Free Biodiversity and Variety of Life MCQs with Answers

1741. Bryophytes can be separated from algae, because they

• A. Possess archegonia
• B. Contain chloroplast
• C. Are thalloid forms
• D. Have no conducting tissue

Explanation: Bryophytes, such as mosses and liverworts, possess specialized structures called archegonia, which are involved in the fertilization process. These archegonia are a key characteristic that distinguishes bryophytes from algae and plays a crucial role in their reproductive cycle.

1742. Multicellular branched rhizoids and leafy gametophytes are the characteristics of

• A. Some bryophytes
• B. Pteridophytes
• C. All bryophytes
• D. Gymnosperms

Explanation: Multicellular branched rhizoids and leafy gametophytes are characteristics of some bryophytes. Bryophytes include mosses, liverworts, and hornworts, and while not all bryophytes have these features, many mosses, for example, exhibit multicellular branched rhizoids for anchorage and absorption and have leafy gametophytes, which are the dominant and photosynthetic phase of their life cycle. Other options are explained below: Pteridophytes: Pteridophytes, which include ferns, horsetails, and whisk ferns, do not typically have multicellular branched rhizoids. Instead, they have true roots and vascular tissues that transport water and nutrients. All Bryophytes: While multicellular branched rhizoids are found in some bryophytes, not all bryophytes necessarily have them. The presence of multicellular branched rhizoids varies among different species of bryophytes. Gymnosperms: Gymnosperms are a group of seed-producing plants like conifers, cycads, and ginkgoes. They have vascular tissues and a sporophyte-dominant life cycle, so they do not have multicellular branched rhizoids or leafy gametophytes like bryophytes.

1743. The smallest plant family 'Gymnosperm' has how many species?

• A. 640
• B. 300
• C. 1000
• D. 900

Explanation: (d) : Gymnosperms originated about 200 million years ago and were dominant species at that time. However most ofthe members have become extinct now and only few living forms are known today. There are around 900 living species of this group.

1744. Brown algae is characterised by the presence of

• A. Fucoxanthin
• B. Haematochrome
• C. Phycocyanin
• D. Phycoerythrin

Explanation: a. Brown algae are the members of the Class Phaeophyceae. Their chromatopores are ellipsoidal or discoid. They contain chlorophyll a, chl c, b­ and c­carotenes and xanthophyll pigments (e.g., lutein, flavoxanthin, violaxanthin). They alsocontain large amount of a brown pigment - fucoxanthin which masks the green colour of chlorophyll pigment. This gives characteristic brown colour to these plants, hence the name brown algae. b. Haematochrome is not a characteristic pigment of brown algae. c. and d. Phycocyanin and Phycoerythrin are pigments typically found in some types of red algae, not brown algae.

1745. Which of the following plant kingdom is called 'amphibians'?

• A. Pteridophyta
• B. Thallophyta
• C. Tracheophyta
• D. Bryophyta

Explanation: d. Bryophyta is indeed referred to as the "amphibians" of the plant kingdom because they are often found in damp or aquatic environments and have a life cycle that depends on water for reproduction.( correct option) Other options are explained below: Pteridophyta: This plant kingdom includes ferns and their relatives. While they also need water for fertilization, they are not referred to as "amphibians" like bryophytes because they have more advanced vascular tissues and larger, more complex structures. Thallophyta: This group includes algae and other simple, non-vascular plants. They lack the specialized tissues seen in bryophytes and do not have the same amphibian characteristics. Tracheophyta: This is the vascular plant group, which includes ferns, gymnosperms, and angiosperms (flowering plants). They have well-developed vascular tissues for efficient water and nutrient transport and are not called "amphibians."

1746. Gymnospermic leaf carries 16 chromosomes. The number of chromosomes in its endosperm will be

• A. 12
• B. 8
• C. 16
• D. 24

Explanation: In gymnosperms, the endosperm is typically haploid, and its chromosome number is reduced. In this case, if the gymnospermic leaf carries 16 chromosomes, the endosperm can have 8 chromosomes.

