lecture 6 (cryptomonads) Flashcards
what is the periplast made out of?
protein
how do cryptomonads move?
two unequal flagella with hairs, and phototaxis
what is the primary habitat of a cryptomonad?
deep, cold waters, in oligotrphic, temperate and high latitude lakes/oceans
describe major features of a cryptomonad cell
two uneven flagella emerging from a vestibulum, nucleomorph and nucleus, ejectisomes in the vestibulum, surrounded by a periplast
what cellular features are responsible for poor preservation of cryptomonads and why
the ejectosomes, these are violently discharged due to sudden environmental shock or preservatives (eg. pH changes, pressure changes)
this destroys the cell
what are periplasts made of and where is it located?
they are made of hexagonal/rectangular/round protein plates,
these sandwich the plasma membrane
how many membranes does the plastid have?
four
what is the nucleomorph and what is its origin?
a second nucleus, remnant of red algal nucleus. from secondary endosymbiosis (ingestion of red alga)
name the pigments present in cryptomonads
chl a, chl c, alpha and beta carotenes, phycoerythrin and phycocyanin, xanthophylls (eg. alloxanthin)
what is the storage material of cryptomonads?
starch granules in cytoplasm
what is the primary reproductive mode in cryptomonads?
asexual, also has resting stage/cysts
differences and similarities between euglenoids and cryptomonads
cryptomonads have no metabolic movement, storage = starch, different flagellar aparatus, commonly planktonic
both have no cell membrane, can produce cysts, have no good fossil record, have light sensitive systems, primarily unicels
