Plant Kingdom

The condition where ovules are not enclosed by an ovary wall (i.e., exposed ovules) is a characteristic feature of gymnosperms.

A. Selaginella – a pteridophyte; does not have seeds or ovules
B. Funaria – a bryophyte; no ovules
C. Pinus – a gymnosperm; ovules are naked (not enclosed by ovary)
D. Wolffia – an angiosperm; ovules enclosed within ovary

Correct answer: Option C

• A. Asexual reproduction in Phaeophyceae occurs usually by biflagellate zoospores.
• C. Stored food in Phaeophyceae is in the form of complex carbohydrates, either as mannitol or laminarin.
• D. Major pigments found are chlorophyll a, c, carotenoids, and xanthophyll.
• E. Vegetative cells have a cellulosic wall, usually covered on the outside by a gelatinous coating of algin.

Statement B is incorrect because sexual reproduction in Phaeophyceae can be isogamous, anisogamous, or oogamous, not exclusively oogamous.

A. Gymnosperms: Cedrus, Pinus, Sequoia
→ All three (Cedrus, Pinus, Sequoia) are gymnosperms (conifers).

B. Angiosperms: Wolffia, Eucalyptus, Sequoia
→ Sequoia is a gymnosperm, not an angiosperm.

C. Bryophytes: Polytrichum, Polysiphonia, Sphagnum
→ Polysiphonia is an alga (Rhodophyceae), not a bryophyte.

D. Pteridophytes: Equisetum, Ginkgo, Adiantum
→ Ginkgo is a gymnosperm, not a pteridophyte.

Correct answer: A — Gymnosperms: Cedrus, Pinus, Sequoia

In bryophytes like Marchantia, gemmae are small, green, disc-like structures involved in asexual reproduction. They are produced inside cup-like structures called gemma cups, usually found on the surface of the thallus (plant body). When water (like rain) splashes into the gemma cups, gemmae are dispersed to nearby places. If they land in a suitable environment, each gemma can grow into a new plant that is genetically identical to the parent. Gemmae do not help in nutrient absorption, gaseous exchange, or sexual reproduction. Hence, they play a key role in vegetative (asexual) reproduction in bryophytes.

The correct sequence in the life cycle of bryophytes (like mosses and liverworts), which follows an alternation of generations, is:

1. B — Attachment of gametophyte to substratum
   → The gametophyte (haploid) grows and attaches to the soil or rock.

2. E — Release of antherozoids into water
   → Male gametes (antherozoids) are released and need water to swim to the female part.

3. A — Fusion of antherozoid with egg
   → Fertilization occurs in the archegonium, forming a diploid zygote.

4. D — Formation of sporophyte
   → The zygote develops into a sporophyte (diploid), which remains attached to the gametophyte.

5. C — Reduction division to produce haploid spores
   → The sporophyte undergoes meiosis to form haploid spores for a new generation.

So, the correct order is B, E, A, D, C → Option A.

The life cycle of pteridophytes shows alternation of generations — a diploid sporophyte and a haploid gametophyte stage. The correct sequence is:

1. B. Meiosis in spore mother cells – The diploid sporophyte undergoes meiosis to produce haploid spores.

2. A. Prothallus stage – Spores germinate to form the gametophyte, called the prothallus.

3. D. Formation of archegonia and antheridia – The gametophyte produces male (antheridia) and female (archegonia) sex organs.

4. E. Transfer of antherozoids to archegonia in presence of water – Sperm (antherozoids) swim to the egg using water.

5. C. Fertilisation – Sperm fertilizes the egg, forming a zygote that grows into a new sporophyte.

Thus, the correct order is C: B, A, D, E, C.

Pteridophytes are classified into four distinct classes :

1. Psilopsida (e.g., Psilotum)

2. Lycopsida (e.g., Selaginella, Lycopodium)

3. Sphenopsida (e.g., Equisetum)

4. Pteropsida (e.g., Dryopteris, Pteris, Adiantum).

Thus, Sphenopsida belongs to pteridophytes, making option (D) the correct answer.

• A. Asexual reproduction in Phaeophyceae occurs usually by biflagellate zoospores.
• C. Stored food in Phaeophyceae is in the form of complex carbohydrates, either as mannitol or laminarin.
• D. Major pigments found are chlorophyll a, c, carotenoids, and xanthophyll.
• E. Vegetative cells have a cellulosic wall, usually covered on the outside by a gelatinous coating of algin.

Statement B is incorrect because sexual reproduction in Phaeophyceae can be isogamous, anisogamous, or oogamous, not exclusively oogamous.

Both statements are completely accurate: Statement I is correct: Unlike bryophytes and pteridophytes, in gymnosperms, the male and female gametophytes do not have an independent free-living existence. They remain retained within the sporangia retained on the sporophytes. Statement II is correct: The word 'gymnosperm' literally means 'naked seeds' (gymnos = naked, sperma = seed). The ovules are not enclosed by any ovary wall and remain exposed both before and after fertilization. Thus, option (A) is the correct choice.

A. Gymnosperms: Cedrus, Pinus, Sequoia
→ All three (Cedrus, Pinus, Sequoia) are gymnosperms (conifers).

B. Angiosperms: Wolffia, Eucalyptus, Sequoia
→ Sequoia is a gymnosperm, not an angiosperm.

C. Bryophytes: Polytrichum, Polysiphonia, Sphagnum
→ Polysiphonia is an alga (Rhodophyceae), not a bryophyte.

D. Pteridophytes: Equisetum, Ginkgo, Adiantum
→ Ginkgo is a gymnosperm, not a pteridophyte.

Correct answer: A — Gymnosperms: Cedrus, Pinus, Sequoia

A key feature of gymnosperms is that their seeds are naked, meaning the seeds are not enclosed within fruits. Unlike angiosperms (flowering plants), gymnosperms do not form flowers or fruits. Instead, they produce cones (like in pine trees), and the seeds develop on the surface of cone scales, exposed to the environment.

Option A is incorrect because seeds are present.
Option B is incorrect because gymnosperms do not have flowers.
Option C is incorrect because their seeds are not enclosed in fruits.

So, the correct and defining feature is that gymnosperm seeds are naked.