75 free MCQs on Reproduction in Organisms with worked answers and explanations. Asexual and sexual reproduction, flower anatomy, pollination, fertilization, and seed development.
Take the timed Reproduction in Organisms chapterwise test →Below are 75 practice questions on Reproduction in Organisms, sorted Easy → Hard. Tap “Show answer & explanation” under any question to check yourself. Want the full theory first? Read the Reproduction in Organisms notes.
Structure of a mature flower. Image: LadyofHats (Mariana Ruiz), Public Domain, via Wikimedia Commons.
Q1.
The special mass of cells that helps sponges reproduce asexually is called the:
Answer: A. Gemmule
Why: Sponges reproduce asexually by producing internal buds called gemmules, which are resistant masses of cells.
Q2.
In filamentous algae and some fungi, the motile asexual spores produced are called:
Answer: B. Zoospores
Why: Many algae and aquatic fungi reproduce asexually through motile, flagellated spores called zoospores.
Q3.
Reproduction in which offspring are formed from a single parent without gamete fusion is:
Answer: C. Asexual reproduction
Why: Asexual reproduction involves a single parent and does not involve the fusion of gametes, producing genetically identical offspring.
Q4.
The fusion of the haploid male and female gametes to form a diploid zygote is called:
Answer: D. Syngamy
Why: Syngamy (fertilisation) is the fusion of two haploid gametes to form the diploid zygote.
Q5.
In organisms like Hydra and yeast, a new individual develops as an outgrowth from the parent body. This is:
Answer: A. Budding
Why: In budding, a bud arises as an outgrowth on the parent body and detaches to become a new individual, as in Hydra and yeast.
Q6.
Grafting in plants is done to:
Answer: B. Combine desirable traits of two varieties onto one plant
Why: Grafting: shoot (scion) of one plant joined to root (rootstock) of another. Combines disease-resistant roots with high-quality fruit varieties.
Q7.
Spores in ferns are produced by:
Answer: C. Meiosis in sporangia (on undersides of fronds)
Why: Fern spores are produced by meiosis in sporangia (groups called sori) on the underside of fronds. Spores germinate into small gametophyte plants.
Q8.
In bryophytes (mosses), the dominant generation is the:
Answer: B. Gametophyte (the green plant you see)
Why: In mosses (bryophytes), the gametophyte is the dominant, independent generation. The sporophyte (spore-producing) grows on and depends on the gametophyte.
Q9.
Reproduction that involves a single parent and produces genetically identical offspring is:
Answer: C. asexual reproduction
Why: Asexual reproduction needs only one parent and yields offspring genetically identical to it (clones).
Q10.
The fusion of a male and a female gamete is called:
Answer: D. fertilisation
Why: Fertilisation (syngamy) is the fusion of two gametes to form a diploid zygote.
Q11.
Genetically identical offspring produced from a single parent are known as:
Answer: C. clones
Why: Because asexual reproduction involves no gamete fusion, the offspring are exact copies called clones.
Q12.
Binary fission is a common mode of asexual reproduction in:
Answer: A. Amoeba
Why: Amoeba divides into two daughter cells by binary fission, an asexual process.
Q13.
Reproduction involving a single parent is called what?
Answer: A. Asexual
Why: Asexual reproduction needs only one parent and no gamete fusion.
Q14.
Offspring produced by asexual reproduction are called what?
Answer: A. Clones
Why: Asexual offspring are genetically identical copies called clones.
Q15.
Amoeba reproduces asexually by which process?
Answer: A. Binary fission
Why: Amoeba divides into two by binary fission.
Q16.
Yeast commonly reproduces asexually by which method?
Answer: A. Budding
Why: Yeast reproduces asexually by forming buds.
Q17.
The fusion of two gametes forms which structure?
Answer: A. Zygote
Why: Fusion of male and female gametes produces the zygote.
Q18.
The eye of a potato tuber is used for which purpose?
