Reproduction — Set 3
Biology · प्रजनन · Questions 21–30 of 50
Which of the following is the common duct for both sperm and urine in males?
Correct Answer: B. Urethra
The urethra carries urine from the bladder and semen from the reproductive glands to the outside of the body. Sphincter muscles ensure that urine and semen do not pass at the same time. In females, the urethra is used only for urinary excretion.
A zygote undergoes rapid cell divisions to form a solid ball of cells called?
Correct Answer: D. Morula
The morula is an early-stage embryo consisting of 16 to 32 cells. It looks like a mulberry, which is where its name originates. It then develops into a hollow ball called a blastula or blastocyst.
Which structure stores sperm cells and allows them to mature?
Correct Answer: C. Epididymis
The epididymis is a coiled tube located on the back of each testis. Sperm cells gain motility and the ability to fertilize an egg while stored here. From here, they move into the vas deferens during ejaculation.
The fusion of male and female gametes to form a single cell is called?
Correct Answer: C. Fertilization
Fertilization restores the diploid number of chromosomes in the resulting zygote. In humans, this usually occurs internally within the female body. This process combines genetic material from both parents.
Which hormone is responsible for the production of milk in the mammary glands?
Correct Answer: A. Prolactin
Prolactin is secreted by the anterior pituitary gland to stimulate milk synthesis. While prolactin makes the milk, oxytocin is responsible for its release. Its levels increase significantly during pregnancy and breastfeeding.
What is the function of the scrotum in the male reproductive system?
Correct Answer: C. Maintaining temperature
The scrotum keeps the testes 2-3 degrees Celsius cooler than the internal body temperature. This lower temperature is essential for healthy sperm production. Muscles in the scrotum contract or relax to regulate this heat.
Which structure in the ovary develops from the ruptured follicle after ovulation?
Correct Answer: B. Corpus luteum
The corpus luteum secretes progesterone to maintain the uterine lining for pregnancy. If pregnancy does not occur, it degenerates into a scar called the corpus albicans. It is a temporary endocrine structure.
The scientific term for the act of giving birth is?
Correct Answer: D. Parturition
Parturition is the process of delivering the baby and the placenta from the uterus. It is triggered by complex hormonal signals from both the mother and the fetus. It involves three main stages: dilation, expulsion, and placental delivery.
Identical twins are formed from?
Correct Answer: B. One egg and one sperm
Identical or monozygotic twins result from a single fertilized egg that splits into two embryos. They share the same genetic makeup and are always of the same sex. Fraternal twins, on the other hand, result from two separate eggs and two separate sperm.
What is the total number of chromosomes in a human zygote?
Correct Answer: A. 46
A zygote is formed by the fusion of a sperm (23 chromosomes) and an egg (23 chromosomes). This results in a diploid cell with 46 chromosomes, which is the standard count for humans. These chromosomes contain the entire genetic blueprint for the new individual.