Trivia Quiz On Anatomy - Embryology

A single, fertilized cell is called a zygote. After fertilization, when the sperm and egg combine, a zygote is formed. The zygote contains all the genetic material necessary for the development of a new individual. It undergoes cell division and differentiation to eventually form a blastocyst, which then develops into a fetus. However, at the initial stage, immediately after fertilization, it is referred to as a zygote.

The three germ layers are endoderm, mesoderm, and ectoderm. These layers are formed during embryonic development and give rise to different tissues and organs in the body. The endoderm gives rise to the innermost layer of organs such as the digestive system and respiratory system. The mesoderm gives rise to the middle layer of organs such as muscles, bones, and circulatory system. The ectoderm gives rise to the outermost layer of organs such as the skin, nervous system, and sensory organs.

After the zygote undergoes several rounds of cell division, it forms a solid ball of cells known as a morula. At this stage, the cells are undifferentiated and have not yet formed any specific tissues or organs. The morula will eventually develop into a blastocyst, which is the next stage of embryonic development. Therefore, the correct answer is morula.

The embryonic period refers to the early stage of prenatal development, starting from the third week after fertilization and lasting until the eighth week. During this period, the major organs and body systems begin to form, and the embryo is highly susceptible to external influences. Therefore, the statement "The embryonic period lasts from weeks 3-8" is true.

The correct answer is true. The HYPOblast is a layer of cells that forms during embryonic development and gives rise to the yolk sac. The yolk sac is an important structure in early development, providing nutrients to the developing embryo before the placenta is fully formed. Therefore, it is accurate to say that the HYPOblast forms the yolk sac.

The tropoblast of the Blastocyst becomes the fetal half of the placenta. The tropoblast is the outer layer of cells in the blastocyst, which is the early stage of embryo development. It plays a crucial role in the formation of the placenta, which is responsible for providing nutrients and oxygen to the developing fetus and removing waste products. The placenta is composed of both maternal and fetal tissues, with the tropoblast contributing to the fetal side of the placenta.

The correct answer is fetal, pre-embryonic, and embryonic. The prenatal period refers to the time before birth, and it is divided into three stages. The first stage is the pre-embryonic stage, which occurs during the first two weeks after conception. During this stage, the fertilized egg undergoes rapid cell division and implants into the uterine lining. The second stage is the embryonic stage, which lasts from the third week to the eighth week of pregnancy. During this stage, the major organs and body systems begin to form. The third stage is the fetal stage, which begins at the ninth week and continues until birth. During this stage, the fetus grows and develops further.

The bilaminar disc is formed from two layers, the epiblast and the hypoblast. The epiblast is the upper layer of the disc, which gives rise to the ectoderm, mesoderm, and endoderm. The hypoblast is the lower layer, which contributes to the formation of the yolk sac. Together, these two layers play a crucial role in the early development of the embryo.

The correct order of induction that creates the neural tube is neural plate, neural groove, neural tube. The neural plate is the first step in the process, where a flat sheet of ectodermal cells forms. This is followed by the formation of the neural groove, which is a crease that develops in the neural plate. Finally, the neural tube is formed when the neural folds of the neural groove fuse together, creating a hollow structure that eventually develops into the central nervous system.

The trophoblast, which is the outer layer of cells in the blastocyst, divides into two layers: the cytotrophoblast and the syncytiotrophoblast. The cytotrophoblast is the inner layer of cells that retains its individual cell boundaries and is responsible for the formation of the placenta. The syncytiotrophoblast is the outer layer of cells that fuse together to form a syncytium, which is a multinucleated mass of cells. The syncytiotrophoblast is involved in implantation, nutrient exchange, and hormone production during pregnancy.

The prenatal period refers to the time before birth when the baby is developing inside the mother's womb. It starts from conception and lasts until delivery. The average length of a pregnancy is around 38 weeks, which is why the correct answer is 38. This is the duration during which the baby goes through various stages of development, including the formation of organs and body systems. It is a crucial period for the baby's growth and the mother's health.

During the embryonic stage, the developing embryo is most sensitive to teratogens. This is because this stage is characterized by rapid cell division and differentiation, as the basic structures and organs of the body are forming. Exposure to teratogens during this critical period can disrupt the normal development of the embryo, leading to birth defects or other developmental abnormalities.

The correct answer is ICM. In the blastocyst, the inner cell mass (ICM) is the group of cells that will eventually develop into the embryo itself. It is responsible for forming the different tissues and organs of the developing organism. The trophoblast, on the other hand, is the outer layer of cells that will become the placenta. The cell sac and outer layer are not accurate descriptions of the specific part of the blastocyst where the embryo starts.

Transverse folding creates a cylindrical trunk. Transverse folding refers to the folding of tissues or structures perpendicular to the main axis of the body. In the context of trunk development, transverse folding occurs during embryogenesis, where the sides of the embryo fold inward, creating a cylindrical shape. This folding process contributes to the formation of the body's major organs and structures, including the spinal cord, ribs, and abdominal organs.

The chorion is the outermost membrane that surrounds the fetus and forms the fetal part of the placenta. The cytotrophoblast is the inner layer of the trophoblast that helps in the formation of the placenta. The syncytiotrophoblast is the outer layer of the trophoblast that plays a role in implantation and nutrient exchange between the mother and the fetus. Together, these three structures contribute to the formation and function of the placenta.

The correct answer is "Organ development follows gastrulation and body folding" because gastrulation and body folding are crucial processes in embryonic development that lead to the formation of the three germ layers and the establishment of the body plan. This is followed by organogenesis, which is the process of organ development.

The correct answer is "Most organ systems have developed by week 8" because by week 8 of embryonic development, the major organ systems have formed and are beginning to differentiate and mature. This is a critical stage in organogenesis where the basic structures of the organs are established.

The statement "upper and lower limbs attain adult shape" is incorrect because limb development continues beyond week 8 and the limbs do not attain their final adult shape at this stage.

The statement "Embryo is 5 inches long by week 8" is also incorrect because the average length of an embryo at week 8 is around 1 inch, not 5 inches.