1.
Human Spermatogonia:
Correct Answer
C. Are germ cells that reside within the Seminiferous Tubules
Explanation
Human spermatogonia are germ cells that reside within the seminiferous tubules. Germ cells are the cells that give rise to gametes (sperm or eggs), and spermatogonia specifically are the cells in the testes that undergo mitosis to produce primary spermatocytes. The seminiferous tubules are the structures in the testes where sperm production takes place. Therefore, the correct answer is that human spermatogonia are germ cells that reside within the seminiferous tubules.
2.
Which of the following statements best characterizes asexual reproduction?
Correct Answer
B. It allows an animal to produce many offspring quickly
Explanation
Asexual reproduction allows an animal to produce many offspring quickly because it does not require the time and energy to find a mate and produce gametes. This type of reproduction involves the production of offspring from a single parent, without the involvement of gametes or the fusion of genetic material. As a result, asexual reproduction can lead to the rapid multiplication of individuals, allowing for the quick expansion of a population and the exploitation of available resources.
3.
Athletes who take synthetic steroids can become sterile due to lack of sperm production. This is because of negative feedback on which of the following?
Correct Answer
B. The Testes
Explanation
The testes are responsible for sperm production in males. Synthetic steroids can disrupt the normal functioning of the testes, leading to a decrease in sperm production. This is because synthetic steroids can suppress the production of luteinizing hormone (LH) and follicle-stimulating hormone (FSH), which are necessary for the production of sperm. Without sufficient LH and FSH, the testes cannot produce an adequate amount of sperm, resulting in sterility.
4.
The cells in the ovary that gives rise to the mature egg cells are the:
Correct Answer
E. Oocytes
Explanation
Oocytes are the cells in the ovary that give rise to mature egg cells. They undergo a process called oogenesis, where they develop and mature into eggs. This process involves several stages, including the growth and maturation of the oocyte within a follicle. Once mature, the oocyte is released from the ovary during ovulation and can be fertilized by sperm to form an embryo. Therefore, oocytes are the correct answer as they are directly involved in the production of mature egg cells.
5.
Often a woman may first suspect she is pregnant when she misses a period or menstrual cycle. Why is it important for the menstural cycle to be blocked during pregnancy?
Correct Answer
D. To prevent the Blastocyst from being lost
Explanation
During pregnancy, the blastocyst, which is the early stage of embryo development, implants itself into the uterus lining. If the menstrual cycle were to continue during pregnancy, it could potentially cause the blastocyst to be shed and lost, resulting in a miscarriage. Therefore, blocking the menstrual cycle is important to ensure the blastocyst remains implanted and the pregnancy can progress successfully.
6.
Athletes who take synthetic steroids can become sterile due to lack of sperm production. This is because of negative feedback on which of the following?
Correct Answer
A. A decrease in FSH and LH production
Explanation
Taking synthetic steroids can disrupt the normal hormonal balance in the body. Synthetic steroids can mimic the effects of natural testosterone and suppress the production of follicle-stimulating hormone (FSH) and luteinizing hormone (LH) in the body. FSH and LH are essential for the production of sperm in males. Therefore, a decrease in FSH and LH production due to negative feedback is the likely cause of sterility in athletes who take synthetic steroids.
7.
Which of the following statements about the reproductive system of human females is true?
Correct Answer
B. The Corpus Luteum secretes Progesterone, which helps maintain the uterine lining during pregnancy
Explanation
The Corpus Luteum secretes Progesterone, which helps maintain the uterine lining during pregnancy. Progesterone is a hormone that is produced by the Corpus Luteum, which is formed after the release of an egg from the ovary. This hormone plays a crucial role in preparing and maintaining the uterus for implantation of a fertilized egg. It helps to thicken the uterine lining, making it suitable for the implantation and development of the embryo. If pregnancy occurs, the Corpus Luteum continues to produce progesterone to support the pregnancy. If pregnancy does not occur, the Corpus Luteum degenerates, leading to a decrease in progesterone levels and the shedding of the uterine lining during menstruation.
8.
