NEET Biology Plant Kingdom Important Questions Set 02

These Class 11 NEET Biology important questions on Plant Kingdom give 23 questions with step-by-step answers, arranged as very short, short and long answer types, taken from a model test paper. They help NEET aspirants revise the definitions, structures, differences and key terms of the chapter.

Very Short Answer Type Questions

Question 1. What is meant by a thallus?
Answer: Thallus refers to the plant body which is not differentiated into root, stem and leaves as in algae and lower bryophytes.

Question 2. Name the structure that fixes the brown algae to the substratum.
Answer: Holdfast

Question 3. Name the characteristic red pigment of red algae.
Answer: r-phycoerythrin

Question 4. What happens to the synergids after fertilisation?
Answer: They degenerate.

Question 5. What are gymnosperms?
Answer: Gymnosperms are vascular plants in which the seeds are not enclosed within the fruit wall.

Question 6. What type of sexual reproduction is shown by Volvox?
Answer: Oogamous

Question 7. Name the structure formed by the germination of a spore of a fern.
Answer: Prothallus

Question 8. Name the two main parts of a stamen.
Answer: Filament and anther.

Short Answer Type Questions

Question 9. How does isogamous reproduction differ from anisogamous reproduction?
Answer: In isogamous reproduction, fusion of two gametes either flagellated or non-flagellated but similar in size takes place whereas in anisogamous reproduction fusion of two gametes dissimilar in size takes place.

Question 10. Name the characteristic pigments of brown algae.
Answer: Chlorophyll a & c, carotenoids and xanthophylls (fucoxanthin).

Question 11. How do the gametophytes of bryophytes differ from those of gymnosperms?
Answer: In bryophytes the gametophytes are independent, free-living and form the main plant body whereas in gymnosperms the gametophytes do not have an independent free-living existence. They remain within the sporangia retained on the sporophytes.

Question 12. How does asexual reproduction occur in liverworts?
Answer: Asexual reproduction in liverworts takes place by fragmentation of thalli or by the formation of specialised structures called gemmae. The gemmae become detached from the parent body and germinate to form new individuals.

Question 13. Name three algae that show haplodiplontic life cycle. Name one algae that shows diplontic life cycle.
Answer: Ectocarpus, Polysiphonia, kelps show haplodiplontic life cycle. Fucus shows diplontic life cycle.

Question 14. Write two examples of green algae that are filamentous. What is the common mode of vegetative reproduction in green algae?
Answer: Ulothrix and Spirogyra. In green algae vegetative reproduction usually takes place by fragmentation or formation of different types of spores.

Question 15. What is the ploidy of endosperm in flowering plants and how is it formed?
Answer: Triploid. One of the haploid male gametes fertilises the diploid secondary nucleus forming the triploid endosperm.

Short Answer Type Questions

Question 16. Name the three classes of algae and mention the pigments present in them.

Answer:

Class – Chlorophyceae

Pigments – Chlorophyll a & b

Class – Phaeophyceae

Pigments – Chlorophyll a & c, carotenoids and xanthophylls.

Class – Rhodophyceae

Pigments – Chlorophyll a & d, phycoerythrin.

Question 17. Write the names of any three classes of pteridophytes. Give one example for each.

Answer:

Psilopsida e.g., Psilotum

Lycopsida e.g., Lycopodium

Sphenopsida e.g., Equisetum

Question 18. Mention three economic importance of the first terrestrial plants having vascular tissues.

Answer:

(i) Soil binding : Pteridophytes bind the soil even along hill slopes. The soil is protected from erosion.

(ii) Medicines : An anthelmintic drug is obtained from Dryopteris.

(iii) Ornamentals : Ferns are grown as ornamental plants for their delicate and graceful leaves.

Question 19. What are the two classes of angiosperms? Give an example for each.

Answer:

The two classes are

(i) Dicotyledons : Dicots are flowering plants which are characterised by the presence of two cotyledons in the seed e.g., Pea.

(ii) Monocotyledons : Monocots are flowering plants which are characterised by the presence of a single cotyledon in the seed e.g., Banana.

Question 20. Represent schematically the haplo-diplontic life cycle.
Sporophyte (2n) Zygote (2n) A

Answer:

Syng amy Meiosis

Gametogenesis Haplo-diplontic Spores B (n)

Gametophyte(n)

Haplo-diplontic Life Cycle

Question 21. Describe the type of fertilisation that is unique to plants in which seeds are enclosed by fruits.
Answer: The pollen tube enters the embryo sac and discharge the male gametes present in the pollen grain. One of the male gametes fuses with the egg cell to form zygote. This is known as syngamy. The other male gamete fuses with the diploid secondary nucleus to produce the triploid primary endosperm nucleus (PEN). Thus, double fertilisation occurs, an event unique to angiosperms.

Long Answer Type Questions

Question 22. Describe the important characteristic of archegoniate spermatophytes (any five).
Answer: Gymmosperms are archegoniate spermatophytes
(i) These are the seed-bearing plants, where the ovules are not enclosed in an ovary and hence, the seeds are naked (not enclosed in a fruit).
(ii) Unlike bryophytes and pteridophytes, in gymnosperms the male and female gametophytes do not have an independent free-living existence.
(iii) The plants represent the diploid sporophytic phase in the life cycle.
(iv) They include medium-sized trees or tall trees and shrubs. The Sequoia (Red wood tree) is one of the tallest tree species.
(v) Plant body is differentiated into roots, stem and leaves. The roots are generally tap roots. Roots in some genera have fungal association in the form of mycorrhiza (Pinus), while in some others (Cycas) small specialised roots called coralloid roots are associated with nitrogen-fixing cyanobacteria. Coralloid roots do not possess root hairs and root caps.

Question 23. Represent schematically the life cycle of an angiosperm. Name its life cycle pattern.

Answer:

Anther Microspore Stigma mother cell Filament Microsporangium

Ovary Microspore Megasporangium (ovule)

GAMETOPHYTIC (n) Sporophyte SPOROPHYTIC GENERATION (2n) GENERATION

Microspore (pollen grain) Embryo

Male gametophyte Zygote Egg Gametes

Life Cycle of an angiosperm Diplontic Life Cycle.