In: Biology
Write short notes the following
1. Central dogma
2. Origins of mitochondria and chloroplasts
1)-central dogma -it provides the basic framework for how genetic information flows from DNA sequence to protein product inside the cell. The genetic information flows from DNA to RNA to protein.so it explains the flows of genetic information. it suggest that DNA contain the information needed to make all of our protein and RNA is messanger that carry information to ribosome.
2)-Mitochondria and chloroplast evolved from engulfed prokaryote that once lived as independent organisms. there are 2 theories of origin of mitochondria and chloroplast -1)endosymbiont theory, 2)-direct filiation theory.
Endosymbiont theory-this theory is based on similarity of mitochondria and chloroplast with prokaryotes.these organelles posses their own genetic material (DNA) as well as machinery for protein synthesis.
In direct filiation theory several models are given for evolution of mitochondria and chloroplast.