Answer: A. Vegetative growth
Why: The potato eye is a bud that gives rise to a new plant vegetatively.
Q19.
Bryophyllum produces buds on which part?
Answer: A. Leaf margins
Why: Bryophyllum bears adventitious buds along its leaf margins.
Q20.
The period from birth to natural death is called the?
Answer: A. Life span
Why: Life span is the period of existence from birth to natural death.
Q21.
In which phase does an organism reproduce?
Answer: A. Reproductive
Why: Reproduction occurs during the reproductive (mature) phase of life.
Q22.
Animals that lay eggs are described as what?
Answer: A. Oviparous
Why: Egg-laying animals such as birds are oviparous.
Q23.
Animals that give birth to young ones are called what?
Answer: A. Viviparous
Why: Viviparous animals give birth to live young, e.g. most mammals.
Q24.
Male and female gametes are collectively known as what?
Answer: A. Gametes
Why: The haploid reproductive cells that fuse are called gametes.
Q25.
In flowering plants, which structure develops into a seed?
Answer: A. Ovule
Why: After fertilisation the ovule develops into the seed.
Q26.
The stage between the formation of the zygote and reproductive maturity during which the organism grows is the:
Answer: B. Juvenile phase
Why: The juvenile (vegetative in plants) phase is the period of growth before an organism becomes reproductively mature.
Q27.
In flowering plants, fertilisation is generally not immediate after pollination because:
Answer: C. The pollen tube must grow down the style to the ovule
Why: After pollination the pollen grain germinates and the pollen tube must grow down the style to reach the ovule before syngamy can occur.
Q28.
The pre-fertilisation event in which a diploid cell undergoes meiosis to form haploid gametes is:
Answer: D. Gametogenesis
Why: Gametogenesis is the process of gamete formation; in diploid organisms gametes are produced by meiosis to keep chromosome number constant across generations.
Q29.
In honeybees, drones are haploid because they develop from unfertilised eggs by:
Answer: A. Parthenogenesis
Why: Male honeybees (drones) develop from unfertilised eggs through parthenogenesis and are therefore haploid.
Q30.
An organism described as hermaphrodite, such as the earthworm, is one that:
Answer: B. Possesses both male and female reproductive organs
Why: A hermaphrodite bears both male and female sex organs in the same individual, as seen in earthworms and Taenia.
Q31.
Seed dormancy mechanisms include:
Answer: B. Hard seed coat (physical), presence of germination inhibitors (chemical), requirement for cold stratification, or light requirement
Why: Seed dormancy: prevents germination in unfavorable conditions. Mechanisms: impermeable seed coat (hard/physical); chemical inhibitors (ABA); cold requirement (vernalization); light requirement; embryo immaturity.
Q32.
The phenomenon of vivipary in plants refers to:
Answer: B. Seed or embryo germinating while still attached to the parent plant
Why: Vivipary: germination of the seed while still on the parent plant. Common in mangroves (propagules ready to root when they drop). Also occurs in some grasses in humid conditions (precocious germination).
Q33.
A monoecious plant is one that:
Answer: C. Has both male and female flowers on the same individual plant (e.g., maize, cucumber)
Why: Monoecious: separate male and female flowers on the same plant (e.g., maize: male = tassel, female = ear; cucumber, corn). Promotes cross-pollination while on same plant.
Q34.
Gymnosperm seed development differs from angiosperm in lacking:
Answer: B. A fruit (seeds are naked, not enclosed in a fruit)
Why: Gymnosperms (conifers, cycads): seeds not enclosed in a fruit (naked seeds). No ovary wall to develop into fruit. Angiosperms have seeds enclosed within fruit (evolved from ovary wall).
Q35.
The "eyes" of a potato tuber that develop into new plants are actually:
Answer: B. axillary buds
Why: Each eye is a node bearing an axillary bud; this is a form of natural vegetative propagation.
Q36.
