Free Growth and Development MCQs with Answers

211. The mesodermal cell which give rise to urinary system in frog are called:

• A. Pincer cells
• B. Blastomers
• C. Nephrotome
• D. Parietal

Explanation: Pincer cells are deformed blood cells which are a characteristic feature of hereditary spherocytosis associated with Protein Band-3 deficiency. Therefore, A is incorrect. A blastomere is a type of cell produced by cell division (cleavage) of the zygote after fertilization; blastomeres are an essential part of blastula formation and blastocyst formation in mammals. Therefore, B is incorrect. The nephrotome is a section of the mesoderm that was thought to give rise to the pronephros and eventually to the rest of the kidney. Therefore, A is the correct answer. However, modern visualizing techniques such as scanning electron microscopy have shown this is not the case. Parietal cells (AKA oxyntic cells) are epithelial cells in the stomach that secrete hydrochloric acid (HCl) and intrinsic factors. These cells are located in the gastric glands found in the lining of the fundus and body regions of the stomach.

212. The transitory stage between cleavage and gastrulation is:

• A. Orgenogenesis
• B. Blastula
• C. Gastrula
• D. Development

Explanation: Zygote develops by a sequence of mitotic division, called cleavage, into a multicellular structure, first a solid ball of cells the module, and then a hollow ball of cells the blastula.

213. The individual with hare-lip shows which of the following condition?

• A. Cleft palate
• B. Polydactyly
• C. Hard-palate
• D. Microcephaly

Explanation: A cleft palate is a congenital condition often associated with a hare lip, involving an opening or split in the upper lip and/or roof of the mouth. This occurs when the developing facial structures in an unborn baby do not completely fuse. The other options are unrelated: Polydactyly involves extra digits; the hard palate is a normal part of the mouth's structure; and microcephaly is a different developmental condition affecting head size.

214. The developing embryo is protected against the physical trauma by :

• A. Pericardial fluid
• B. Allantoic fluid
• C. Amniotic fluid
• D. All of these

Explanation: Amniotic fluid plays a crucial role in protecting the developing embryo/fetus against physical trauma. It is a liquid that surrounds the embryo/fetus within the amniotic sac, which is formed by the amnion membrane. The amniotic fluid acts as a cushion, providing a protective barrier and absorbing shocks or impacts that may occur during movement or external forces.

215. Cleavage differ from mitosis in that:

• A. It occurs only in zygote
• B. It occurs in all body cells
• C. It results in haploid cells only
• D. It results in identical cells

Explanation: Cytokinesis during cleavage results in identical cells as the parent cell divides into two daughter cells. The other options are incorrect as cleavage is not limited to the zygote stage, does not occur in all body cells, and does not result in haploid cells.

216. Extract embryonic membrane like amnion and chorine appeared for the first time:

• A. Amphibians
• B. Reptiles
• C. Birds
• D. Fish

Explanation: Embryonic membranes like the amnion and chorion first appeared in reptiles, making option B the correct answer. These membranes are part of the amniotic egg, a key adaptation that allowed reptiles to reproduce on land. Birds also have similar adaptations, but they evolved from reptilian ancestors, not the other way around. Options A, C, and D are incorrect because they do not align with the evolutionary development of embryonic membranes in animals.

217. Which germinal layer develops in the digestive system?

• A. Ectoderm
• B. Mesoderm
• C. Epidermis
• D. Endoderm

Explanation: During embryonic development, the digestive system originates from the endoderm, which is one of the three primary germinal layers.

218. During the development of the chick peripheral part of the blastoderm lies unseparated from the yolk and forms:

• A. Area pellucida
• B. Area opaca
• C. Notochord
• D. Primitive streak

Explanation: During the development of a chick embryo, the peripheral part of the blastoderm that remains attached and unseparated from the yolk forms the Area pellucida.

219. Extra embryonic membranes like amnion and chorion appeared for the first time in

• A. Fish
• B. Amphibian
• C. Reptiles
• D. None

Explanation: Extra embryonic membranes like amnion and chorion appeared for the first time in reptiles. The amnion is a membrane that surrounds and protects the embryo, providing a fluid-filled cavity for its development. The chorion is another extra embryonic membrane that allows for gas exchange with the environment.

220. All of the following are derived from mesoderm except:

• A. Muscles
• B. Liver
• C. Gonads
• D. Blood vessels

Explanation: GERM LAYERS: A germ layer is a group of cells in an embryo. There are 3 germ layers: the endoderm (inner layer), the ectoderm (outer layer), and the mesoderm (middle layer). All the parts mentioned are formed by mesoderm except for the liver, which is a product of endoderm.