1747. The plant body of moss (Funaria) is

• A. Completely sporophyte
• B. Predominantly gametophyte with sporophyte
• C. Completely gametophyte
• D. Predominantly sporophyte with gametophyte

Explanation: b. Funaria is known as common moss or green moss. The plant body is foliose that consists of stem axis which bears many leaves and instead of roots, rhizoids are present. It is gametophytic (n) and independent. It bears antheridia and archegonia on the same plant but on different branches. After fertilization, the zygote (2n) divides to form the sporophyte which consists of foot, seta, and capsule. The basal foot is embedded in the apex of female branch. It absorbs nutrients and provides support for the sporophyte. Inside the capsule, haploid spores are produced as a result of meiosis. Thus again the gametophytic phase starts. So the gametophytic phase is the dominant phase of the life cycle of Funaria. Hence,The correct answer is: Predominantly gametophyte with sporophyte. Funaria, a moss, has a predominantly gametophyte-dominant life cycle with a small sporophyte. The gametophyte is the dominant, photosynthetic phase of the moss life cycle. Other options are explained below: a. Completely sporophyte: This is not accurate for mosses like Funaria. While the sporophyte stage is present in the life cycle, it is not the dominant or persistent phase. c. Completely gametophyte: This is not accurate either. While the gametophyte is the dominant phase, there is also a sporophyte stage in the life cycle. d. Predominantly sporophyte with gametophyte: This is not accurate for mosses. The sporophyte is not the predominant phase, but rather a smaller and dependent structure in the life cycle.

1748. A well-developed archegonium with neck consisting of 4­6 rows and neck canal cells characterises

• A. Gymnosperms and flowering plants
• B. Pteridophytes and gymnosperms
• C. Gymnosperms only
• D. Bryophytes and pteridophytes.

Explanation: (d) : Bryophytes and pteridophytes both have alternation of generation. The gametophytic phase is dominant in bryophytes whereas in pteridophytes it is short lived. Sex organs are embedded is some members of bryophytes and pteridophytes. Sperms are flagellate and so water is required for fertilization. Sterile jacket is present around the sex organs for protection. Archegoniumappeared for the first time in bryophytes in plant kingdom. It is a flask shaped structure. It has swollen basal portion called venter and upper elongated neck. The venter has egg cell and venter canal cell. There are 4­6 vertical rows of neck cells enclosing neck canal cells in bryophytes. The archegonia have short neck made of four rows of vertically elongated cells that encloses four neck canal cells in pteridophytes.

1749. Which one is the most advanced from evolutionary view point?

• A. Selaginella
• B. Funaria
• C. Chlamydomonas
• D. Pinus

Explanation: From an evolutionary viewpoint, Pinus is considered the most advanced among the options provided. Pinus is a gymnosperm, which represents a more advanced stage of plant evolution compared to other options:Selaginella: Selaginella is a type of pteridophyte, specifically a club moss. While it is more advanced than bryophytes like Funaria, it is still a primitive vascular plant.Funaria: Funaria is a bryophyte, representing a more primitive stage of plant evolution. Bryophytes are non-vascular plants and are considered some of the earliest land plants.Chlamydomonas: Chlamydomonas is a unicellular green alga. It is a member of the Chlorophyta, a group of green algae. Algae are simpler, aquatic organisms in the plant kingdom.Pinus: Pinus is a gymnosperm, which is a more advanced group of seed-producing, vascular plants. Gymnosperms are considered more evolutionarily advanced than bryophytes and some other primitive plants.So, Pinus is the most advanced from an evolutionary perspective in the given options.

1750. Pteridophytes differ from bryophytes and thallophytes in having

• A. Vascular tissues
• B. Motile antherozoids
• C. Archegonia
• D. Alternation of generations

Explanation: a. Vascular Tissues: Pteridophytes are the first group of land plants that possess well-developed vascular tissues, including xylem and phloem. These vascular tissues allow for the efficient transport of water, nutrients, and organic compounds within the plant. b. Motile Antherozoids: Pteridophytes, like bryophytes, have motile antherozoids (sperm cells) for sexual reproduction. Thallophytes typically do not have antherozoids. c. Archegonia: Pteridophytes, like bryophytes, have archegonia, which are structures that produce and protect the eggs during the process of fertilization. Thallophytes may or may not have archegonia. d. Alternation of Generations: Pteridophytes, like bryophytes, exhibit alternation of generations, which involves a multicellular, dependent sporophyte generation and a multicellular, independent gametophyte generation. Thallophytes do not always exhibit this alternation of generations. So, while pteridophytes share some characteristics with bryophytes and thallophytes, they are distinguished by the presence of vascular tissues, archegonia, and an alternation of generations in their life cycle.