NEET Biology Reproduction in Organisms Important Questions Set 01

These Class 12 NEET Biology important questions on Reproduction in Organisms give 45 questions with step-by-step answers, arranged as very short, short and long answer types, as asked in school and board examinations. They help NEET aspirants revise the definitions, structures, differences and key terms of the chapter.

Very Short Answer Type Questions

Question 1. Mention the name of two groups where asexual reproduction is very common by cell division.
Answer: Monerans, Protists

Question 2. Mention the type of bud and its position involved in vegetative propagation in Bryophyllum.
Answer: Adventitious bud, present at margins of leaf in notches.

Question 3. Amongst the three phases of the life cycle of organisms _______ can be of variable durations in different organisms.
Answer: Vegetative, reproductive phase.

Question 4. Name the specialised branches over which and gametes are produced in Marchantia.
Answer: – Antheridiophore – Archegoniophore

Question 5. What is cell differentiation?
Answer: Cell differentiation helps groups of cells to undergo certain modifications to form specialised tissues and organs for an organism.

Question 6. Mention the name of vegetative propagule through which Dahlia is cultivated.
Answer: Dahlia is cultivated through roots.

Question 7. Does formation of zygote and embryo occurs in all the sexually reproducing organisms?
Answer: No, only zygote formation occurs in all the sexually producing organisms. In lower plants like algae, embryo formation is absent.

Question 8. Give an example where transfer of pollen grains occurs to the stigma of same plant.
Answer: Pea

Question 9. "Asexual reproduction is exhibited only by lower plants". This statement is true or false.
Answer: False, it also shown by higher plants. The type of asexual reproduction shown by higher plants is vegetative reproduction.

Question 10. Staminate and pistillate flowers produce the ______ and ______ gametes respectively.
Answer: Male, female

Short Answer Type Questions

Question 11. Name the biological process which ensures continuity of species generation after generation. Mention its two broad categories.
Answer: Reproduction is a biological process in which an organism gives rise to young ones similar to itself. It is divided into two main types i.e., asexual and sexual.

Question 12. Which part of the given organism is used for vegetative propagation? Why this plant was introduced in India?
Answer: Part used for vegetative reproduction is offset. This plant was introduced in India because of the beautiful flowers and shape of leaves.

Question 13. Which part of potato tuber and rhizome of ginger has the ability to form new plantlets?
Answer: Node present on these modified stems posses buds which can form new plantlets.

Question 14. Why Strobilanthus kunthiana is called neelakuranji?
Answer: It produces blue colour flowers once in 12 years. Moreover it shows mass/gregarious flowering which make large tracks of hilly areas in Kerala, Karnataka and Tamil Nadu into blue stretches due to which it is known as neelakuranji.

Question 15. Fill the vacant spaces in the below given flow chart w.r.t. events in sexual reproduction.
A
Vital link - B
Embryogenesis
C
Answer: (A) – Fertilisation (B) – Zygote (C) – New individual

Question 16. Explain sexuality in cucurbits.
Answer: Cucurbits are monoecious i.e., they possess unisexual staminate and pistillate flowers on the same plant body.

Question 17. What is the fate of zygote in plants showing haplontic life cycle?
Answer: In haplontic life cycle all the phases present are haploid except zygote. Diploid zygote work as meiocyte and after meiosis if forms haploid spores which can give rise to new individuals.

Question 18. How gametes are transferred in bryophytes and pteridophytes?
Answer: In these groups flagellated male gametes are transferred through water agency.

Question 19. What is ploidy of gamete and meiocyte? Mention the number of chromosomes in meiocyte of rice and maize.
Answer: Gamete (n), Meiocyte (2n) Rice – Meiocyte – 24 Maize – Meiocyte – 20

Question 20. What does S and P represent in below diagram?
S P
Labelled structures are formed at which stage of sexual reproduction?
Answer: S = Seed, P = Pericarp These structures are formed as a result of post-fertilisation event. Ovule ⎯→ Seed Ovary wall ⎯→ Pericarp

Question 21. Explain embryogenesis. Mention two main changes which occur in zygote during embryogenesis.
Answer: The process of development of embryo from zygote is called embryogenesis. Zygote undergoes cell division (mitosis) and cell differentiation.

Question 22. Bryophytes, Pteridophytes, Algae, Fungi, Gymnosperms, Angiosperms
From the box given above, choose the groups in which zygote develops a thick resistant wall.
Answer: Algae, Fungi. It is resistant to desiccation and damage, which ensure survival of organisms during unfavourable condition.

