Biology · Environmental Studies

Plant Reproduction and Germination

892 Questions

Plant reproduction and germination involve seed structure, cotyledon function, and dispersal mechanisms. These core botany concepts frequently appear in general science sections. Practice these questions to ensure better retention.

Seed germination typesSeed dispersal mechanismsCotyledons and albuminous seedsCryptogamic plantsPhanerogams reproduction

Plant Reproduction and Germination Questions

Multiple choice biology plant growth seed dormancy fruit plants: structure and function

Which of the following action makes a seed coat becomes permeable to water?

  1. Scarification

  2. Stratification

  3. Vernalization

  4. All of the above
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Scarification involves weakening, opening or altering the coat of a seed to encourage the germination. It can be done mechanically, thermally and chemically. This will make the seed coat permeable for water and air, which will help in germination of seeds.

Stratification is the process of pretreating the seed to stimulate natural condition that a seed must endure before germination. It involves soaking and chilling of seeds prior to sowing.
Vernalisation is the induction of plant's flowering process by exposure to the prolonged cold of winter. It literally has to be chilled in order to reproduce.
Somewhere, all these processes are used to break the dormancy the seeds naturally as well as artificially
So, the correct answer is 'Scarification'

Multiple choice biology plant growth seed dormancy fruit plants: structure and function

Which of the following conditions is needed by almost all seeds to break dormancy?

  1. Exposure to light

  2. lmbibition

  3. Abrasion of the seed coat

  4. Exposure to cold temperatures
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Seed dormancy allows seeds to overcome periods that are unfavourable for seedling established and is therefore important for plant ecology and agriculture. Several processes are known to be involved in the induction of dormancy and in the switch from the dormant to the terminating state. Imbibition is a special type of diffusion when water is absorbed by solids-colloids causing an enormous increase in volume. If it were not for the pressure due to imbibition, seedlings would not have been able to emerge out of the soil into the open; they probably would not have been able to establish.

So the correct option is 'Imbibition'.

Multiple choice biology plant growth seed dormancy fruit plants: structure and function

Seed dormancy is associated with

  1. Hard seed coat

  2. Immature embryo

  3. Presence of germination inhibitors

  4. All of these
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation
Seed dormancy is defined as a state in which seeds are prevented from germinating even under environmental conditions normally favourable for germination. There are a few main causes of seed dormancy, such as hard seed coat, which are impermeable to water and gases so restrict water uptake and oxygen exchange. The immature embryo that is seeded with small and undeveloped embryos do not germinate. Germination inhibitors that is Seeds contain some chemical plant growth regulators, which inhibit seed germination.
So, the correct option is, 'all of these'.
Multiple choice biology plant growth seed dormancy fruit plants: structure and function

Seed dormancy can be broken by the following combination of chemicals

  1. ${GA} _{3}$, IAA, ABA
  2. $KN{O} _{3}$, ${GA} _{3}$ and ethylene chlorohydrin

  3. NAA, 2, 4, 5-T and IAA
  4. ABA, BAP and ${GA} _{3}$
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Seed dormancy is induced in plants under unfavorable condition due to growth inhibitor hormone-like abscisic acid. Gibberellin is most commonly used to breaks the seed dormancy and induce flowering under normal condition. Apart from this, other chemicals are used to break the seed dormancy. These chemicals include potassium nitrate (KNO$ _3$), thiourea and ethylene chlorhydrin.

Thus, the correct answer is option B.

Multiple choice botany diversity in living things and their classification plant life cycle alternation of generations life span

In the first year of a biennial plant, .......... grows then it enters a period of dormancy over the cold months

  1. Leaves

  2. Stem

  3. Roots

  4. All of the above
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

In the first year of a biennial plant, the plant typically develops its vegetative structures, including leaves, stems, and roots, to store energy. These structures allow the plant to survive the winter dormancy period before flowering in the second year.

