fourth semester botany

 FOURTH SEMESTER BOTANY

Cell Biology, Genetics and Plant Breeding

Unit – 1: The Cell 

1. Cell theory; prokaryotic vs eukaryotic cell; a brief account on ultra-structure of a plant cell.

2. Ultra-structure of cell wall.

3. Ultra-structure of plasma membrane and various theories on its organization.

4. Polymorphic cell organelles (Plastids); ultra structure of chloroplast. Plastid DNA.

Unit – 2: Chromosomes 

1. Prokaryotic vs eukaryotic chromosome. Morphology of a eukayotic chromosome.

2. Euchromatin and Hetero chromatin; Karyotype and ideogram.

3. Brief account of chromosomal aberrations - structural and numerical changes

4. Organization of DNA in a chromosome (solenoid and nucleosome models).

Unit – 3:Mendelian and Non-Mendelian genetics 

1. Mendel’s laws of inheritance. Incomplete dominance and co-dominance; Multiple allelism.

2. Complementary, supplementary and duplicate gene interactions (plant based examples are to be dealt).

3. A brief account of linkage and crossing over; Chromosomal mapping - 2 point and 3 point test cross.

4. Concept of maternal inheritance (Corren’s experiment on Mirabilis jalapa); Mitochondrial DNA.

Unit – 4:Structure and functions of DNA 

1. Watson and Crick model of DNA. Brief account on DNA Replication (Semi- conservative method).

2. Brief account on Transcription, types and functions of RNA. Gene concept and genetic code and Translation.

3. Regulation of gene expression in prokaryotes - Lac Operon.

Unit – 5:Plant Breeding 

1. Plant Breeding and its scope; Genetic basis for plant breeding. Plant Introduction and acclimatization.

2. Definition, procedure; applications and uses; advantages and limitations of :(a) Mass selection, (b) Pure line selection and (c) Clonal selection.

3. Hybridization – types and procedure; Heterosis(hybrid vigour).

4. Role of mutations in plant Breeding : Types of mutations & Procedure

5. A brief account on Molecular breeding – DNA markers in plant breeding. RAPD, RFLP.