Female Reproductive System And Menstruation Cycle! Trivia Quiz

During the proliferative phase of the menstrual cycle, the endometrium (lining of the uterus) thickens and prepares for implantation of a fertilized egg. Estrogen is the hormone that influences this phase by stimulating the growth and development of the endometrium. It promotes cell division and increases blood flow to the uterus, creating a favorable environment for implantation. Estrogen also plays a role in the maturation of ovarian follicles, preparing them for ovulation.

After the secondary oocyte is fertilized, the syncytiotrophoblast cells in the developing placenta produce human chorionic gonadotropin (hCG). This hormone maintains the viability of the corpus luteum, preventing it from degenerating. The corpus luteum is responsible for producing progesterone, which is essential for maintaining the uterine lining and supporting early pregnancy. If the corpus luteum degenerates, progesterone levels drop, leading to menstruation. Therefore, the production of hCG by the syncytiotrophoblast cells ensures the survival of the corpus luteum and the continuation of pregnancy.

During the menstrual cycle, estrogen stimulates the repair of the endometrium during the proliferative phase. This is because estrogen is responsible for the thickening of the endometrium, preparing it for potential implantation of a fertilized egg. Estrogen promotes the growth and development of the endometrial cells, increasing the blood supply to the uterus and causing the lining to become thicker. This prepares the uterus for potential pregnancy and creates a suitable environment for the fertilized egg to implant and develop.

The correct answer states that at the time of ovulation, the released egg is a secondary oocyte arrested at metaphase II of meiosis II. This means that the egg has completed the first meiotic division and is now in the second meiotic division, but it is arrested at the metaphase stage. This is the stage at which the egg is released from the ovary and is ready to be fertilized by a sperm.

At the time of birth in the XX individual, the gonad will contain primordial follicles with primary oocytes of prophase I. This is because the development of oocytes begins during fetal life, and by the time of birth, the oocytes have reached the prophase I stage of meiosis. The primordial follicles, which consist of an oocyte surrounded by a single layer of flat cells, are the earliest stage of follicle development in the ovary. These follicles will eventually mature and develop into graafian follicles, which contain secondary oocytes at metaphase II, but this occurs later in life during the menstrual cycle.

Primary oocytes are indeed arrested in the diplotene stage of prophase 1 before birth. This is a crucial stage in meiosis where the homologous chromosomes pair up and undergo recombination. The primary oocytes remain arrested in this stage until puberty when they resume meiosis and complete the process to become mature eggs.

The correct answer is a primary oocyte surrounded by a single layer of cuboidal or columnar follicular cells. This statement best describes the unilaminar primary follicle, which is an early stage in the development of an ovarian follicle. The primary oocyte is the immature egg cell, and it is surrounded by a single layer of cuboidal or columnar follicular cells. This arrangement is characteristic of the unilaminar primary follicle and is an important step in the maturation of the egg.

During the time of menstruation, LH (luteinizing hormone) causes the final maturation of the Graafian follicle and the release of the secondary oocyte. This hormone surge triggers ovulation, where the mature egg is released from the ovary. FSH (follicle-stimulating hormone) is responsible for the development of the follicles, but it does not directly cause the release of the secondary oocyte. Estrogen is produced by the follicles and plays a role in the thickening of the uterine lining. Progesterone, secreted by the corpus luteum, helps maintain the uterine lining and inhibits ovulation. At the time of ovulation, the secondary oocyte is not arrested but rather released for potential fertilization.

FSH (follicle-stimulating hormone) is responsible for stimulating the granulosa layer of cells in the growing follicles to secrete estrogen. Estrogen is an important hormone in the process of ovulation, as it helps in the development and maturation of the egg cell. LH (luteinizing hormone) on the other hand, causes the theca interna cells to secrete progesterone, which is important for the preparation of the uterus for potential implantation of a fertilized egg. The other statements in the options are incorrect and do not accurately describe the role of FSH and LH in the follicular development before ovulation.

During the secretory phase of the menstrual cycle, the ovulated egg becomes a fully developed ovum. Progesterone, which is produced by the corpus luteum, inhibits LH hormone secretion from the pituitary gland. This is important because LH hormone is responsible for triggering ovulation. By inhibiting LH hormone secretion, progesterone helps to maintain the uterine lining and prepare it for potential implantation of a fertilized egg. If fertilization does not occur, the corpus luteum will regress and become the corpus luteum of pregnancy.