Multiple choice botany diversity in living things and their classification plant life cycle alternation of generations life span

In first year, biennial plants are only

  1. Reproductive

  2. Vegetative

  3. Both A and B

  4. None of the above
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Biennial are plants whose entire life cycle occurs within two years. In the first year, these plants are only vegetative, meaning that they don't produce reproductive structures. Rather, these plants will grow roots below ground and a small rosette of leaves near the surface

Multiple choice botany types and parts of plants plant life cycle alternation of generations life span

Plants which flower only once are

  1. Pericarpic

  2. Monocarpic

  3. Polycarpic

  4. Cleistocarpic
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Monocarpic plants flower only once in their lifetime and die immediately after the seeds are set. Also known as hapaxanth and semelparous these plants may take a long time to flower and set seeds.Example of this type of plants is Agave americana, which takes many years to flower once at times more than 50 years. 

So, the correct answer is 'Monocarpic'

Multiple choice botany types and parts of plants plant life cycle alternation of generations life span

A plant lives for less than one year is called

  1. Annual

  2. Biennial

  3. Semi-annual

  4. Perennial
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

A plant which can be grown only once in a year is an annual plant. A plant lives for less than one year is also called an annual plant because it cannot be grown again to complete two lifetimes in just one year.

So, the correct answer is "annual'.

Multiple choice botany types and parts of plants plant life cycle alternation of generations life span

Some plants flower only once in their life, generally after 50 - 100 years. They produce a large number of fruits and die

  1. Strobidanthus kunthiana

  2. Bamboo

  3. Callistemon linearis

  4. Cymbopogon reptocus
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Bamboo flower only once in their life, generally after 50 - 100 years. They produce a large number of fruits and die. They rely on seed to perpetuate themselves. 

Strobidanthus kunthiana flowers one in twelve years.
Callistemon linearis flowers normally in spring and early summer every year.
Cymbopogon reptocus is a lemon grass which rarely flowers and has no specific pattern of flowering. It is a monocot.
So, the correct answer is option B. 

Multiple choice botany types and parts of plants plant life cycle alternation of generations life span

Plants that perform their entire life from seed to flower and then to seed within a single growing season is known as

  1. Annuals

  2. Biennials

  3. Perennials

  4. None of the above
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

A- Annuals are plants that perform their entire life cycle within a single growing season. While biennials complete their life cycle in two years & Perennials live for more than two years.

Multiple choice botany types and parts of plants plant life cycle alternation of generations life span

A biennial plant is one which ___________________.

  1. Lives for two years but flowers towards the end of the second year

  2. Produces two sets of flowers in a year

  3. Grows during the second year from seeds shed turning the previous year

  4. Lives and grows from year to year
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

A biennial plant completes its life cycle in two years. It grows vegetatively in the first year and flowers, produces seeds, and dies in the second year.

Multiple choice botany types and parts of plants plant life cycle alternation of generations life span

Which kind of life-cycle pattern is exhibited by seed-bearing plants?

  1. Haplontic

  2. Diplontic

  3. Haplo-diplontic

  4. All of these
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

In a diplontic life cycle, the dominant free-living phase is the diploid (2n). The sporophyte is photosynthetic. The gametophytic phase is represented by single to few-celled haploid gametophyte. All seed-bearing plants, i.e., gymnosperms and angiosperms exhibit this type of life cycle.

So the correct option is B.

Multiple choice biology reproduction and modification in plants importance of pollination flower: parts of a flower flower and pollination

Even in absence of pollinating agents seed setting is assured in 

  1. Commelina

  2. Zostera

  3. Salvia

  4. Fig
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Even in absence of pollinating agents, seed setting is assured in Commelina, which is also called as 'Asiatic dayflower'. They lack nectar, they offer only pollen as a reward to their visitors. To attract pollinators, the plant has three types of brightly coloured floral organs: the large blue petals, fertile yellow anthers and infertile yellow antherodes that lack pollen.

Multiple choice biology the flower importance of pollination flower: parts of a flower flower and pollination

Seeds are products of sexual reproduction because they

  1. Give rise to new plants

  2. Have variability

  3. Are formed by fusion of gametes

  4. Are formed by fusion of pollen tube
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Double fertilization in angiosperms triggers the transformation of ovule into a seed. The zygote delvelops into an embryo. In double fertilization, one male gamete fuses with the egg to form the diploid zygote, the other male gamete fuses with the two polar nuclei to form the triploid primary endosperm nucleus.

So, the correct answer is 'Are formed by fusion of gametes'.