Question 23. Mention the carrier/medium of male gamete in the following groups.
a. Algae
b. Bryophytes
c. Gymnosperms
d. Angiosperms
Answer: a. Water
b. Water
c. Pollen
d. Pollen

Question 24. Write appropriate answers for the life cycle of an alga having haploid body.
(a) Type of division involved in forming gamete.
(b) Ploidy of zygote and gamete.
Answer: (a) Mitosis
(b) Zygote – 2n, gamete – n

Question 25. (a) Mention three events involved in sexual reproduction.
(b) Which event is involved in formation of vital link between two generations?
Answer: (a) Pre-fertilisation, fertilisation, post-fertilisation
(b) Fertilisation – Zygote

Question 26. Mention name of plants and their fruiting behaviour which can flower
(a) After 50–100 years
(b) Once in 12 years
Answer: (a) 50 - 100 years – Bamboo, monocarpic plant
(b) Once in 12 years – Strobilanthus kunthiana, perennial plant

Question 27. Amongst two modes of reproduction which one is most common one and which one starts before onset of unfavourable conditions in algae and fungi?
Answer: Most common amongst two modes of reproduction is asexual one. During unfavourable condition there is shift to sexual one.

Question 28. Mention name of four vegetative propagules with one example each.
Answer: (a) Rhizome – Ginger
(b) Offset – Eichhornia
(c) Tuber – Potato
(d) Runner – Grasses

Question 29. (a) Mention two groups where special asexual reproductive structures are formed.
(b) Write names of two such structures with examples.
Answer: (a) Kingdom fungi and simple plants such as algae.
(b) Conidia – Penicillium (fungi) Zoospores – Chlamydomonas (algae)

Question 30. Give life span of
(a) Banana tree
(b) Rice plant
(c) Rose
(d) Banyan tree
Answer: (a) 25 years
(b) 3-4 months
(c) 5-7 years
(d) 200 - 300 years

Long Answer Type Questions

Question 31. Mention the number of chromosomes in following structures of maize plant.
(a) Zygote
(b) Ovule
(c) Sperm
(d) Female gamete
(e) Pollen
Answer: (a) 20
(b) 20
(c) 10
(d) 10
(e) 10

Question 32. Give one word for each of the following statements.
(a) Morphologically and genetically similar individuals.
(b) Most vital event of sexual reproduction.
(c) Morphologically distinct types of gametes.
(d) Pattern of sexual reproduction in diverse types of organisms.
(e) Motile asexual structures.
Answer: (a) Clone
(b) Fertilisation
(c) Heterogamete
(d) Similar
(e) Zoospores

Question 33. (a) Arrange the following structures in their correct sequence.
(A) (B) (C)
(b) Mention the name of structures/events A, B and C.
(c) Mention the name of plant group in which these events are shown.

Answer:

(a)

(B) (C) (A)
(b) B – gametes → C – Fusion → A – zygote
(c) Algae

Question 34. Give correct answers for the given below questions.
A B
(a) Identify the vegetative propagule.
(b) Label part A and B.
(c) This structure is involved in which type of reproduction?
(d) Do the progeny produced can be considered as clone?
(e) Mention name of two more underground vegetative propagules.

Answer:

(a) Tuber of potato

(b) A – Eyes, B – Germinating eye buds

(c) Vegetative reproduction

(d) Yes, because for the formation of new individual there is involvement of one parent.

(e) Rhizome, Bulb

Question 35. (a) Mention the terms used to denote bisexual condition and unisexual condition in lower plants.
(b) Compare Marchantia and Chara w.r.t. sexuality.
(c) Mention the factors that regulate the reproductive processes and the associated behavioural expression of organism.
(d) Explain senescent phase.

Answer:

(a) Bisexual – Monoecious, homothallic

Unisexual – Dioecious, heterothallic

(b)

(c) Both external as well as internal factors control reproductive processes. In both plants as well as animals hormones are responsible for the transition between three phases of life cycle.

(d) Senescent phase involve concomitant changes in the body like slowing of metabolism, leading to senescence or old age ultimately leading to death.

