Biology · Science General

Botany and Plant Science

4,989 Questions

Botany and plant science delve into the biological study of plant life, covering structural anatomy, physiological processes, and reproductive mechanisms. Key topics include inflorescence patterns, root modifications, and seed development, which are vital for biology sections in medical entrance exams. This collection of practice questions helps solidify understanding of complex plant functions.

Plant ReproductionPlant AnatomyRoot ModificationsInflorescence PatternsPlant Morphology

Botany and Plant Science Questions

Multiple choice botany modes of reproduction introduction to flower pre fertilization - plants sexual reproduction in flowering plants the origin of cells and cell division

Mesogamy is

  1. Fusion of similar male and female gametes

  2. Fusion of morphologically different but physiologically similar gametes

  3. Entry of pollen tube through the integument

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

There are various ways by which the pollen tube can reach embryo sac for pollination.

Porogamy is the condition when the pollen tube enters the ovule from the micropylar end. Chalazogamy is the condition of entering of pollen tube from chalaza. Mesogamy is when pollen tube enters via the integuments.
Fusion of male and female gametes refers to as fertilization or fusion of gametes.
So, the correct option is 'entry of the pollen tube through the integument'. 

Multiple choice botany modes of reproduction introduction to flower pre fertilization - plants sexual reproduction in flowering plants the origin of cells and cell division

What is the function of the filiform apparatus at the entrance into ovule?

  1. Guides pollen tube from synergid to egg

  2. Helps in the entry of pollen tube into a synergid

  3. Prevents entry of more than one pollen tube into a synergid

  4. Brings about opening of the pollen tube
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation
A fully developed typical or polygonum type of embryo sac is a large and oval structure consisting of 7 cells and 8 nuclei.
Egg apparatus- this is a group of 3 cells situated at the micropylar end. The centrally located cell is known as the egg cell. On its sides are present two synergids. An egg cell has a large vacuole at its upper end and a prominent nucleus near its lower end. Synergids show of filiform apparatus attached to the upper wall. It is known to attract and guide the pollen tube. Each of the synergies has a vacuole at its lower end and the nucleus at its upper end.

So, the correct option is 'Helps in the entry of the pollen tube into a synergid'.
Multiple choice botany modes of reproduction introduction to flower pre fertilization - plants sexual reproduction in flowering plants the origin of cells and cell division

What is the function of filiform apparatus in an angiospermic embryo sac?

  1. Guides pollen tube from synergid to egg

  2. Helps in the entry of more than one pollen tube into a synergid

  3. Prevents entry of more than one pollen tube into a synergid

  4. Brings about opening of the pollen tube.
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The function of filiform apparatus in an angiospermic embryo sac is to guide the entry of pollen tube from synergid to egg. The synergid cells present within the female gametophyte play a vital role in the reproduction process in angiosperm. The cell wall of synergid develops an extremely thick structure called the filiform apparatus at the micropylar end of the ovule.

So, the correct answer is 'Guides pollen tube from synergid to egg'.

Multiple choice botany modes of reproduction introduction to flower pre fertilization - plants sexual reproduction in flowering plants the origin of cells and cell division

The most common type of entry of pollentube into the ovule is

  1. Mesogamy

  2. Chalazogamyy

  3. Basigamy

  4. Porogamy
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Porogamy is the most common type in which the pollen tube enters the ovule through the micropyle. An example includes lily, etc. 

So the correct option is D.


Multiple choice botany modes of reproduction introduction to flower pre fertilization - plants sexual reproduction in flowering plants the origin of cells and cell division

Growth of the pollen tube is

  1. Apical

  2. Intercalary

  3. Basal

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

In sexual reproduction of plants, the sperm is transferred to the egg through a long, polarized tube of a pollen cell called as the pollen tube. The growth of the pollen tube is apical. It grows at its tip at very rapid rate. The rapid growth is due to a highly polarized fusion of apical vesicles. These transport cell wall components to the growing tip via cytoplasmic streaming and are incorporated into a zone of elongation in the apical region of the pollen tube. Hence, the pollen tube extends its length by apical growth in a relatively small region.

Thus, the correct answer is option A.