Non-primate mammals such as cows and dogs show a reproductive cycle called the:
Answer: C. oestrus cycle
Why: Non-primate mammals show oestrus cycles; only primates (including humans) show menstrual cycles.
Q37.
An organism that bears only one kind of reproductive organ, being either male or female, is described as:
Answer: D. unisexual
Why: Unisexual (dioecious in plants) organisms carry a single sex; hermaphrodites carry both.
Q38.
In Bryophyllum, new plantlets arise from the margins of the:
Answer: C. leaf
Why: Bryophyllum leaf margins bear adventitious buds that grow into new plants - vegetative propagation.
Q39.
Which structure is the asexual reproductive unit in Chlamydomonas?
Answer: A. Zoospore
Why: Chlamydomonas reproduces asexually by flagellated zoospores.
Q40.
Penicillium reproduces asexually by which spores?
Answer: A. Conidia
Why: Penicillium forms non-motile spores called conidia.
Q41.
Which organisms reproduce asexually using gemmules?
Answer: A. Sponges
Why: Sponges produce internal buds called gemmules for asexual reproduction.
Q42.
Hydra reproduces asexually by which method?
Answer: A. Budding
Why: Hydra produces new individuals by budding.
Q43.
The cyclical secretion of sex hormones in non-primates gives which cycle?
Answer: A. Oestrus cycle
Why: Non-primate mammals show the oestrus cycle of reproductive activity.
Q44.
The menstrual cycle is characteristic of which group?
Answer: A. Primates
Why: Primates such as monkeys, apes and humans show the menstrual cycle.
Q45.
Organisms breeding only once in a lifetime are called what?
Answer: A. Semelparous
Why: Semelparous organisms reproduce a single time then die.
Q46.
Fertilisation occurring outside the female body is termed what?
Answer: A. External
Why: When gametes fuse outside the body it is external fertilisation.
Q47.
Which arrangement shows external fertilisation?
Answer: A. Frogs in water
Why: Frogs release gametes into water where external fertilisation occurs.
Q48.
The formation of gametes is broadly called what?
Answer: A. Gametogenesis
Why: The process of forming gametes is gametogenesis.
Q49.
Development of an embryo from the zygote is called what?
Answer: A. Embryogenesis
Why: Embryogenesis is the development of an embryo from the zygote.
Q50.
In which plants do bulbils serve as vegetative propagules?
Answer: A. Agave
Why: Agave produces bulbils that grow into new plants vegetatively.
Q51.
Vegetatively propagated plants such as banana and sugarcane are genetically identical to the parent and together form a:
Answer: A. Clone
Why: Vegetative propagation gives offspring genetically identical to the parent; such a group of identical individuals is called a clone.
Q52.
In diploid organisms, meiosis during gamete formation is essential because it:
Answer: C. Halves the chromosome number so syngamy restores diploidy
Why: Meiosis reduces the chromosome number to half in gametes, so that fusion of two gametes at syngamy restores and maintains the species-specific diploid number.
Q53.
In haploid-dominant organisms such as many algae and fungi, meiosis occurs:
Answer: D. In the zygote, just after its formation
Why: In organisms with a haploid parental body, the diploid zygote is the only diploid stage and undergoes zygotic meiosis to restore the haploid condition.
Q54.
A bamboo species that flowers once after many years, produces seeds and then dies, illustrates:
Answer: B. Monocarpic reproduction
Why: Monocarpic plants such as certain bamboos flower only once in their lifetime, set a large quantity of seed, and then die.
Q55.
External fertilisation, as seen in bony fishes and frogs, is characteristically accompanied by:
Answer: C. Production of a very large number of gametes
Why: Organisms with external fertilisation release huge numbers of gametes into water to offset the heavy losses and the vulnerability of offspring to predators.
Q56.
