Free Biodiversity and Variety of Life MCQs with Answers

2001. Plants which produce characteristic pneumat­ophores and show vivipary belong to:

• A. Halophytes
• B. Psammophytes
• C. Hydrophytes
• D. Mesophytes

Explanation: The presence of pneumatophores, i.e., small negatively geotropic vertical roots and vivipary or seed germination while attached to a plant are adaptations of halophytes, i.e., plants growing in saline habitat.

2002. All of the following are the characteristics of bryophytes EXCEPT that they have:

• A. Same types of spores
• B. Multicellular embryo
• C. Dominant sporophyte
• D. Rhizoids to absorb water

Explanation: Bryophytes have same spores, multicellular embryo and rhizoids. Bryophytes have a dominant gametophyte stage, not a sporophyte stage, that is why this characteristic does not apply to them. So, option C is correct option.

2003. The growing point of the new sporophyte in the shown fern prothallus is labelled as:

• A. Option A
• B. Option B
• C. Option C
• D. Option D

Explanation: In the life cycle of ferns, the prothallus is the gametophyte stage, which is small and heart-shaped. The new sporophyte begins to grow from the fertilized egg located on the prothallus. The 'growing point' is where this new sporophyte develops, typically labeled as 'A' in diagrams.

2004. Sphenopsida are also called as arthrophytes because their plant body:

• A. Has bushy appearance
• B. Has sporangia on sporangiophores
• C. Has large number of joints in stem
• D. Stores granules of silica within the cells

Explanation: The term 'arthrophytes' is used to describe plants in the Sphenopsida class due to their distinctive jointed stems. This structure is reminiscent of the segmented limbs of arthropods.The correct option is C: Has large number of joints in stem.

2005. In the female gametophyte of an angiosperm, the ploidy of synergies, antipodal cells, and polar nuclei is:

• A. Haploid, Haploid, Haploid
• B. Haploid, Haploid, Diploid
• C. Diploid, Diploid, Diploid
• D. Diploid, Diploid, Haploid

Explanation: In angiosperms, the female gametophyte is called the embryo sac. It typically consists of seven cells: three antipodal cells, two synergids, one egg cell, and a polar nuclei. The synergids, antipodal cells, and the egg cell are haploid (n) because they arise from the meiotic division of the megaspore mother cell. The polar nuclei, however, is diploid (2n) because it contains two haploid nuclei, which later fuse with a sperm cell during fertilization to form the triploid endosperm. Therefore, the correct ploidy levels are haploid for synergids and antipodal cells and diploid for the polar nuclei.

2006. Potatoes and tomatoes are economically important members of family:

• A. Rosaceae
• B. Fabaceae
• C. Solanaceae
• D. Mimosaceae

Explanation: The Solanaceae family, also known as the nightshade family, encompasses a variety of economically significant crops, including potatoes, tomatoes, eggplants, and peppers. Each option represents a different plant family, but only Solanaceae includes both potatoes and tomatoes.

2007. The option that CORRECTLY represents the characteristics of the sporophyte and gametophyte generations of a gymnosperm is:

• A. Independent and dominant, less conspicuous and dependent
• B. Less conspicuous and dependent, independent and dominant
• C. Dependent and dominant, more conspicuous and independent
• D. More conspicuous and independent, dependent and dominant

Explanation: In gymnosperms, the life cycle includes two distinct generations: the sporophyte and the gametophyte. The sporophyte generation is the most visible and dominant phase, characterized by being independent and capable of producing spores. So option A is correct.

2008. The given diagram shows two gametophytes of Marchantia plant.The structure that bears antheridia is labelled as:

• A. Option A
• B. Option B
• C. Option C
• D. Option D

Explanation: In Marchantia, the gametophyte is the dominant phase of the life cycle, exhibiting structures known as antheridiophores and archegoniophores. Antheridia, the male reproductive organs, are borne on antheridiophores. In the diagram, the structure labeled D is identified as the antheridiophore, hence it bears the antheridia.so option D is the correct option.

2009. The floral diagram that illustrates an epipetalous androecium is:

• A. Option A
• B. Option B
• C. Option C
• D. Option D

Explanation: In a floral diagram representing an epipetalous androecium, the stamens (androecium) are attached to the petals (corolla). This attachment is a key feature that helps in identifying an epipetalous condition. So, option A correctly depicts this arrangement, with the stamens visibly attached to the petals.

2010. In the given diagram life cycle of moss plant ,the stage at which meiosis occurs is:

• A. Option A
• B. Option B
• C. Option C
• D. Option D

Explanation: The correct answer is D: (Sporangium). In the life cycle of a moss plant, meiosis occurs in the sporangium. The sporangium is a structure on the sporophyte where meiosis takes place, leading to the formation of haploid spores. These spores eventually germinate and develop into the protonema and subsequently the gametophyte.