Lab 9: Microbial Diversity

domains of life

bacteria (prokaryotes), archaea (prokaryotes), eukarya (eukaryotes)

archaea conditions

extremophiles

eukarya

animalia, plantae, protista, fungi

cyanobacteria 

a phylum in the bacteria domain that is extremely diverse and photosynthetic 

habitat of cyanobacteria

freshwater, marine and terrestrial, areas ranging from tropics to poles

history of cyanobacteria

first known organisms to produce oxygen, and the only prokaryotes that produce oxygen, prior to their appearance earth was anaerobic

cyanbacteria relationship with cells 

endosymbiotic relation with cells, evolved into chloroplasts 

arthrospira platensis (spirulina)

cultivated for use as a nutritional supplement

protein content of spirulina

protein content ranging from 50-70% of dry weight

vitamins in spirulina 

high in beta carotene and beta vitamins 

protista

“the very first”, very diverse organisms, molecular advances

if its not an ___, ___, or ___, its a ____

animal, plant, fungus, protist

protozoans 

part of protists, animal like, heterotrophic 

algae

part of protista, plant like, autotrophic

nutrition of protista

autotrophs, heterotrophs, and mixotrophs

protista habitat 

freshwater, marine, terrestrial, parasitic 

protista reproduction

sexual and asexual

euglenozoans

mostly aquatic, contain a flexible cytoskeleton called pellicle that provides structure

euglenozoans can be 

heterotrophic (phagocytosis) and phototrophic (photosynthesis) 

flagella in euglenozoans

most have 2 flagella composed of crystalline rod and microtubules

genus of euglenozoans

phacus, freshwater, flat leaf shaped structure

alveolates 

alveoli (sacs) located beneath cell membrane that help maintain osmotic balance 

three groups of alveolates

ciliates, dinoflagellates, apicomplexans

nuclei of ciliates

2 nuclei, micro (sexual reproduction) through conjugation which is the exchange of micronuclei, and macro involved in cellular functions

what are ciliates usually covered in 

cilia which help in locomotion and digestion 

ciliates blepharisma (genus)

photophobic, photoreceptor pigment blepharismin (pink), used as a model organism

ciliates dileptus genus

insatiable appetite, proboscis lined with toxicysts on one side that leads to the oral cavity, swings around to strike prey, and can recognize self and others

ciliates stentor (genus) 

large, blue-green, trumpet shaped that learn through habituation, and regenerative abilities 

habituation of stentor

behavioral response decreases following a repeated stimulus that can be studied without interference from surrounding cells

regenerative abilities of stentor 

can regenerate if it contains a piece of micronucleus and cell membrane 

dinoflagellates

part of gonyaulax (genus) that have 2 flagella in which one wraps around organism to keep it afloat by rotational motility, and one extends outward

gonyaulax genus secretes

saxitoxin which is a neurotoxin that is toxic

apicomplexans 

obligate parasites that contain apicoplasts 

apicomplexans obligate parasites

cannot complete life cycle without hosts

apicomplexans contain apicoplasts

degenerated chloroplasts and no photosynthetic pigments

naegleria fowleri 

brain eating amoeba 

primary amebic meningoencephalitis

brain eating amoeba that is 97% fatal with 37 reported cases (2006-2015), and occurs by infection through nose

tardigrades

tiny, 8 legged, segmented animals that belong to phylum tardigrada 1,300 species

habitat tardigrades 

moss and lichen which requires a thin layer of water 

tardigrades as extremophiles

can survive in high/low temperatures, high/low pressure, even the vacuum of space

what do tardigrades possess

a unique protein that protects their DNA

cryptobiosis 

tardigrades enter an inactive state called cryptobiosis when conditions are poor