Angiosperms

Step 1: Understanding Scientific Names and Common Names
- Colchicum autumnale → Meadow saffron (IV)
- Dracaena angustifolia → Red dragon (III)
- Yucca gloriosa → Spanish dagger (I)
- Withania somnifera → Ashwagandha (II)
Step 2: Matching Correctly
Correct matching: A-IV, B-III, C-I, D-II.

Step 1: Understanding the Floral Formula of Solanum nigrum
Solanum nigrum belongs to the Solanaceae family. Its floral characteristics are:
- Bracteate (Br)
- Ebracteolate (Ebr)
- Actinomorphic (Radial symmetry, )
- Calyx (K) with 5 fused sepals - Corolla (C) with 5 fused petals
- Androecium (A) with 5 epipetalous stamens
- Gynoecium (G) with a bicarpellary ovary (2 fused carpels)
Step 2: Identifying the Correct Answer
The correct floral formula is:

Step 1: Define Flower Types:

• Cleistogamous flowers: These flowers do not open at all. Their reproductive organs are enclosed.
• Chasmogamous flowers: These are open flowers with exposed anthers and stigma.

Step 2: Analyze Pollination Types:
Since Cleistogamous flowers never open, cross-pollination (xenogamy) or pollination from another flower on the same plant (geitonogamy) is physically impossible. The pollen from the anthers must land on the stigma of the \same flower. Therefore, they invariably exhibit autogamy (self-pollination).
Step 3: Analyze Other Options:
(B) Chasmogamous flowers can exhibit autogamy, geitonogamy, or xenogamy depending on the plant and pollinators.
(C) Cleistogamous flowers cannot exhibit geitonogamy because they are closed.
(D) Chasmogamous flowers \can exhibit autogamy (e.g., if pollen falls on the stigma of the same flower).
Step 4: Final Answer:
The correct statement is (A).

Step 1: Concept of Seed Formation:
One seed is formed from the fertilization of one female gamete (egg cell) by one male gamete.
Step 2: Calculating Meiosis for Female Part (Megasporogenesis):
1 Megaspore Mother Cell (MMC) undergoes 1 Meiotic division to form 4 megaspores. Usually, only 1 becomes functional and forms the embryo sac. For 1600 seeds Meiotic divisions.
Step 3: Calculating Meiosis for Male Part (Microsporogenesis):
1 Pollen Mother Cell (PMC) undergoes 1 Meiotic division to form 4 Pollen grains (Microspores). For 1600 seeds (requiring 1600 pollens):
Step 4: Total Meiotic Divisions:

Step 5: General Formula:
Total Meiosis ( ) for seeds:

Step 1: Understanding RNA Interference (RNAi):
RNA interference (RNAi) is a biological process in which RNA molecules inhibit gene expression or translation. It is a natural defense mechanism in eukaryotic organisms.
Step 2: Mechanism:
RNAi involves the silencing of a specific mRNA molecule. This silencing is achieved through the formation of a double-stranded RNA (dsRNA) molecule. The complementary RNA strand binds to the target mRNA, preventing its translation into protein. This process is effectively "silencing" the gene.
Step 3: Evaluating Options:
(A) Synthesis of cDNA uses reverse transcriptase, which is not the primary mechanism of RNAi.
(B) Silencing of specific mRNA due to complementary RNA correctly describes the core mechanism.
(C) Interference of RNA in DNA synthesis is incorrect.
(D) Synthesis of mRNA from DNA is transcription, not RNAi.
Step 4: Final Answer:
The correct option is (B).

1. Each basidium undergoes one nuclear fusion (karyogamy) to form a diploid nucleus — so number of nuclear fusions equals number of basidia. For 60 basidia: nuclear fusions = 60.
2. Each basidium then undergoes one meiotic division (meiosis I and II sequence considered as one meiotic event) producing four haploid nuclei which form four basidiospores. Thus meiotic divisions per basidium = 1, total meiotic divisions = 60.
3. Each basidium produces 4 basidiospores, so total basidiospores = 60 4 = 240.
4. Therefore the counts are 60 nuclear fusions; 60 meiotic divisions; 240 basidiospores — (1) 60; 60 & 240.

The hilum is a small mark or scar on the seed coat that represents the point of attachment of the seed to the ovary or funiculus during development. The assertion (A) is true. The reason (R) correctly explains the formation of the hilum, because the seed receives nutrients through the funiculus during development, and after detachment, the scar remains. Hence, both statements are true and (R) is the correct explanation.

Cohorts in flowers indicate the number of whorls in a flower. Thalamiflorae have numerous free floral parts (highest number of coharts), followed by Disciflorae, Heteromerae, and Calyciflorae (least number). Therefore, the descending order based on number of coharts is option (1).

1. In the bean family (Leguminosae/Fabaceae), the ovules are typically anatropous or campylotropous — the body of the ovule is bent (I is true).
2. "Ovule is placed at right angles to the funiculus" (II) corresponds to orthotropous/hemianatropous conditions; legumes commonly show anatropous or campylotropous ovules rather than strictly right-angled placement, so II is not a general characteristic.
3. The embryo sac may be slightly curved in such ovules (III is accepted as true in many leguminous ovules), and the micropyle often faces or comes towards the funiculus due to the curvature (IV true).
4. Therefore I, III and IV correctly describe typical ovule characters related to the bean family. Hence the correct answer is (3) I, III & IV.

In pitcher plants, the lamina forms the pitcher (A-IV), the upper part of petiole forms a tendril (C-II), the lower part of petiole becomes a phyllode (B-III), and the leaf tip forms a lid (D-I). These modifications help in insect trapping, photosynthesis, and protection. Thus, option (4) correctly represents the functional leaf modifications.

1. Row I (Pisum): Pisum (pea) has diadelphous stamens (a typical papilionaceous flower condition) — that part of the pair (List-2) is correct. However, "Two carpels" (List-3) is incorrect for Pisum: pea has a single carpel (mono carpellary, forming a single pod). So the Pisum pair is wrong (I is wrong).
2. Row II (Arachis): Arachis (peanut) belongs to Papilionoideae and typical papilionaceous flowers have diadelphous stamens (9+1), not monadelphous (all fused into one). Thus "Monodelphous stamens" is an incorrect descriptor for Arachis — so II is also wrong. The fruit being a dehiscent pod is correct.
3. Row III (Nicotiana): Nicotiana often shows cymose to panicle type inflorescences and the fruit is indeed a capsule — this row is typically correct.
4. Row IV (Ruscus): Ruscus has unisexual flowers and cladophylls (flattened stems) — this is correct.
5. Therefore the wrong pairs are I (Pisum) and II (Arachis). Hence the correct option is (2) I & II.