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Q1. Nuclear membrane is absent in

• Monera
• Protista
• Fungi
• Plantae

Solution

Organisms belonging to Kingdom Monera lack a nuclear membrane. Their nuclear material lies distributed in the cytoplasm.

Q2. Parthenogenesis can be observed in

• Taenia
• Earthworm
• Tapeworm
• Aphid

Solution

Parthenogenesis is a modified form of sexual reproduction in which the egg develops into a complete organism without fertilisation. It is observed in bees, rotifers, aphids and crustaceans.

Q3. Which of the following is monoecious?

• Cockroach
• Marchantia
• Date palm
• Chara

Solution

Chara is monoecious as the male and female sex organs develop on the same plant body, while the rest are dioecious.

Q4. During favourable conditions, Amoeba reproduces by

• Binary fission
• Multiple fission
• Both of these
• None of the above

Solution

Amoeba reproduces through multiple fission under unfavourable conditions.

Q5. In grafting, the portion to be grafted on the main plant is called

• Adventitious bud
• Stem
• Stock
• Scion

Solution

Adventitious buds are subnormal buds found at points along the stem. The stem is the trunk portion of the plant. The stock is the rooted supporting portion of one plant which is used for grafting.

Q6. External fertilisation occurs in the majority of

• Algae
• Fungi
• Liverworts
• Mosses

Solution

External fertilisation takes place outside the body of the organism. It is mostly observed in aquatic organisms.

Q7. Choose the correct statement from among the following:

• Dioecious (hermaphrodite) organisms are seen only in animals.
• Dioecious organisms are seen only in plants.
• Dioecious organisms are seen both in plants and animals.
• Dioecious organisms are seen only in vertebrates.

Solution

Dioecious species have distinct male and female individuals. Dioecious organisms are seen both in plants (Nepenthes) and animals (Rabbit).

Q8. Menstrual cycle is completed in

• 30 days
• 31 days
• 28 days
• 27 days

Solution

It takes 28 days for the completion of one complete menstrual cycle.

Q9. Corm is a modification of

• Root
• Leaf
• Stem
• Bud

Solution

Corms are highly condensed and specialised underground stems which bear many buds.

Q10. As compared to a normal adult male, the basal metabolic rate of a normal adult female is

• Lower
• Higher
• Same
• Almost the same

Solution

The basal metabolic rate of a normal adult male is about 1600 Kcal/day, whereas that of a normal adult female is 1520 Kcal/day.

Q11. The ‘eyes’ of the potato tubers are

• Root buds
• Flower buds
• Shoot buds
• Axillary buds

Solution

The tubers are modified underground stem branches having several buds. Each eye of the potato tuber is a bud which grows into a new potato plant.

Q12. There is no natural death in single-celled organisms like Amoeba and bacteria because

• They cannot reproduce asexually.
• They reproduce by binary fission.
• The parental body is distributed among the offspring.
• They are microscopic.

Solution

There is no natural death in single-celled organisms like Amoeba and bacteria because there is no dead body left. After binary fission, the parent continues to live as two daughter individuals.

Q13. In males, urethra carries

• Sperms only
• Urine only
• Both of these
• None of the above

Solution

In males, the urethra is the common passage for carrying sperms and urine.

Q14. Vegetative propagation in mint occurs by

• Offset
• Sucker
• Rhizome
• Runner

Solution

Vegetative propagation in mint occurs through suckers. Vegetative reproduction is a type of asexual reproduction for plants; it is a process by which new plants arise from the vegetative parts without the production of seeds or spores.  Propagation through offsets occurs in Pistia. Propagation through rhizomes occurs in Typha, Canna, ginger, turmeric and lotus. Propagation through runners occurs in Cynodon, Oxalis and Centella.

Q15. Vegetative propagation in Pistia occurs by

• Stolon
• Offset
• Runner
• Sucker

Solution

Propagation through stolons occurs in Fragaria and Vallisneria. Propagation through suckers occurs in Mint and Chrysanthemum. Propagation through runners occurs in Cynodon, Oxalis and Centella.

Q16. Vegetatively propagated plants are

• Genetically similar
• Genetically dissimilar
• Do not bear roots
• Do not form buds

Solution

Vegetatively propagated plants are genetically similar. They form true roots, buds and shoots.

Q17. Transverse binary fission occurs in

• Amoeba
• Paramoecium
• Hydra
• Euglena

Solution

  Amoeba reproduces by simple irregular binary fission. Hydra reproduces by budding. Euglena reproduces by longitudinal binary fission.

Q18. Embryo sac is found in

• Endosperm
• Ovule
• Embryo
• Seed

Solution

The embryo sac is a structure within a plant ovule which contains the egg cell. It develops from the megaspore and contains the embryo plant and endosperm after fertilisation.

Q19. Period of pregnancy is called

• Gestation period
• Incubation period
• Pre-patent period
• Blastulation

Solution

The incubation period is the time elapsed between exposure to a pathogenic organism, a chemical or radiation and when symptoms and signs are first apparent. Pre-patent period is the period between infection with a parasite and the demonstration of the parasite in the body. Blastulation is the early developmental stage of an animal consisting of single, spherical layer of cells enclosing a hollow central cavity.

Q20. Layering is of two types—air layering and mound layering. Of the two, Bougainvillea is grown by which method?

• Air layering
• Mound layering
• Both air and mound layering
• Bougainvillea cannot grow by layering

Solution

Bougainvillea is vegetatively grown by the process of air layering.

