Unit 5 Important Topics

Introduction To Unit 5 - Important Topics To Study

Unit 5 – Just like a storybook! So, of course, you need to read the initial chapters first in order to understand later plots! This unit is all about the development processes of animals mostly and a little bit about plants. Has a good weightage of nearly 30 marks or more. So to ensure you are able to attend about 90% of the questions, you should definitely prepare.

UNIT 5. DEVELOPMENTAL BIOLOGY

TOPICS COVERED

A) Basic concepts of development : Potency, commitment, specification, induction, competence, determination and differentiation; morphogenetic gradients; cell fate and cell lineages; stem cells; genomic equivalence and the cytoplasmic determinants; imprinting; mutants and transgenics in analysis of development

B) Gametogenesis, fertilization and early development: Production of gametes, cell surface molecules in sperm-egg recognition in animals; embryo sac development and double fertilization in plants; zygote formation, cleavage, blastula formation, embryonic fields, gastrulation and formation of germ layers in animals; embryogenesis, establishment of symmetry in plants; seed formation and germination.

C) Morphogenesis and organogenesis in animals : Cell aggregation and differentiation in Dictyostelium; axes and pattern formation in Drosophila, amphibia and chick; organogenesis – vulva formation in Caenorhabditis elegans, eye lens induction, limb development and regeneration in vertebrates; differentiation of neurons, post embryonic development- larval formation, metamorphosis; environmental regulation of normal development; sex determination.

D) Morphogenesis and organogenesis in plants: Organization of shoot and root apical meristem; shoot and root development; leaf development and phyllotaxy; transition to flowering, floral meristems and floral development in Arabidopsis and Antirrhinum E) Programmed cell death, aging and senescence.

Important Topics to be studied From CSIR NET Unit 5

The important terms and terminologies such as potency, commitment, induction, competence, cytoplasmic determinants and morphogenetic gradients – in-depth concepts with reference to the different developmental processes.
Differentiating between terms such as specification, differentiation, and determination. Types of specification such as autonomous, conditional and regulative with examples.
Gametogenesis with special emphasis on stages and chromosome number, fertilization process, slow block and fast block to polyspermy.
Fusion of egg and sperm in model organisms like sea urchin, amphibian and mammals, capacitation.
Types of eggs and various cleavage patterns and examples of organisms in which it takes place, fate maps
Gastrulation and axis formation in sea urchin (role of micromeres), C. elegans, amphibians (Spemann organizer, the role of B-catenin, BMP, Nodal), zebrafish, chick (primitive streak, Hensen’s node) and mammals.
Drosophila developmental stages – all types of maternal and zygotic genes involved with the detailed process of function. Very scoring topic overall!
Organogenesis – Limb formation and roles of hox genes, AER, FGF etc, regeneration in amphibians, Neurulation and neural development. Sex determination in Drosophila and mammals. Vulva development in c. elegans, eye lens induction in vertebrates, cAMP signaling in Dictyostelium
Apart from this, all signaling pathways involved in development have to be prepared very well from topics under Unit 4
From plant development focus on topics such as double fertilization, leaf development, meristems and their transition to flowering, and complete floral development (along with ABC model) with emphasis on the genes involved in Arabidopsis and Antirrhinum.

REFERENCE BOOKS For CSIR NET UNIT 5