This set of Marine Biotechnology Multiple Choice Questions & Answers (MCQs) focuses on “Marine Algal Biotechnology – Set 2”.
1. Type II algal cell walls does not include __________
a) intracellular material
b) sheath
c) mucilage
d) lorica
View Answer
Explanation: There are four types of cell walls present in algae depending upon the species and environment. Type II cell walls are characterized by deposition of extracellular material; examples include sheaths, frustules, scales, loricas.
2. Scales only exist in eukaryotic algae.
a) True
b) False
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Explanation: Scales are organic or inorganic surface structures occurring as extracellular matrix in eukaryotic algae such as those belonging to the phylum Heterokontophyta, Haptophyta and Chlorophyta.
3. Scales of which material are present in organisms belonging to Heterokontophta?
a) Calcium carbonate
b) Silica
c) Polysaccharides
d) Glucan
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Explanation: Depending upon the species there are three types of scales that can be present as extracellular deposits. In case of heterokontophyta, scales of silica deposited on a glycoprotein matrix are present.
4. Cell membrane made of amorphous hydrated silica is called __________
a) spine
b) mucilage
c) sheath
d) frustule
View Answer
Explanation: In the members of Bacillariophyceae (Heterokontophyta), an ornate cell membrane called the frustule is present. It is composed of amorphous hydrated silica displaying intricate designs unique to each species.
5. The correct sequence of diatom type in the following figure __________
a) centric; pennate; centric; pennate
b) centric; centric; pennate; pennate
c) pennate; pennate; centric; centric
d) pennate; centric; pennate; centric
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Explanation: Depending upon the morphology, there are two types of diatoms namely centric and pennate. In centric diatoms the symmetry is radial the structure of valve arranged in reference to one or more points, as in first and third diagram; in pennate diatoms the symmetry is either bilateral or about one axis.
6. The lateral slit alongside sternum of a diatom is termed ___________
a) striae
b) cingulum
c) raphe
d) aerotope
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Explanation: Raphe is the lateral slit alongside sternum of a diatom that maybe separated by a central nodule (a silica bridge). Depending upon the presence or absence of a raphe, pennate diatoms are subdivided into raphid and araphid.
7. What is the major function of a raphe?
a) Motility
b) Nutrient uptake
c) Maintain pH
d) Maintain temperature
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Explanation: The major function of a raphe (a slit) is motility, a diatom moves when the raphe is adjacent to a substratum to which the cell adheres. A secretion of polysaccharide is made through the raphe slits, believed to be responsible for motion.
8. A cell wall is present in eukaryotic algae.
a) True
b) False
View Answer
Explanation: A cell wall is a rigid protective cover a cell that acts as a protective agent. All eukaryotic and prokaryotic algae possess a cell wall, the composition however can vary depending upon the genera.
9. Alginic acid is a constituent of cell walls of some species in the phylum ________
a) Cyanophyta
b) Haptophyta
c) Rhodophyta
d) Heterokontophyta
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Explanation: Alginic acid is a constituent of cell walls of Phaeophyceae belonging to the phylum Heterokontophyta. The salts of alginic acid have emulsifying and stabilizing properties and hence it is commercially valuable.
10. Which is a vase-shaped structure?
a) Flagella
b) Mucilage
c) Lorica
d) Spine
View Answer
Explanation: Loricas are vase-shaped structures with wide apical openings through which flagella emerge. These are present in some members of Chrysophyceae (Heterokontophyta) such as Dinobryon.
Sanfoundry Global Education & Learning Series – Marine Biotechnology.
To practice all areas of Marine Biotechnology, here is complete set of 1000+ Multiple Choice Questions and Answers.