All Free Biology MCQs with Answers

1151. In term of spore production Selaginella is characterized by________________?

• A. Homosporous
• B. Hetrosporous
• C. Both depending upon the conditions
• D. None of these

Explanation: Selaginella is heterosporous, producing small microspores in microsporangia and larger megaspores in megasporangia. Students often select homosporous because many ferns and some other pteridophytes produce only one type of spore.

1152. Which of the following is an example of the living member of Psilopsida________________?

• A. Rhynia
• B. Psilophyton
• C. Psilotum
• D. Cooksonia

Explanation: Psilotum is a living representative of Psilopsida, the whisk-fern group. Rhynia, Psilophyton and Cooksonia are extinct fossil plants, so choosing one of them confuses historical members with a living example.

1153. Gametophyte of Psilopsida develops a symbiotic association with which of the following______________?

• A. Algae
• B. Bacteria
• C. Protozoa
• D. Fungus

Explanation: The underground gametophyte of Psilopsida lacks chlorophyll and obtains nourishment through a symbiotic association with fungi. The likely distractor is algae, but the standard association involved in nutrient exchange is mycorrhizal fungus.

1154. Ferns are included in__________?

• A. Psilopsida
• B. Lycopsida
• C. Sphenopsida
• D. Pteropsida

Explanation: Ferns are classified under Pteropsida, the group of vascular plants with fronds and spore-producing structures. Psilopsida, Lycopsida and Sphenopsida represent different pteridophyte groups, not true ferns.

1155. Antheridia and archegonia are born on ______________ in bryophytes.

• A. Sporophyte
• B. Gametophyte
• C. Both of these
• D. None of these

Explanation: Antheridia and archegonia are the male and female sex organs of bryophytes, and they develop on the haploid gametophyte generation. The likely mistake is sporophyte, which develops after fertilisation and produces spores rather than gametes.

1156. Which of the following statement about plants is incorrect?

• A. All are eukaryotes
• B. They are multicellular.
• C. Non-motile organisms
• D. They Are heterotrophes

Explanation: Plants are eukaryotic, multicellular and generally non-motile organisms, and most make organic food by photosynthesis, so they are primarily autotrophic. The likely incorrect statement is heterotrophes, because it wrongly describes plants as obtaining their food from other organisms.

1157. Psedudocoelom is character of____________?

• A. Coelenterates
• B. Platyhelminthes
• C. Aschelminthes
• D. Annelids

Explanation: Aschelminthes, including nematodes, are pseudocoelomates because their body cavity is derived from the persistent blastocoel and is not completely lined by mesoderm. Students may choose Platyhelminthes, but flatworms are acoelomates and have no body cavity.

1158. Free living example of Platyhelminthes is____________?

• A. Dugesia
• B. Fasciola
• C. Taenia
• D. None of these

Explanation: Dugesia is a free-living planarian that belongs to Platyhelminthes, whereas Fasciola and Taenia are parasitic flatworms. The common mistake is choosing Fasciola because it is also a well-known platyhelminth, but it lives as a parasite in the bile ducts.

1159. The resolving power of electric microscope is____________?

• A. 0.2 mm
• B. 0.2 nm
• C. 0.2 m
• D. none of these

Explanation: An electron microscope uses electrons with much shorter wavelengths than visible light, giving a resolving power of about 0.2 nm. Students often choose 0.2 mm by confusing the nanometre scale of cell ultrastructure with the much larger millimetre scale.

1160. Which of following system is segmentally arranged in annelids?

• A. Excretory system
• B. Digestive system
• C. Criculatory system
• D. Nervous system

Explanation: Annelid segmentation is reflected in the arrangement of their circulatory vessels and repeated connecting vessels across body segments. Students may choose the digestive system, but the alimentary canal is mainly a continuous tube rather than a series of repeated segments.