The human egg is swept through the oviduct toward the Uterus by:
Correct Answer
E. The beating of the cilia in the oviduct
Explanation
The cilia in the oviduct are responsible for sweeping the human egg towards the uterus. Cilia are tiny hair-like structures that line the oviduct and create a wave-like motion, propelling the egg forward. This movement helps to transport the egg from the ovary, where it is released, to the uterus, where it can potentially be fertilized. The beating of the cilia is essential for the successful movement of the egg through the reproductive system.
9.
Fertilization in the female reproductive tract most often takes place in the :
Correct Answer
B. Upper 1/3 of the oviduct
Explanation
The upper 1/3 of the oviduct is the most common site for fertilization in the female reproductive tract. This is because after ovulation, the egg is released from the ovary and travels through the oviduct. The oviduct provides a suitable environment for fertilization to occur, as it is lined with cilia that help move the egg and sperm towards each other. Additionally, the oviduct has secretions that nourish the egg and provide the necessary conditions for fertilization to take place. Once fertilization occurs, the fertilized egg will continue its journey towards the uterus for implantation.
10.
Birth control pills contain and combination of Estrogen and Progesterone. What effect would this have on the Hypothalamus?
Correct Answer
D. It would secrete less GonadotropHin Releasing Hormone
Explanation
The combination of estrogen and progesterone in birth control pills would have the effect of reducing the secretion of Gonadotrophin Releasing Hormone by the hypothalamus. This is because estrogen and progesterone act as negative feedback signals to the hypothalamus, inhibiting the release of Gonadotrophin Releasing Hormone. As a result, the secretion of follicle-stimulating hormone (FSH) and luteinizing hormone (LH) by the pituitary gland would also be reduced.
11.
Human testes are positioned in an external sac rather than in the abdominal cavity:
Correct Answer
D. So the testes can be kept cooler than the body's interior
Explanation
The testes are positioned in an external sac, called the scrotum, to keep them cooler than the body's interior. Sperm production requires a lower temperature than the rest of the body, and the scrotum's location outside the abdominal cavity helps regulate and maintain a cooler temperature for optimal sperm production. This is important for fertility and the overall reproductive health of males.
12.
Men who take very long, hot bathes are likely to:
Correct Answer
D. Produce fewer sperm
Explanation
Taking long, hot baths can increase the temperature of the testicles, which can negatively affect sperm production. The testicles need to be slightly cooler than the body's temperature for optimal sperm production. Therefore, men who take very long, hot baths are likely to produce fewer sperm.
13.
After being produced in the testes, sperm mature further in a structure called the:
Correct Answer
B. Epididymis
Explanation
After being produced in the testes, sperm mature further in a structure called the epididymis. The epididymis is a long, coiled tube located on the back of each testicle. It serves as a storage and maturation site for sperm. Here, the sperm gain the ability to swim and become motile, as well as acquire the ability to fertilize an egg. The epididymis also helps in the transportation of sperm from the testes to the vas deferens during ejaculation.
14.
Which of the following produce a thick fluid containing fructose, which is used for energy by sperm?
Correct Answer
C. Seminal Vesicles
Explanation
The seminal vesicles produce a thick fluid containing fructose, which is used for energy by sperm. This fluid, along with sperm from the testes and fluids from other glands, makes up semen. The fructose in the seminal fluid provides energy for the sperm to swim and survive in the female reproductive tract.
15.
Which of the following statements regarding Spermatogenesis and Oogenesis is true?
Correct Answer
B. Meiosis in Oogenesis produces on mature egg from one primary Oocyte
Explanation
Meiosis in Oogenesis produces one mature egg from one primary Oocyte. During oogenesis, the primary oocyte undergoes meiosis I to produce one secondary oocyte and one polar body. The secondary oocyte then undergoes meiosis II to produce one mature egg and another polar body. This process results in the production of only one mature egg from one primary oocyte.
16.
Which of the following statements regarding Spermatogenesis and Oogenesis is true?
Correct Answer
C. Men, but not women, can produce gametes throughout their lives
17.
Menstuation:
Correct Answer
E. Coincides with the beginning of the pre-ovulatory pHase of the ovarian cycle
Explanation
Menstruation coincides with the beginning of the pre-ovulatory phase of the ovarian cycle. This is because during this phase, the levels of estrogen and progesterone decrease, causing the lining of the uterus to shed. This shedding results in menstruation. The LH surge, HCG, and post-ovulatory phase of the ovarian cycle are not directly associated with menstruation.
