What are plasmids? Describe their role in bacteria.
Plasmids are self-replicating, extra chromosomal segments of double stranded, circular, naked DNA.
These plasmid confer certain unique phenotypic characters to the bacteria like antibiotic resistance, sex factor, fertility factor etc. They are also used as vectors in genetic engineering.
Give the biochemical composition of plasma membrane. How are lipid molecules arranged in the membrane?
Are the different types of plastids interchangable? If yes, give examples where they are getting converted from one type to another.
The genomic content of the nucleus is constant for a given species where as the extra chromosomal DNA is found to be variable among the members of a population. Explain.
Structure and function are correctable in living organisms. Can you justify this by taking plasma membrane as an example?
Are the different types of plastids interchangable? If yes, give examples where they are getting converted from one type to another.
Discuss briefly the role of nucleolus in the cells actively involved in protein synthesis.
Is there a species specific or region specific type of plastids? Flow does one distinguish one from the other?
Is extra genomic DNA present in prokaryotes and eukaryotes? If yes, indicate their location in both the types of organisms.
Write the functions of the following
(a) Centromere (b) Cell wall
(c) Smooth ER (d) Golgi apparatus
(e) Centrioles
Eukaryotic cells have organelles which may
(a) not be bound by a membrane
(b) bound by a single membrane
(c) bound by a double membrane
Group the various sub-cellular organelles into these three categories.
Briefly give the contributions of the following scientists in formulating the cell theory.
(a) Rudolf Virchow
(b) Schleiden and Schwann
Differentiate between Rough Endoplasmic Reticulum (RER) and Smooth Endoplasmic Reticulum (SER).