Biological classification

Question 1

5 kingdoms?

Answer 1

monera, protista, plantae, animalia, fungi

Question 2

who are the sole members of kingdom monera?

Answer 2

bacteria

Question 3

who are the most abundant microorganisms?

Answer 3

bacteria

Question 4

4 categories of bacteria

Answer 4

spherical coccus, rod-shaped bacillus, spirilla-spiral shaped, Vibrio-comma shaped

Question 5

which bacteria live in the most harsh habitats + examples

Answer 5

archaebacteria; extreme salty areas (halophiles), hot springs (thermoacidophiles), and marshy areas(methanogens).

Question 6

how are archaebacteria protected in extreme conditions?

Answer 6

different cell wall structure from other bacteria

Question 7

which bacteria can fix atmospheric nitrogen using which cells + examples

Answer 7

cyanobacteria (under eubacteria) can fix atmospheric nitrogen in specialized cells got ‘heterocysts’ for eg: nostoc and anabaena

Question 8

how do bacteria mainly reproduce and under unfavourable conditions; do they reproduce sexually?

Answer 8

• mainly by fission
• unfavourable conditions-they produce spores
• sexual reproduction-adoptiing a primitive type of DNA transfer

Question 9

smallest living cells known?

Answer 9

Mycloplasma, completely lack cell wall, can survive without oxygen; many mycoplasma are pathogenic in plants and animals i.e., they are pplo

Question 10

how are eubacteria characterized? what are they also known as?

Answer 10

they are aka ‘true bacteria’ and they’re characterized by a rigid cell wall and if motile, a flagellum

Question 11

Features of kingdom protista

Answer 11

• comprises of all unicellular eukaryotes
• primarily aquatic
• reproduce asexually and sexually using a process involving cell fusion and zygote formation.

Question 12

Advantages of bacteria

Answer 12

• curing of tea leaves
• gut friendly bacteria for digestion
• diary products eg: lactobacillus for curd
• antibiotics
• decomposition, recycling of nutrients

Question 13

Disadvantages of bacteria

Answer 13

• diseases- cholera, typhoid, tetanus, gonorrhea, tuberculosis, citrus canker, xantholomonas citrii.
• spoilage of food

Question 14

which type of organisms are under kingdom protista and name them + habitat. What is their mode of reproduction? and general features

Answer 14

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.

Question 15

which two organisms do chrysophytes include? what is their habitat/environment? other features?

Answer 15

• golden algae (desmids)
• diatoms
  marine and freshwater.
  most of them are photosynthetic and microscopic

Question 16

what does golden algae contain?

Answer 16

FLUCOXANTHIN

Question 17

Features of diatoms

Answer 17

-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.

Question 18

What is diatomaceous earth is used for?

Answer 18

Being gritty, the soil is used for filtration of oils and syrups, and in polishing.

Question 19

write about habitat, nutrition, colour, cell wall, phenomena

Dinoflagellates

Answer 19

• 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)

Question 20

example, nutrition, habitat, cell wall, flagella

Euglenoids

Answer 20

• 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

Question 21

Slime Moulds

Answer 21

• 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.

Question 22

Protozoans and their 4 major groups

Answer 22

• heterotrophs
• predators or parasites
• believed to be primitive relatives of animals
• Amoeboid, ciliated, sporozoan, flagellated

Question 23

Amoeboid

Answer 23

• freshwater, sea water, or moist soil
• put out pseudopodia to catch prey
• Many have silica shells on their surface.
• eg: Entamoeba-parasite

Question 24

Flagellated

Answer 24

• possess flagella
• either free living or parasitic
• the parasitic ones cause diseases eg: trypanosoma (sleeping sickness)

Question 25

Ciliated

Answer 25

- aquatic, actively moving organisms because of the presence of thousands of cilia - Possess a cavity (gullet) that opens to the outside of the cell surface. - eg: paramoecium

Question 26

Sporozoans

Answer 26

- diverse organisms that include an infectious-spore like stage in their life cycle. - Most notorious is Plasmodium(malarial parasite, causes malaria).

Question 27

Viroid

Answer 27

- smaller than viruses - caused potato spindle tuber disease - free RNA lacking capsid, RNA with low molecular weight

Question 28

prion

Answer 28

-proteinaceous infectious particle/abnormally folded protein - diseases: bovine spongiform encephalopathy (BSE) mad cow disease; analogous variant-Cr-Jacob Disease in humans - can cause neurodegneration-occurring sporadically /genetic mutation/from an infected source

Question 29

albugo

Answer 29

parasitic fungi on mustard-phycomycetes

Question 30

phycomycetes characteristics

Answer 30

*aquatic habitats, decaying wood in moist or damp places, or obligate parasites on plants. *asexual reproduction-zoospores or aplanospores-endogenously produced in the sporangium *aseptate and coenocytic mycelium *isogamous or anisogamous or oogamous eg: mucor, rhizopus, albugo

Question 31

Ascomycetes

Answer 31

*commonly known as sac-fungi *mostly multicellular or rarely unicellular (yeast) *Saprophytic, decomposers, parasites, or coprophilus(growing on dung) *branched and septate mycelium *asexual reproduction-conidospores-produced exogenously on special mycelium called conidiophores *Sexual spores-ascospores-[rpduced endogenously in sac like asci-which are arranged in differrent types of fruiting bodies called ascocarps.

Question 32

Basidiomycetes

Answer 32

*no asexual spores and sex organs *plasmogamy-fusdion of tweo vegetative or somatic cells *dikaryon ultimately giving rise to basidia *basidia undergo karyogamy and meiosis and exogenously produce four basidiospores *basidia arranged in fruiting bodies called basidiocarps *vegetative reproduction by fragmentation is common *eg: puccinia, ustilago, agaricus

Question 33

deuteromycetes

Answer 33

*imperfect fungi-only asexual phases of the fungi are known *once their sexual forms were discovered-moved to right classes *reproduce only by asexual spores called conidia *septate branched mycelium *saprophytes, prasites-large number are decomposers of litter and help in mineral cycling eg: colletrichum, alternaria, trichoderma

Question 34

who gave the name virus and recxognized microbes as the cause in TMV,discovered they weerre smaller than bacteria as they passed through bacteria proof fdilters

Answer 34

pasteur d.j. ivanowsky

Question 35

who discovered the extract of infected plants cud infect healkthy plants and called it contagium vivum fluidum

Answer 35

M.W.Bejerin

Question 36

who shpowed that viruses could be crystallised and crystals consist largely of proteins

Answer 36

W.M. stanley