Plant Kingdom Test - 31

Sea lettuce or Ulva lactuca is a species of bright green algae of the division Chlorophyta. With its lobed and ruffle-edged leaves, this flat green sea weed resembles a garden lettuce and is found in marine waters growing from a discoid holdfast. Commonly found on rocks and other algae the sea lettuce is prolific, where the nutrients are in abundance. The life cycle of Ulva shows the sporangial and gametangial thalli as morphologically alike and follows a pattern of alternation of generations and the multi-cellular diploid form alternates with multi-cellular haploid form. Thus, the correct answer is option D.

Phaeophyta: Chl a, Chl c, fucoxanthin and xanthophyll
Rhodophyta: Chl a, chl d, carotene, phycoerythrin, phycocyannin
Chlorophyta: Chl a, chl b, carotene, xanthophyll
Cyanophyta:  Chl a, Chl d,carotene, phycoerythrin, phycocyannin
Xanthophyta: Chla, chl c, carotene.
Euglenophyta: Chla, chl b, carotene.
These are the photsynthetic pigments of different plant groups out of which Rhodophyta and Cyanophyta have similar combinations.

Cytological structure of all the above options revealed that they lack flagella.

Red alga is eukaryotic without flagella, centrioles, with phycobiliproteins and chloroplast lacking external endoplasmic reticulum and unstacked thyllakoid.

Cyanobacteria do not have organs for movement such as flagella, but some filamentous BGA exhibit gliding movement due to slime secretion along with contractile waves in the cells.

In case of higher seed plants (Spermatophyta) like gymnosperm and angiosperm, flagella are absent since, presence of pollen grain eliminated use of water for fertilization. Thus, the correct answer is option D.

Chlorophyta reproduces both sexually and asexually, but usually sexually. Asexual reproduction can occur by fission, fragmentation, or zoospores. Sexual reproduction can be isogamous, anisogamous or oogamous. Isogamy involves the reproduction by fusion of similar gametes. Anisogamy is a sexual reproduction which takes place by fusion of dissimilar gametes. Oogamy involves sexual reproduction where the female gametes are larger and less motile than male gamete.

Stone wort is a green algae of class Chaophyceae. Stone wort is a common name of Chara, is found in mud near fresh water and accumulates as calcium carbonate deposits forming a major part of calcareous mare of lakes. Green algae belongs to two classes, i.e., Chlorophyta (examples, Oodogonium, Ulothrix) and Charophyta (examples, Chara).
Other options:
Laminaria is a brown algae.
Polysiphonia is a red algae.
Chlorella is a green algae belonging to class Chlorophyta.

Red algae are also known as rhodophytes, which is a eukaryotic alga without flagellate around 7000 living species are known till now. Red algae's are marine species. Since doesn't have flagella so motile stage is absent. It varies from unicellular to complex-multicellular algae. Most of them are autotropic except Harveyella which is a colorless parasitic red alga. Harveyella cells show secondary pit connections with other parasitic cells or host. Mostly Harveyella is parasitic over Polysiphonia. 

Chondrus crispus is a red algae which is an Irish moss. The word Iris means "little rock", it is a species of red alga which grows abundantly along rocky parts.

Other options: True moss belongs to class Bryopsida of division Bryophyta. Lichens are symbiotic association of algae with fungi found in moist habitat. Division Bryophyte exist in moist and aquatic environment called as amphibians of plant kingdom.

Green algae have characters similar to higher plants in terms of photosynthetic pigments, cell wall and store food. Green algae are photosynthetic eukaryotes bearing double membrane plastids containing Chl a, Chl b, accesorry pigments. Starch is stored inside the plastid as a reserve food material. Cell wall present is composed of cellulose.

Pyrenoids are sub-cellular micro compartments found in chloroplast of land plants of many algae. Pyrenoids are associated with carbon concentrating mechanism. Their main function is to act as centres of CO$$_2$$ fixation by generating and maintaining a CO$$_2$$ rich environment around RubisCo. A starch sheath is often formed or deposited at the periphery of pyrenoids, even when that starch is synthesised in the cytosol rather than in the chloroplast. Thus, the correct answer is option B.