18.
In human females, the ovarian cycle begins when:
Correct Answer
C. The Hypothalamus stimulates the Anterior Pituitary to increase its output of FSH and LH
Explanation
The correct answer is that the hypothalamus stimulates the anterior pituitary to increase its output of FSH and LH. This is because the ovarian cycle is regulated by a feedback loop involving the hypothalamus, pituitary gland, and ovaries. The hypothalamus releases gonadotropin-releasing hormone (GnRH), which stimulates the anterior pituitary to release follicle-stimulating hormone (FSH) and luteinizing hormone (LH). These hormones then stimulate the ovaries to produce and release estrogen and progesterone, which regulate the different phases of the ovarian cycle. Therefore, the hypothalamus stimulating the anterior pituitary to increase its output of FSH and LH is the correct answer.
19.
Which of the following hormones stimulates the growth of an ovarain follicle?
Correct Answer
B. FSH
Explanation
FSH (follicle-stimulating hormone) stimulates the growth and development of ovarian follicles in the ovaries. It is released by the pituitary gland in response to signals from the hypothalamus. FSH plays a crucial role in the menstrual cycle, as it stimulates the growth of multiple follicles, which contain the eggs. As the follicles grow, they produce estrogen, which further stimulates the development of the uterine lining. Eventually, one follicle becomes dominant and releases a mature egg during ovulation. FSH is therefore responsible for initiating the process of follicle development and egg maturation in the ovaries.
20.
A decrease in _ is followed by the gradual degradation of the Corpus Luteum
Correct Answer
A. LH
Explanation
LH, or luteinizing hormone, is responsible for triggering ovulation and the formation of the Corpus Luteum. The Corpus Luteum produces progesterone, which is necessary for maintaining a pregnancy. Therefore, a decrease in LH levels would lead to the gradual degradation of the Corpus Luteum, as it would not receive the necessary stimulation to continue producing progesterone.
21.
Often a woman may first suspect she is pregnant when she misses a period or menstrural cycle. What causes a pregnant woman to miss a period?
Correct Answer
A. Chorionic GonadotropHin causes the Corpus Luteum to produce Progesterone
Explanation
During pregnancy, the chorionic gonadotropin hormone (hCG) is produced by the placenta. This hormone stimulates the corpus luteum, which is the structure formed in the ovary after ovulation, to continue producing progesterone. Progesterone is essential for maintaining the thickened uterine lining, which is necessary for the implantation and development of the fertilized egg. Therefore, if a woman is pregnant, the presence of hCG will cause the corpus luteum to produce progesterone, leading to the absence of menstruation or a missed period.
22.
The function of a sperm cell's Acrosome is to:
Correct Answer
C. Carry enzymes that are released to form a hole in the egg's jelly coat when the sperm encounters an egg
Explanation
The Acrosome of a sperm cell contains enzymes that are released to form a hole in the egg's jelly coat when the sperm encounters an egg. This allows the sperm to penetrate the egg and fertilize it. The other options listed do not accurately describe the function of the Acrosome.
23.
Which of the following events occurs first during embryonic development?
Correct Answer
C. Cleavage
Explanation
Cleavage is the first event that occurs during embryonic development. It is the process of rapid cell division that takes place after fertilization, resulting in the formation of a multicellular embryo called a blastocyst. Cleavage is essential for the growth and development of the embryo and allows for the formation of specialized cells and tissues. Gastrulation, neurulation, implantation, and aggregation occur at later stages of embryonic development.
24.
In humans, the transparent sac that contains fluid that cushions the embryo and maintains and constant temperature and pressure is the:
Correct Answer
A. Amnion
Explanation
The amnion is the correct answer because it is the transparent sac that contains fluid, known as amniotic fluid, which cushions the embryo. The amnion also helps maintain a constant temperature and pressure for the developing embryo.
25.
Another term for gestation is:
Correct Answer
E. Pregnancy
Explanation
Gestation refers to the period of time during which a fetus develops inside the womb of a pregnant woman. It encompasses the entire process of pregnancy, from the fertilization of the egg to the birth of the baby. Therefore, pregnancy is another term for gestation.