Multiple choice botany modes of reproduction introduction to flower pre fertilization - plants sexual reproduction in flowering plants the origin of cells and cell division

Choose the correct answers from the alternatives given.
Entrance of a pollen tube into an ovule through the micropyle is called

  1. porogamy

  2. mesogamy

  3. chalazogamy

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

After reaching ovary, the pollen tube enters the ovule. When the pollen tube enters the ovule through micropyle, it is called porogamy. It is the most common type. e.g., Lily. 

So, the correct option is, 'porogamy'.

Multiple choice botany modes of reproduction introduction to flower pre fertilization - plants sexual reproduction in flowering plants the origin of cells and cell division

Entry of pollen tube in the ovule through integument is called

  1. Chalazogamy

  2. Basigamy

  3. Mesogamy

  4. Porogamy
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation
The entry of pollen tube in the ovule through integument is commonly known as mesogamy. It is commonly seen in plants like Cucurbita, Populus, etc.
So, the correct answer is 'Mesogamy'.
Multiple choice botany modes of reproduction introduction to flower pre fertilization - plants sexual reproduction in flowering plants the origin of cells and cell division

The apical growing region of pollen tube called

  1. Growing zone

  2. Cap block

  3. Non-vacuolate region

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

Apical zone of pollen tube contains abundant vesicles but lacks cell organelles. It is hemisphere in shape and transparent in nature. This transparent apical growing region of pollen tube is called as cap block. It exists only until the tube is growing. It disappears as soon as the growth ceases. 

Thus, the correct answer is option B. 

Multiple choice botany modes of reproduction introduction to flower pre fertilization - plants sexual reproduction in flowering plants the origin of cells and cell division

The functional part of the pollen tube is separate from the rest by

  1. Vacuoles

  2. Callose plugs

  3. Septa

  4. Both B and C
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Callose is a beta-1,3-glucan. It is the major component of the pollen tube cell wall. It is also deposited within the cytoplasm as distinct callose grains. This leads to the formation of callose plugs. Callose plugs separate the living, growing and functional part of the pollen tube in the tip from the remaining degenerating part.

Thus, the correct answer is option B.

Multiple choice evs life in water aquatic plant adaptations pollination through water aquatic adaptation extreme adaptations

Root system in hydrophytes is 

  1. Fully Developed

  2. Partially Developed

  3. Absent

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

Because hydrophtes are supported by water rather than by roots and stem structures, most hydrophtes as a result have roots that are small and feathery. These are designed to take in oxygen from the water, and since the plant is fully submersed in water at all times, there is less need for a long and thick root structure. One plant that has a feathery root is the Salvinia Molesta, which is a free-floating aquatic fern.


So, the correct option is 'Partially developed'.

Multiple choice evs life in water aquatic plant adaptations pollination through water aquatic adaptation extreme adaptations

In submerged hydrophytes, the stems are extremely weak due to

  1. Absence of phloem

  2. Absence of xylem

  3. Presence of aerenchyma

  4. Poor development of xylem and mechanical tissue
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

In submerged hydrophytes, the entire plant body is involved in the absorption of water and these plants not experiences much stress or pressure internally. So in these plants, xylem and mechanical tissues are poorly developed.

So, the correct option is ‘Poor development of xylem and mechanical tissues’.

Multiple choice evs life in water aquatic plant adaptations pollination through water aquatic adaptation extreme adaptations

Finely dissected leaves occur in

  1. Free floating plants

  2. Rooted floating leaved plants

  3. Submerged plants

  4. Emerged plants
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation
Finely dissected leaves occur in submerged plants. In submerged plants, the leaves are finely dissected till the midrib. This dissection gives a feather-like appearance. In this, only the stalk of flower remains above the water and rest of the plant is submerged.
Thus, the correct answer is 'Submerged plants.'
Multiple choice evs life in water aquatic plant adaptations pollination through water aquatic adaptation extreme adaptations

Stem of submerged hydrophytes is soft and weak, because of

  1. Absence of phloem

  2. Absence of stomata

  3. Absence of xylem

  4. Feebly developed supporting tissue and xylem
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Submerged hydrophytes live entirely underwater, so they do not need rigid mechanical tissues for support because the surrounding water provides buoyancy. Consequently, their xylem and supporting tissues are poorly developed.