Question 36. (a) How can you justify inspite of having great variation in external, internal structure and physiology, sexual reproduction in organisms share a similar pattern?
(b) Give the name of events w.r.t. formation of following structures.
(i) Embryo
(ii) Fruit
(iii) Fusion of gamete
(iv) Gamete transfer
(v) Gamete formation

Answer:

(a) In all the organisms three distinct stages are involved during sexual reproduction in a sequential manner i.e.,

(i) Pre-fertilisation

(ii) Fertilisation

(iii) Post-fertilisation

(b) (i) Post-fertilisation

(ii) Post-fertilisation

(iii) Fertilisation

(iv) Pre-fertilisation

(v) Pre-fertilisation

Question 37. (a) Explain zygote formation.
(b) Features of zygote.
(c) Significance of zygote.

Answer:

(a) The most vital event of sexual reproduction is fusion of gametes which results in the formation of zygote. This process is called fertilisation or syngamy.

(b) (i) Universally formed in sexually reproducing organisms.

(ii) Single celled

(iii) Diploid

(iv) Thin or thick-walled

(v) Can be formed inside or outside the body of organism.

(c) It contains all the genetical information for the formation of new individual so it is a vital link that ensures continuity of species between organisms of one generation and the next.

Thick walled zygote produced in algae and fungi is resistant to desiccation and damage, so helped the organism to tolerate adverse conditions.

Question 38. Give five main distinguishing features of sexual reproduction.

Answer:

a. Involves fusion of male and female gamete.

b. Resulting in formation of zygote which develops to form individual.

c. It can be uniparental or biparental.

d. Progeny produced through sexual reproduction shows variations which gives survival advantage.

e. Involves three events i.e., pre-fertilisation, fertilisation and post-fertilisation.

Question 39. Name few methods/structure through which asexual reproduction occurs. Explain two specialized asexual structures.

Answer:

Methods/structures involved in asexual reproduction:

a. Binary fission

b. Budding

c. Zoospore

d. Conidia

e. Vegetative propagule (offset, tuber, bulbil, ginger, bulb, sucker)

Zoospore – Motile microscopic asexual structures produced in algae. Conidia – Non motile asexual structures produced in fungi.

Question 40. (a) What is life span?
(b) Correlate life span, size, complexity of organism.
(c) Can certain organisms escape harsh reality of life i.e., "Natural death"?
(d) Give life span of
(i) Banana
(ii) Banyan tree
(iii) Fruit fly
(iv) Butterfly

Answer:

(a) Life span is the time period from birth to the natural death of an organism.

(b) Life span of an organism is not necessarily related with size or complexity of organism.

(c) Unicellular organisms as they mature they divide forming two daughter cells. So process of senescence or old age is absent.

(d) (i) 25 years

(ii) 200 - 300 years

(iii) 30 days

(iv) 1 - 2 weeks

Question 41. Fill the correct options for following plants :
Monoecious/Dioecious Gamete transfer
(a) Chara
(b) Marchantia
(c) Cucurbits
(d) Papaya
(e) Date palm

Answer:

Question 42. (a) Give one example of organism which reproduces through budding.
(b) Give diagrammatic representation of this mechanism.
(c) Also differentiate it from binary fission (three points).

Answer:

(a) Yeast – Unicellular fungi

Bud

(b)

Parent cell

Question 43. Mark true or false for the given below statements. Give correct explanation of false statements.
(a) Vegetative reproduction is a type of asexual reproduction.
(b) Axillary bud arises from notches of leaves in Bryophyllum.
(c) Hormones are responsible for transition in three phases of life cycle in plants only.
(d) Gametes are universally haploid.
(e) Sweet potato produces bisexual flowers.

Answer:

(a) True

(b) False, these are adventitious buds.

(c) False, both plants and animals.

(d) True

(e) True

Question 44. (a) What kind of development takes place in the zygote in organisms with haplodiplontic and haplontic life cycle?
(b) Name the plant groups which shows this life cycle pattern.

Answer:

(a) In haplodiplontic life cycle, zygote will not undergo meiosis rather it shows mitosis forming multicellular diploid phase i.e., sporophytic one. Sporophyte forms spore mother cells which work as meiocyte forming haploid spores. In haplontic life cycle, zygote undergoes meiosis forming haploid spores.

(b) Haplodiplontic life cycle – Bryophytes, pteridophytes

Haplontic life cycle – Most of algae

Question 45. (a) Differentiate between monoecious and dioecious plant. Site three examples each.
(b) What terms are utilised for bisexual and unisexual condition in several fungi?

Answer:

(a)

(b) Bisexual – Homothallic, monoecious

Unisexual – Heterothallic, dioecious