Biological classification Flashcards
(37 cards)
5 kingdoms?
monera, protista, plantae, animalia, fungi
who are the sole members of kingdom monera?
bacteria
who are the most abundant microorganisms?
bacteria
4 categories of bacteria
spherical coccus, rod-shaped bacillus, spirilla-spiral shaped, Vibrio-comma shaped
which bacteria live in the most harsh habitats + examples
archaebacteria; extreme salty areas (halophiles), hot springs (thermoacidophiles), and marshy areas(methanogens).
how are archaebacteria protected in extreme conditions?
different cell wall structure from other bacteria
which bacteria can fix atmospheric nitrogen using which cells + examples
cyanobacteria (under eubacteria) can fix atmospheric nitrogen in specialized cells got ‘heterocysts’ for eg: nostoc and anabaena
how do bacteria mainly reproduce and under unfavourable conditions; do they reproduce sexually?
- mainly by fission
- unfavourable conditions-they produce spores
- sexual reproduction-adoptiing a primitive type of DNA transfer
smallest living cells known?
Mycloplasma, completely lack cell wall, can survive without oxygen; many mycoplasma are pathogenic in plants and animals i.e., they are pplo
how are eubacteria characterized? what are they also known as?
they are aka ‘true bacteria’ and they’re characterized by a rigid cell wall and if motile, a flagellum
Features of kingdom protista
- comprises of all unicellular eukaryotes
- primarily aquatic
- reproduce asexually and sexually using a process involving cell fusion and zygote formation.
Advantages of bacteria
- curing of tea leaves
- gut friendly bacteria for digestion
- diary products eg: lactobacillus for curd
- antibiotics
- decomposition, recycling of nutrients
Disadvantages of bacteria
- diseases- cholera, typhoid, tetanus, gonorrhea, tuberculosis, citrus canker, xantholomonas citrii.
- spoilage of food
which type of organisms are under kingdom protista and name them + habitat. What is their mode of reproduction? and general features
all unicellular eukaryotes; chrysophytes, slime moulds, euglenoids, protozoans, dinoflagellates; are aquatic. They reproduce sexually and asexually by a process involving cell fusion and zygote formation. possess locomotory appendages, maybe autotrophic or heterotrophic.
which two organisms do chrysophytes include? what is their habitat/environment? other features?
- golden algae (desmids)
- diatoms
marine and freshwater.
most of them are photosynthetic and microscopic
what does golden algae contain?
FLUCOXANTHIN
Features of diatoms
-2 identical halves facing each other or overlapping each other
-cell wall embedded with silica thus making it indestructible as a result of which their deposits accumulate over billions of years which is referred to as ‘diatomaceous earth’.
- show autotrophic nutrition
- ‘chief’ producers in the aquatic ecosystem and play a great role in evolution of oxygen.
What is diatomaceous earth is used for?
Being gritty, the soil is used for filtration of oils and syrups, and in polishing.
write about habitat, nutrition, colour, cell wall, phenomena
Dinoflagellates
- Marine and photosynthetic
- Appear yellow, red, green, blue, or brown depending on the main pigments of their cells.
- The cell wall has stiff cellulose plates on the outer surface.
- Most of them have 2 flagellla-one lies longitudinally and the other transversely in a furrow between the wall plates.
- Red tide is a phenoimenon which occurs when red dinoflagellates multiply in large numbers, producing neurotoxins which can kill other marine animals when ingested thus becoming ufnit for human consumption(eg:gonyaulax)
example, nutrition, habitat, cell wall, flagella
Euglenoids
- freshwater organisms found in stagnant water
- lacks cell wall instead of which they have a proteinaceous layer called pellicle which makes them flexible.
- Two flagella- short and long one
-photosynthetic in the presence of sunlight but hetero when deprived of it, preying on smaller animals. - pigments are similar to that of higher plants.
- eg: euglena
Slime Moulds
- saprophytic
- habitat: cogs of wood, decaying twigs and leaves
- under favourable conditions, they grow an aggregation called plasmodium spreading over several feet(multinucleated)
- During unfavourable conditions, plasmodium differentiates and forms fruiting bodies bearing pores at their tips which possess true walls and are extremely resistant and survive for years under adverse conditions.
- The spores are disperesed by air currents under favourable ocnditions.
Protozoans and their 4 major groups
- heterotrophs
- predators or parasites
- believed to be primitive relatives of animals
- Amoeboid, ciliated, sporozoan, flagellated
Amoeboid
- freshwater, sea water, or moist soil
- put out pseudopodia to catch prey
- Many have silica shells on their surface.
- eg: Entamoeba-parasite
Flagellated
- possess flagella
- either free living or parasitic
- the parasitic ones cause diseases eg: trypanosoma (sleeping sickness)
