In this article we will discuss about the meaning of mitochondria. Mitochondria are cytoplasmic organelles containing their own DNA and some enzymes that catalyse the process of oxidative phosphorylation. Mitochondria are not autonomous bodies because they require their own genes and nuclear genes to function normally. The role of mitochondria in cytoplasmic inheritance was first understood when Ephrussi and his [...]
In this article we will discuss about the structure of chlamydomonas (explained with labelled diagram). The unicellular green alga Chlamydomonas is haploid with a single nucleus, a chloroplast and several mitochondria (Fig. 9.3). It can reproduce asexually as well as sexually by fusion of gametes of opposite mating types (mt+ and mt-). The mating type is controlled by a single [...]
Sonneborn in 1938 discovered certain strains in Paramecium which showed a killer trait due to the presence of a cytoplasmic factor called kappa. The killer strain can destroy the sensitive strains growing in culture which do not have kappa by liberating a toxic substance paramecin. Killer strains are not killed by their own paramecin. Paramecium has two kinds of nuclei, [...]