Q21. Offspring formed by sexual reproduction exhibit more variation than those formed by asexual reproduction  because

• Sexual reproduction is a lengthy process.
• Gametes of parents have qualitatively different genetic composition.
• Genetic material comes from parents of two different species.
• Greater amount of DNA is involved in sexual reproduction.

Solution

Offspring formed by sexual reproduction exhibit more variation than those formed by asexual reproduction because gametes of parents have qualitatively different genetic composition. This results in variation which is essential for generating diversity in organisms.

Q22. Strobilanthes kunthiana bears flowers every _____ years.

• 1
• 0.5
• 10
• 12

Solution

Strobilanthes kunthiana bears flowers once every 12 years between September and October.

Q23. The product of sexual reproduction generally generates

• Prolonged dormancy
• New genetic combination leading to variation
• Large biomass
• Longer viability of seeds

Solution

Sexual reproduction involves mixing of parental genetic material. This results in new genetic combination leading to variation which contributes to evolution of species.

Q24. Eichhornia is also known as

• Water hyacinth
• Banana
• Lotus
• Lily

Solution

Water hyacinth belongs to the genus Eichhornia.

Q25. Which part would be most suitable for raising virus-free plants for micropropagation?

• Bark
• Vascular tissue
• Meristem
• Node

Solution

Meristem consists of actively dividing cells. Hence, it is the most suitable part for raising virus-free plants for micropropagation.

Q26. Why asexual reproduction is sometimes disadvantageous?

• It allows animals which do not move around to produce offspring without finding mates.
• It allows an animal to produce many offspring quickly.
• It saves the time and energy of gamete production.
• It produces genetically uniform populations.

Solution

Asexual reproduction produces genetically uniform populations. It does not result in variation, which is a key for the mechanism of evolution.

Q27. Banana is vegetatively propagated by

• Tubers
• Rhizomes
• Bulbs
• Suckers

Solution

Propagation through tubers occurs in potato. Propagation through suckers occurs in mint and Chrysanthemum. Propagation through bulbs occurs in onion, lilies and garlic.

Q28. An edible part of cauliflower is

• Bract
• Bud
• Leaves
• Inflorescence

Solution

The edible part of cauliflower is the inflorescence which we use as a vegetable.

Q29. Merozoites are formed by the process of

• Sporogony
• Schizogony
• Binary fission
• Sporulation

Solution

In Plasmodium, when multiple fission takes place in the active adult form (schizont), the process is called schizogony. The daughter cells thus formed are called merozoites.

Q30. When seeds are attached to the parent plant, the type of germination is known as

• Ovipary
• Vivipary
• Epigeal
• Hypogeal

Solution

Ovipary refers to the development of a fertilised egg outside the body of the organism. Epigeal germination takes place above the ground. Hypogeal germination takes place below the ground.

Q31. In certain plants, flowering is regulated by

• Duration of day and night
• Fertilisers
• Moisture
• Age of the plant

Solution

Flowering in plants is regulated by the length of the light phase (day) and the length of the dark periods (night).

Q32. Micropropagation is a technique

• For production of true to type plants
• For production of haploid plants
• For production of somatic hybrids
• For production of somaclonal plants

Solution

Micropropagation includes propagation of plants by culturing cells, tissues and organs to produce true to type plants.

Q33. In which of the following organisms is self-fertilisation observed?

• Liver fluke
• Fish
• Earthworm
• Flatworm

Solution

Self-fertilisation requires only one organism. It occurs in liver fluke. Cross-fertilisation occurs in fish, earthworm and flatworm.

Q34. The part where the fertilisation of the ovum takes place in rabbit, humans and other placental mammals is

• Ovary
• Uterus
• Vagina
• Fallopian tube

Solution

In rabbits, humans and other placental mammals, internal fertilisation takes place inside the fallopian tube.

Q35. Which of the following is a hermaphrodite?

• Ant
• Cockroach
• Earthworm
• Aphids

Solution

Earthworm has both male and female sex organs in the same organism. It is bisexual.

Q36. Hydra reproduces asexually through

• Fragmentation
• Budding
• Binary fission
• Sporulation

Solution

Fragmentation occurs in Spirogyra. Binary fission occurs in Amoeba, Paramoecium and Euglena. Sporulation is the mode of reproduction in fungi.

Q37. Man is

• Unisexual
• Bisexual
• Hermaphrodite
• Protogynous

Solution

Unisexual organisms have separate male and female sexes.

Q38. In grafting, the point where the stock and scion are joined is sealed off with wax and clay to

• Prevent the entry of pathogens and prevent the loss of water
• Hold the two in place firmly till they are joined naturally
• Make the joint permanent
• Hasten the process of grafting

Solution

In grafting, the point where the stock and scion are joined is sealed off with wax and clay to prevent the entry of pathogens and prevent the loss of water due to evaporation. 

Q39. The process of release of the egg from the ovary is called

• Reproduction
• Ovulation
• Menstruation
• Insemination

Solution

Reproduction is the ability of the organism to produce a copy like itself. Menstruation is the periodic discharge of blood and mucosal tissue from the uterus and vagina. Insemination is the deliberate introduction of sperm into a female animal or plant for impregnating or fertilising the female for sexual reproduction.

Q40. Animals that reproduce by laying eggs are

• Oviparous
• Ovoviviparous
• Viviparous
• None of these