LH, or luteinizing hormone, stimulates the formation of the corpus luteum. The corpus luteum is a temporary endocrine structure that develops from the ruptured follicle after ovulation. It secretes progesterone, which is important for preparing the uterus for implantation and maintaining pregnancy. LH triggers the transformation of the follicle into the corpus luteum, ensuring that it produces progesterone. This hormone plays a crucial role in the regulation of the female reproductive cycle.

FSH stimulates the smooth endoplasmic reticulum (SER) of the granulosa layer to produce estrogen. The granulosa cells in the Graafian follicles are responsible for the production of estrogen, which is essential for the development and maturation of the follicle. FSH stimulates the granulosa cells to increase the activity of the SER, leading to an increased production of estrogen. Estrogen plays a crucial role in regulating the menstrual cycle and preparing the uterus for potential implantation of a fertilized egg.

The correct answer is LH stimulates theca externa cell to produce and secrete estrogens. This statement is incorrect because it is actually the theca interna cells that are stimulated by LH to produce and secrete androstenedione, which is then converted into estrogens by the granulosa cells under the influence of FSH. The other statements are all correct. The corona radiata cells do send out cytoplasmic extensions through the zona pellucida to the plasma membrane of the oocyte, the LH surge does cause ovulation of the oocytes, and FSH does stimulate the smooth endoplasmic reticulum (SER) of granulosa cells to transform androstenedione into estrogens.

Follicular cells of the primordial follicle produce the oocyte maturation inhibitory substance. These cells surround the oocyte and play a crucial role in its development and maturation. The oocyte maturation inhibitory substance is responsible for preventing the oocyte from maturing too early, allowing it to develop properly within the follicle. This substance helps regulate the timing of oocyte maturation and ensures that it occurs at the appropriate stage of the reproductive cycle.

During meiosis, the secondary spermatocytes have 23 chromosomes. Meiosis is a type of cell division that occurs in the reproductive cells to produce gametes (sperm and eggs). In the first round of meiosis, the primary spermatocytes divide into two secondary spermatocytes, each containing half the number of chromosomes as the original cell. Therefore, the secondary spermatocytes have 23 chromosomes, which is the haploid number of chromosomes in humans. This ensures that when the sperm fertilizes an egg, the resulting zygote will have the correct number of chromosomes.

Unequal cell size is not considered to be significant to meiosis because the size of the cells produced during meiosis is not a key aspect of the process. Meiosis is primarily concerned with the reduction of chromosome number and the creation of genetically diverse gametes. The other options listed, such as crossing over, pairing of homologous chromosomes, independent assortment, and non-disjunction, are all important and significant events that occur during meiosis.

In meiosis, the pairing of homologous chromosomes occurs in prophase 1 of meiosis 1. This is an important step in meiosis where the homologous chromosomes come together and form tetrads. During this process, genetic recombination can occur, leading to genetic diversity. The other statements are incorrect: DNA duplication occurs in S phase before meiosis, the genetic material produced in each cell is not identical due to genetic recombination, non-disjunction can occur in meiosis II, and separation of chromatids occurs during anaphase 2 of meiosis 2.

The posterior fontanelle is a soft spot on the back of a baby's head where the skull bones have not yet fully fused together. It is usually closed by the age of 6 months. As a baby grows, the skull bones gradually come together and the fontanelle closes. The closure of the posterior fontanelle is an important milestone in a baby's development, indicating that the skull bones have properly formed and the brain is protected. After the age of 6 months, the fontanelle should be fully closed, and any delay in closure may require further medical evaluation.

The correct answer is that the granulosa layer of cells rest on a basal lamina. This means that the granulosa cells, which are part of the growing primary follicle, are supported by a layer called the basal lamina. This arrangement is important for the development and function of the follicle. The other statements are incorrect because the granulosa layer does not secrete androgens, fluid-filled spaces do appear between the granulosa cells, the zona pellucida is present, and the theca externa layer of cells is not mentioned in relation to the basal lamina.

During the proliferative phase of the menstrual cycle, inhibin is secreted by the mature graafian follicle. This inhibin acts to inhibit the development of the growing follicles, leading to their atresia or degeneration. This is an important regulatory mechanism to ensure that only one dominant follicle is selected for ovulation. The inhibin secretion helps to prevent excessive follicular development and allows for the maturation and release of a single, healthy oocyte.