Biology Quiz on Volvox and Zoomastigina

Study Notes

Volvox is a microscopic, single-celled organism characterized by its nucleus, a pair of flagella, a large chromoplast, and a red stigma.
Adjacent Volvox cells are interconnected via cytoplasmic strands.
Reproduction can occur both asexually and sexually, producing macrogametes or microgametes.
Ichthyobodo necator is a parasite that infects various freshwater fish, causing ichthyobodosis, primarily by attaching to the skin and gills.

Trypanosomatids are kinetoplastid protozoa with only one flagellum and are exclusively parasitic.
These organisms mainly infect insects, with some species having complex life cycles that include secondary hosts such as vertebrates, invertebrates, or plants.
Trypanosoma species, such as T. gambiense and T. rhodesiense, cause African sleeping sickness, transmitted through the tsetse fly.
Trypanosoma cruzi is responsible for Chagas disease, affecting humans and animals in the Americas.

Coccidia species, such as Eimeria and Isospora, affect various animals, including cattle, pigs, rabbits, and poultry.
Toxoplasma gondii is a parasite of cats that can infect a wide range of animals, including humans, through oocysts or cysts made infectious in undercooked meat.
Toxoplasmosis presents in two forms: acquired (symptomatic in adults) and innate (affecting the fetus during pregnancy).

Plasmodium, the causative agent of malaria, includes several species: P. falciparum, P. vivax, P. ovale, and P. malariae.
Malaria is a severe, challenging disease that disproportionately affects sub-Saharan Africa, leading to high mortality rates.
Leucocytozoon species infect birds, transmitted by simuliid and Culicoides flies.
Piroplasmosis, caused by Babesia species, primarily affects horses and is transmitted by ticks.

Myxosporidia are obligate parasites with complex life cycles, often affecting fish like Myxobolus pfeifferi, which can cause severe diseases.
Microsporidia are unicellular eukaryotes, intracellular parasites impacting both vertebrates and invertebrates.
Nosema bombycis causes pébrine in silkworms, presenting concerns for breeders and causing pepper-like spots.
Nosema apis affects honey bees, leading to nosemosis characterized by dysentery, decreased productivity, and various physical symptoms.

Ciliates are protozoans known for cilia, specialized organelles, allowing diverse locomotion and feeding strategies.
Ciliates reproduce asexually through binary fission and sexually via conjugation, involving genetic material exchange.
Balantidiasis, caused by Balantidium coli, infects the digestive tract, with varying severity based on host resistance.

Protozoa are complex unicellular eukaryotes with diverse metabolic functions and structural adaptations for movement.
Life cycle stages in parasitic protozoa include trophozoites (active feeding stages) and cysts (protective stages).
Asexual reproduction, primarily through binary fission, is common, while both sexual and asexual reproduction may occur in some protozoa.
Nutrition is mainly holozoic or autotrophic, impacting various ecosystems.