The sporophyte generation is dominant in:
Answer: C. Ferns, seed plants, and gymnosperms (not mosses/liverworts where gametophyte dominates)
Why: Sporophyte dominance: in vascular plants (ferns, gymnosperms, angiosperms), the diploid sporophyte is the main plant. In non-vascular plants (mosses), the haploid gametophyte dominates. Trend in land plant evolution.
Q57.
Chemical ecology of seed dispersal involves:
Answer: B. Seeds producing elaioisomes, fleshy fruits with colors targeting specific frugivores, or chemical repellents to keep non-dispersers away while attracting proper seed dispersers
Why: Seeds coevolve with dispersers: fruit colors match disperser color vision (red for birds, yellow/green for bats); scents attract specific animals; elaiosomes attract ants; capsaicin in chili repels mammals but not birds (birds disperse seeds long-distance).
Q58.
In a diploid organism, haploid gametes are produced by:
Answer: B. meiosis
Why: Meiosis halves the chromosome number, producing haploid gametes so that fertilisation restores the diploid state.
Q59.
A plant such as bamboo that flowers only once in its life cycle and then dies is termed:
Answer: A. monocarpic
Why: Monocarpic plants flower and fruit once, then die; bamboo may do so only after several decades.
Q60.
In sexually reproducing organisms, the diploid chromosome number of the species is restored by:
Answer: B. fertilisation
Why: Gametes are haploid; their fusion at fertilisation brings back the full diploid chromosome number.
Q61.
Water hyacinth spreads rapidly mainly through which means?
Answer: A. Vegetative growth
Why: Water hyacinth (terror of Bengal) spreads fast by vegetative propagation.
Q62.
In haploid organisms, meiosis occurs at which stage?
Answer: A. Zygote stage
Why: In haplontic organisms the zygote undergoes meiosis (zygotic meiosis).
Q63.
In diploid organisms, gametes are formed by meiosis in which cells?
Answer: A. Meiocytes
Why: Specialised diploid meiocytes undergo meiosis to form gametes.
Q64.
Which plant part in ginger acts as a vegetative propagule?
Answer: A. Rhizome
Why: Ginger propagates vegetatively through its underground rhizome.
Q65.
The offset is a vegetative propagule seen in which plant?
Answer: A. Water lettuce
Why: Aquatic plants like Pistia (water lettuce) reproduce by offsets.
Q66.
Which event marks the end of the juvenile phase in animals?
Answer: A. Sexual maturity
Why: The juvenile phase ends when the organism attains sexual maturity.
Q67.
Post-fertilisation events lead to formation of which structure?
Answer: A. Embryo
Why: After fertilisation the zygote develops into an embryo (post-fertilisation event).
Q68.
In honeybees, males develop from unfertilised eggs by which process?
Answer: A. Parthenogenesis
Why: Male honeybees (drones) arise from unfertilised eggs via parthenogenesis.
Q69.
The transfer of pollen grains before fertilisation is which type of event?
Answer: A. Pre-fertilisation
Why: Pollination is a pre-fertilisation event that precedes gamete fusion.
Q70.
Which of these is a true bisexual (monoecious) example?
Answer: A. Earthworm
Why: Earthworms are hermaphrodite, bearing both male and female organs.
Q71.
A flower with both stamens and carpels is described as what?
Answer: A. Bisexual
Why: A flower bearing both stamens and carpels is bisexual (perfect).
Q72.
In Planaria, the ability to regenerate a whole body is called what?
Answer: A. Regeneration
Why: Planaria can regrow the whole body from fragments by regeneration.
Q73.
Bamboo species typically flower after roughly how many years?
Answer: A. 50 to 100 years
Why: Many bamboo species flower once after 50 to 100 years and then die.
Q74.
Strobilanthes kunthiana (Neelakuranji) flowers at what interval?
Answer: A. Once in 12 years
Why: Neelakuranji flowers gregariously once every twelve years.
Q75.
Which phase follows the reproductive phase and precedes death?
Answer: A. Senescent phase
Why: After reproduction organisms enter the senescent (ageing) phase before death.