THE PLANT-LIKE MICROSCOPIC PROTISTS

Question 1

Using nucleic acid sequencing and detailed comparisons of cell structure, systematists have recently begun to sort out the group of organisms known for decades as the

Answer 1

protists.

Question 2

three domain system

Answer 2

Bacteria, Archaea, Eukarya)

Question 3

efer to organisms that are neither plant, animal nor fungi but exhibit their characteristics.

Answer 3

Protista

Question 4

are all eukaryotic but vary in structure and function more than any other group of organisms.

Most unicellular but some are colonial and multicellular.

Many are incredibly complex; within a single cellular membrane the organism must carry out the myriad of life functions performed by the complex tissue and organ systems of plants and animals. Some are autotrophic, others completely heterotrophic.

Answer 4

Protists

Question 5

Division

Clade

is distinguished from all other protists by the presence of a spiral or crystalline rod of unknown function inside their flagella.

Answer 5

Division Euglenophyta

Clade Euglenozoa,

Question 6

They are single-celled organisms, usually 35-55 um long, spindle-shaped or elongated; shape is maintained by an outer boundary of protoplast, the pellicle or periplast. They are able to greatly distort their body to change direction.

flagella, typically two (2),

They have a reddish eyespot (=stigma) and contractile vacuole near the reservoir. Their numerous chloroplasts contain several photosynthetic pigments

Nucleus lies in the less viscous cytoplasm.

Answer 6

Euglena.

Question 7

distortion of Euglena

Answer 7

euglenoid motion

Question 8

The flagella of Euglena, typically two (2), arise from the base of reservoir and pass through narrow passage called

Answer 8

gullet.

Question 9

photosynthetic pigments of Euglena

Answer 9

chlorophyll a and b, beta-carotene and xanthophyll

Question 10

Storage products of Euglena

Answer 10

are starch-like polysaccharides, paramylum and oils.

Question 11

may occur as discs, rings, rods or spherical granules in cytoplasm.

Answer 11

Paramylum

Question 12

Euglena thrive best where

Answer 12

thrive best where there is an abundance of organic wastes, where water has brown or green color, also in calm waters.

Question 13

Division

Clade

include the apicomplexans, ciliates and dinoflagellates, all of which are characterized by membrane-bounded sacs (=alveoli) just under the plasma membrane.

Answer 13

Division Pyrrophyta

Clade Alveolata

Question 14

function of ____ in Pyrrophyta is unknown but researchers hypothesize that they may help stabilize the cell surface or regulate the cell’s water and ion content.

Answer 14

alveoli

Question 15

important members of the plankton in both fresh and marine waters, although there is greater diversity among the marine species.

photosynthetic protists are so-named because of their two whip-like flagella, which in many species project through cellulose walls that resemble armor plates.

Answer 15

dinoflagellates

Question 16

Many are bioluminescent, producing brilliant green light when disturbed. The chlorophyll is masked by red pigments that help trap light energy.

Answer 16

dinoflagellates

Question 17

When dinoflagellates so numerous, the water is dyed red by the color of their bodies causing

Answer 17

red tides

Question 18

spp causes the recurring red tide phenomenon along Manila Bay.

Answer 18

Pyrodinium bahamense var. compressum

Question 19

dinoflagellate’s epicone and hypocone divided by transverse girdle or cingulum, its longitudinal sulcus running perpendicular to the girdle, its longitudinal and transverse flagella, and its eyespot and nucleus.

Answer 19

Pyrodinium bahamense var. compressum

Question 20

Division

Clade

diatoms, water molds, the golden-brown algae and the multicellular brown algae. A diagnostic characteristic of this clade is the flagellum with numerous fine, hair-like projections (=tinsel-type flagellum).

Answer 20

Division Bacillariophyta

Clade Stramenopila

Question 21

are classified under Clade Stramenopila

200,000 extant species

mostly unicellular, some diatoms form colonies.

possess siliceous walls in two overlapping sections. The walls are a delicate lacework of holes and grooves that differentiate each species.

Answer 21

diatoms

Question 22

overlapping sections of diatoms

Answer 22

valves

Question 23

The larger valve above in diatoms

Answer 23

epitheca

Question 24

smaller valve below in diatoms

Answer 24

hypotheca.

Question 25

epitheca hypotheca together make up the _____ and are joined together by connecting or girdle bands.

Answer 25

frustule

Question 26

in diatoms there are 2 views, valve and girdle views which show the

Answer 26

top or “face” and the side or edge, respectively

Question 27

two morphological forms of diatoms:

Answer 27

centric
pennate

those possessing radial symmetry range from round, capsule-like or drum-shaped and those with bilateral symmetry have an elongate axis.

Question 28

Photosynthetic pigments of diatoms include

Answer 28

chlorophylls a and c, carotene, xanthophylls and fucoxanthin

Question 30

Storage products of diatoms

Answer 30

oils and chrysolaminarin

Question 31

Diatoms reproduction

Answer 31

mostly reproduce by mitosis. Sexual reproduction is not common. When it occurs, it involves the formation of eggs and sperms. Sperms may be amoeboid or flagellated.

Question 32

Division

Clade

have their pigments localized in chromatophores that are yellowish green to golden brown because of a predominance of carotenes and one or two xanthophylls that mask chlorophyll a.

Answer 32

Division Chrysophyta

Clade Stramenopila,

Question 33

food reserves in Chrysophyta

Answer 33

oil and fat; they do not store starch.

Question 34

Vegetative multiplication in Chrysophyta of filamentous and colonial forms is accomplished by

Answer 34

fragmentation.

Question 35

Asexual reproduction in Chrysophyta is carried out by formation of

Answer 35

flagellated zoospores, aplanospores or akinetes

Question 36

Chrysophyta Gametes are formed in the

Answer 36

Gametes are formed in the oogonium and antheridium.

Question 37

siphonous, multinucleate microalga but becomes septate at reproduction and if filament is damaged.

Answer 37

Vaucheria.

Question 38

The filament reaches several centimeters in length. It also has a branched, colourless, rhizoid-like holdfast. Some of its species are partly terrestrial and form coarse, green masses on damp soil, particularly round the edges of ponds, or on the silty shores of salt-marshes; other species are totally aquatic, mostly in fresh water habitats.

Answer 38

Vaucheria