74. Which genus is a sac fungus?
[NEET UG Gujarati Paper, 2017]
(A) Agaricus
(B) Neurospora
(C) Mucor
(D) Albugo
Answer: (B) Neurospora
Explanation: Neurospora is an ascomycete whose sexual spores develop in asci. Agaricus produces basidiospores and belongs to Basidiomycetes. Mucor and Albugo were classed with lower fungi in older textbooks.
73. Which is a flagellated protozoan?
[NEET UG Gujarati Paper, 2017]
(A) Paramecium
(B) Trypanosoma
(C) Entamoeba
(D) Plasmodium
Answer: (B) Trypanosoma
Explanation: Trypanosoma is a flagellated parasitic protist transmitted by insect vectors. Paramecium is a ciliate, Entamoeba uses pseudopodia, and Plasmodium is traditionally regarded as a sporozoan.
72. The protein covering of a virus is termed:
[NEET UG Gujarati Paper, 2017]
(A) Core
(B) Capsid
(C) Trichome
(D) Capsule
Answer: (B) Capsid
Explanation: The viral capsid is built from protein subunits called capsomeres and protects the nucleic acid. A bacterial capsule is an external protective layer, while a trichome refers to certain cellular hairs or filaments.
71. Which of these animals is a mollusc?
[RRB NTPC, 18 April 2016]
(A) Snail
(B) Starfish
(C) Earthworm
(D) Cockroach
Answer: (A) Snail
Explanation: Snails possess the soft body, mantle and muscular foot typical of Mollusca. Starfish belong to Echinodermata, earthworms to Annelida and cockroaches to Arthropoda, demonstrating differences between the major invertebrate phyla.
70. Which assertion is incorrect regarding true fungi?
[NEET UG Phase II, 2016]
(A) They are eukaryotes
(B) Every species has walls made exclusively from cellulose
(C) They are heterotrophs
(D) Both unicellular and multicellular forms occur
Answer: (B) Every species has walls made exclusively from cellulose
Explanation: True fungal walls normally contain chitin and glucans, not purely cellulose. Fungi are eukaryotic absorptive heterotrophs, comprising yeasts and filamentous species. Their wall composition helps distinguish them from plants.
69. Methanogens are members of which group?
[NEET UG Phase II, 2016]
(A) Eubacteria
(B) Archaebacteria
(C) Dinoflagellates
(D) Slime moulds
Answer: (B) Archaebacteria
Explanation: Methanogens are methane-producing archaea occurring in anaerobic habitats such as wetlands, sewage digesters and ruminant stomachs. Their distinctive biochemistry and cell envelopes distinguish them from eubacteria.
68. Choose the false statement concerning diatoms.
[NEET UG Phase II, 2016]
(A) Their silica-based cell walls disintegrate very easily
(B) Their skeletal remains form diatomaceous earth
(C) They contribute greatly to marine photosynthesis
(D) Many live as microscopic plankton
Answer: (A) Their silica-based cell walls disintegrate very easily
Explanation: Diatom frustules contain silica and resist decay remarkably well. Huge accumulations of these shells form diatomaceous earth. Diatoms are floating photosynthetic protists and constitute an important component of marine primary productivity.
67. Which property attributed to viroids is incorrect?
[NEET UG Phase I, 2016]
(A) They have no protein coat
(B) They are smaller than most viruses
(C) They cause infections
(D) They contain high-molecular-weight RNA
Answer: (D) They contain high-molecular-weight RNA
Explanation: Viroids are small, low-molecular-weight RNA agents capable of infecting plants. They possess neither a capsid nor DNA. Their simple structure contrasts sharply with the more elaborate particles formed by viruses.
66. Which taxonomic hierarchy is correctly written from highest to lowest?
[UPSC CAPF Assistant Commandant, 26 June 2016]
(A) Kingdom, Phylum, Order, Genus, Family, Class, Species
(B) Kingdom, Order, Class, Phylum, Family, Genus, Species
(C) Kingdom, Class, Order, Phylum, Family, Species, Genus
(D) Kingdom, Phylum, Class, Order, Family, Genus, Species
Answer: (D) Kingdom, Phylum, Class, Order, Family, Genus, Species
Explanation: The standard progression from broadest to narrowest is kingdom, phylum, class, order, family, genus and species. Related species form genera and related genera form families. Scientific classification employs this nested hierarchy.
65. Chrysophytes, dinoflagellates, euglenoids and slime moulds belong to which traditional kingdom?
[NEET UG Phase I, 2016]
(A) Monera
(B) Protista
(C) Fungi
(D) Animalia
Answer: (B) Protista
Explanation: Whittaker grouped many eukaryotic microorganisms within Protista. Chrysophytes, euglenoids, dinoflagellates and slime moulds show considerable ecological and nutritional diversity but differ from prokaryotic Monera.
