BI236 Lecture Notes - Lecture 4: Apicomplexan Life Cycle, Nuclear Membrane, Micronucleus
Document Summary
Bi256: unicellular eukaryotes: protozoan groups (ch11) part ii. Reproduction: sexual reproduction does occur widely in protozoans and may precede certain phases of asexual reproduction, however, protozoans do not have embryonic development and do not produce embryos. Sex: reductive division 2n -> n, gamete cells (nuclei) exchanged followed by fussion (n+n -> 2n) Fission produces more individuals than other forms of reproduction. Binary fission is the most common form where two identical individuals are produced. Budding - occurs when a small progeny cell (bud) pinches off from parent cell: bud then later grows to adult size. Cytokinesis (division of cytoplasm) preceded by several nuclear divisions. Many individuals are formed simultaneously called merozoites. If union of gametes precedes multiple fission then is called sporogony. All of above accompanied by some form of mitosis after the formation of new cells but is unlike that of metazoan mitosis.
