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Botany Past Paper MCQs
Botany 2025 MCQs
1 / 20
Which type of pollination involves the transfer of pollen by wind?
Anemophily is wind pollination (e.g., grasses). Entomophily (C) is by insects, hydrophily (A) by water.
2 / 20
The tallest living plant species belongs to the group of:
Gymnosperms include Sequoia sempervirens (redwoods), the tallest trees. Angiosperms (B) are flowering plants.
3 / 20
In which part of the plant does the Calvin cycle occur?
The Calvin cycle (dark reaction) fixes CO₂ in the stroma. Thylakoids (B) host light reactions.
4 / 20
Which scientist is known for developing the concept of genetic drift?
Sewall Wright pioneered genetic drift. Mendel (A) studied inheritance, and Darwin (C) proposed natural selection.
5 / 20
Which of the following is the dominant generation in the life cycle of Pteridophytes?
Unlike bryophytes (gametophyte-dominant), pteridophytes (e.g., ferns) have a sporophyte (2n) as the dominant, independent phase.
6 / 20
The cell wall of fungi is primarily composed of:
Fungi have cell walls made of chitin, a tough polysaccharide also found in insect exoskeletons. Plants use cellulose (A), pectin (C) is in plant cell walls, and lignin (D) reinforces wood.
7 / 20
In the process of transcription, the RNA polymerase binds to which region of the gene to initiate synthesis?
The promoter is the binding site for RNA polymerase. Exons (B) are coding regions, and introns (C) are non-coding.
8 / 20
Plants that grow under direct sunlight are known as:
Heliophytes (sun plants) thrive in sunlight. Sciophytes (B) prefer shade, and "psamophytes" (C) are sandy-soil plants (e.g., dune grasses)..
9 / 20
What is the characteristic feature of the Fabaceae family?
Fabaceae (legumes) have a butterfly-shaped papilionaceous corolla. Composite flowers (A) are in Asteraceae.
10 / 20
Which of the following is NOT a characteristic of algae?
Algae range from microscopic (e.g., Chlorella) to giant kelp (macroscopic). They are autotrophic (A), can be multicellular (B), and lack true roots (C).
11 / 20
Which organelle is involved in modifying, sorting, and packaging proteins for secretion?
The Golgi apparatus processes proteins from the ER (A). Lysosomes (C) digest waste, and peroxisomes (D) break down toxins.
12 / 20
The study of heritable changes in gene expression without alteration in the underlying DNA sequence is called:
Epigenetics studies modifications like DNA methylation that affect gene activity.
13 / 20
A cross between an individual with an unknown genotype and a homozygous recessive individual is called a:
A test cross reveals the unknown genotype by crossing with recessive (e.g., Tt × tt). Backcross (A) involves a parental generation.
14 / 20
Which element is an essential micronutrient for nitrogen fixation in legumes?
Molybdenum is a cofactor for nitrogenase, the enzyme that fixes atmospheric nitrogen (N₂) in root nodules of legumes.
15 / 20
Which group of organisms is known for having chloroplasts in every cell?
Algae are photosynthetic and contain chloroplasts. Fungi (A) lack chloroplasts, and bryophytes (C) have them only in green tissues.
16 / 20
In dicot plants, the first leaf - like structure that emerges from the seed is called:
The cotyledon (seed leaf) provides nutrients. The hypocotyl (A) is the stem below it, and the radicle (D) is the embryonic root. (Note: "Epitaxy" in option C is a typo; "epicotyl" would refer to the shoot above cotyledons.)
17 / 20
In angiosperms, how many nuclei are present in a mature embryo sac?
The megagametophyte (embryo sac) has 8 nuclei: 1 egg, 2 synergids, 3 antipodals, and 2 polar nuclei.
18 / 20
The phase of mitosis in which chromosomes align at the cell's equator is called:
In metaphase, chromosomes line up at the metaphase plate. Anaphase (A) separates them, and telophase (B) divides the cell.
19 / 20
The process of transcription involves the synthesis of:
Transcription copies DNA into RNA. Translation (B) makes proteins from RNA.
20 / 20
What is the ploidy level of the endosperm in angiosperms?
Endosperm forms when two polar nuclei (2n) fuse with a sperm (n), resulting in 3n.
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