epididymis. The risk factors of multiple sexual partners and recent unprotected intercourse also support the diagnosis of epididymitis, which is commonly caused by sexually transmitted infections. Acute orchitis (choice A) typically presents with swelling and tenderness of the entire testicle, not just the epididymis. Torsion of the spermatic cord (choice C) presents with sudden onset severe testicular pain and may have a high-riding testicle. Prostatitis (choice D) presents with symptoms related to the prostate gland, such as pelvic
Which gland produces thick, clear mucus that cleanses the penile urethra of acidic urine?
- A. Testes
- B. Seminal vesicles
- C. Prostate
- D. Bulbourethral glands
Correct Answer: D
Rationale: The correct answer is D: Bulbourethral glands. These glands produce thick, clear mucus that cleanses the penile urethra of acidic urine before ejaculation. This mucus helps neutralize the acidity of urine, creating a more hospitable environment for sperm to travel through. The other choices are incorrect because:
A: Testes produce sperm, not mucus.
B: Seminal vesicles produce a fluid rich in fructose to nourish sperm.
C: Prostate produces a milky fluid that aids in sperm motility.
On inspection of the internal structure of the vagina, the nurse notes a rounded protrusion on the posterior wall of the vagina. How does the nurse document this finding?
- A. Rectocele
- B. Cystocele
- C. Bartholin cyst
- D. Nabothian cyst
Correct Answer: A
Rationale: The correct answer is A: Rectocele. A rectocele is a herniation of the anterior rectal wall into the posterior vaginal wall. The rounded protrusion on the posterior wall of the vagina indicates a rectocele. This finding is documented as a rectocele due to the specific anatomical location and nature of the protrusion.
Summary of other choices:
B: Cystocele - A cystocele is a herniation of the bladder into the anterior vaginal wall, not the posterior wall.
C: Bartholin cyst - Bartholin cyst is a fluid-filled swelling in the Bartholin gland near the vaginal opening, not on the posterior wall.
D: Nabothian cyst - Nabothian cysts occur on the cervix and are not related to protrusions on the posterior wall of the vagina.
The female reproductive system includes the following structures:
- A. ovary;
- B. Fallopian tubes;
- C. vagina;
- D. vulva;
Correct Answer: A
Rationale: The correct answer is A: ovary. The female reproductive system includes the ovaries, which are responsible for producing eggs and hormones like estrogen and progesterone. The Fallopian tubes are passageways for eggs to travel from the ovaries to the uterus, not a part of the system itself. The vagina is the birth canal and where sperm enters during intercourse, but it is not a reproductive organ. The vulva includes external genitalia like the labia and clitoris, but it is not a reproductive structure. Therefore, the ovary is the only structure directly involved in the reproductive process.
Infants of mothers who had adequate nutrition during pregnancy do not require iron supplements or a diet rich in iron until about 3 months of age. Why is this?
- A. Growth of the infant does not require iron until after the 3rd month
- B. The fetal liver stores enough iron to meet the infant’s needs until the third month
- C. Synthesis of new red blood cells begins after 3 months
- D. Muscle cells that develop before the 3rd month do not contain myoglobin
Correct Answer: B
Rationale: The correct answer is B: The fetal liver stores enough iron to meet the infant’s needs until the third month. During pregnancy, the fetus accumulates iron stores in the liver from the mother, which can sustain the infant's iron needs for the first few months of life. This stored iron is gradually utilized by the infant as the maternal iron supply diminishes post-birth.
Explanation of why the other choices are incorrect:
A: Growth of the infant does require iron even in the early months for various metabolic processes and functions.
C: Synthesis of new red blood cells starts shortly after birth, not necessarily after 3 months.
D: Myoglobin is not directly related to iron supplementation needs in infants and is unrelated to the timing of iron supplementation requirements.