Polyspermy results when two or more sperms fertilize an egg. It is usually lethal since it results in blastomeres with different numbers and types of chromosomes. Many species therefore, have […]
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CSIR NET Life Science Previous Year Questions and Solution on Basic Concepts of Development
Defining Determination in Embryonic Development: Key Characteristics and Misconceptions
Given are certain facts which define ‘determination’ of a developing embryo. A. Cells have made a commitment to a differentiation program. B. A phase where specific biochemical actions occur in […]
CSIR NET Life Science Previous Year Questions and Solution on Development Biology
Key Factors Affecting Bindin-Egg Interaction in Sea Urchin Fertilization and Their Role in Preventing Fertilization
15. For successful fertilization in sea urchin, interaction between the surface of the egg and acrosomal proteins, specifically a 30.5 kDa protein called bindin, is necessary. The following factors could […]
CSIR NET Life Science Previous Year Questions and Solution on Basic Concepts of Development
Cell Commitment in Development: Understanding Determination in Embryogenesis
During development, if a cell has committed to a particular fate, it is said to be (1) pluripotent (2) totipotent (3) determined (4) differentiated During the development of multicellular organisms, […]
CSIR NET Life Science Previous Year Questions and Solution on Development Biology
Key Events in Sea Urchin Fertilization: The Roles of Bindin, Acrosomal Reaction, and Cortical Granule Response
Following statements are made about fertilization occurring in sea urchins: A. Chemoattraction of the sperm to the egg is mediated by sperm activating peptides like bindin. B. Exocytosis of the […]
CSIR NET Life Science Previous Year Questions and Solution on Basic Concepts of Development
Genetic Specificity of Interaction Demonstrated in Cross-Species Embryonic Transplantation
In a transplantation experiment, the area of presumptive ectoderm from an early frog gastrula was transplanted to a region of the newt gastrula destined to become parts of the mouth. […]
CSIR NET Life Science Previous Year Questions and Solution on Basic Concepts of Development
Regional Specificity of Induction in Chick Feather Development
In chick, development of wing feather, thigh feather and claws depends on epithelial specificity conferred by induction from mesenchymal components from different sources of the dermins. This may be attributed […]
CSIR NET Life Science Previous Year Questions and Solution on Development Biology
Common Misconceptions in Sea Urchin Fertilization: Clarifying Calcium Signaling and Respiratory Burst
Consider the following events which occur during fertilization of sea urchin eggs. (A) Resact/Speract are peptides released from the egg jelly and help in sperm attraction. (B) Bindin, an acrosomal […]
CSIR NET Life Science Previous Year Questions and Solution on Basic Concepts of Development
Key Concepts of Induction in Embryonic Development: Understanding Signal and Cellular Responses
Induction is an extrinsic process that depends on the position of a cell in the embryo. It is a process whereby one cell or group of cells can influence the […]
CSIR NET Life Science Previous Year Questions and Solution on Development Biology
Bindin and Its Receptors: Essential Proteins for Species-Specific Sperm-Egg Interaction in Sea Urchins
12. Successful fertilization in sea urchin demands specific interaction between proteins and receptors of sperms and eggs. In view of the above, which one of the following combinations is correct? […]
