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 biology multicellular structure: tissue defense mechanism in plants epidermal tissue system kinds of plant tissue permanent tissues and their types

If all the lenticels of stem are blocked, the first to die will be

  1. Leaves

  2. Shoot tips

  3. Roots

  4. None of the above

Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

A lenticel is mainly the opening present on the periderm of the secondarily thickened organs and the bark of woody stems and roots of dicotyledonous flowering plants. It is a porous tissue consisting of cells with large intercellular spaces. It helps in the direct exchange of gasses between the internal tissues and atmosphere through the bark, which is otherwise impermeable to gasses. Lenticels are found in most of the woody trees but absent is  woody climbers. If lenticels are blocked then root will die first due to lack of gaseous exchange. Thus, option C is correct.

Multiple choice biology multicellular structure: tissue defense mechanism in plants epidermal tissue system kinds of plant tissue permanent tissues and their types

In the leaf, vascular bundles are found in

  1. Veins

  2. Palisade tissue

  3. Upper epidermis

  4. Lower epidermis

Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

A vascular bundle is a part of the transport system in vascular plants. The transport itself happens in vascular tissue, which exists in two forms: xylem and phloem. These are generally present in the veins of the leaf where the xylem channelizes the water and phloem conducts the prepared food from the source to the sink.

Thus, the correct answer is option A.

Multiple choice biology multicellular structure: tissue defense mechanism in plants epidermal tissue system kinds of plant tissue permanent tissues and their types

Bulliform cells that help in the folding down of lamina in drought are present in the epidermis of

  1. Monocotyledonous grass leaf

  2. Dicotyledonous leaf

  3. Both A and B

  4. None of the above

Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Bulliform cells  are so called because of its peculiar bubble shape. It mainly occurs on the upper surface of the leaves present in grasses. Water present in these cells helps to maintain its shape but loss of turgor pressure during the stress allows the leaves to roll up. During drought, the loss of moisture through vacuoles induces bulliform cells to cause the leaves of many grass species to close as the two edges of the grass blade fold up toward each other. Once adequate water is available, these cells enlarge and the leaves open again. Bulliform cells are present in only monocot leaf and absent in dicot leaf. 
Thus, the correct answer is option A.

Multiple choice biology multicellular structure: tissue defense mechanism in plants epidermal tissue system kinds of plant tissue permanent tissues and their types

In which plant part, laticiferous gland are found?

  1. Cortex

  2. Epidermis

  3. Endodermis

  4. Vascular bundle

Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Laticiferous vessels are the specialized thin walled parenchymatous cells that secrete latex and are found in the cortex. They lack pits and are composed of cellulose and hemicelluloses and serve to secrete latex. 

Epidermis is the outermost covering of the primary plant body and is mostly represented by a single layer of compactly arranged, barrel-shaped parenchyma cells. 
The innermost layer of cortex forms endodermis, which has compactly arranged barrel shaped cells. The primary thin walled endodermis shows suberin deposition in form of bands or strips that run around the radial and end walls of the cells and forms Casparian strips. 
Vascular bundle consists of xylem, phloem, and cambium (in dicot only), which are derived from procambium and serve in translocation of food and sap.
So, the correct answer is option A.

Multiple choice biology multicellular structure: tissue defense mechanism in plants epidermal tissue system kinds of plant tissue permanent tissues and their types

Vascular layers of plant body shows

  1. Protective tissue

  2. Epithelial tissue

  3. Meristematic tissue

  4. None of the above

Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Vascular bundles of the plant show vascular cambium or cork cambium. Cork cambium is involved in making cork. Cork is a nonliving, water resistant tissue formed in many plants to prevent water loss. Cork cells are dead and have cell walls composed of a waxy substance "suberin" which is highly impermeable to gasses and water. This substance prevents the water loss from the stem. Cork also protects the plant from wear and tear. Hence, it is a protective type of tissue. Therefore, option A is correct.  

Multiple choice botany asexual and sexual reproduction in plants structure of male and female reproductive structures structure of ovule gynoecium

The nucellus of the ovule is:

  1. haploid

  2. diploid

  3. triploid

  4. polyploidy

Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

In seed plants, Ovule is the part of the female reproductive organ. It consists of three parts; Integument ( forming its outer layer) Embryo sac ( female gametophyte) and a Nucellus that is the central and largest part of the ovule as a source of nutrients for the embryo and its ploidy is diploid i.e 2n
Nucellus is derived from the apical portion of the ovule primordium of the ovule primordium and function as a megasporangium i.e, the nucellus produces the megasporocyte, which will undergo meiosis to form megaspores that is the reason that nucellus of the ovule is diploid in nature.
So, the nucellus of ovule is diploid.

So, the correct answer is 'diploid'.

Multiple choice botany asexual and sexual reproduction in plants structure of male and female reproductive structures structure of ovule gynoecium

Ovule represents

  1. Microsporangium

  2. Megasporangium

  3. Gametophyte

  4. Embryo.

Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation
 Microsporangium  Pollen grains or male gamete
 Megasporangium  Ovules or female gamete
 Gametophyte  Sexual phase in the life cycle of the plant
 Embryo  Part of a seed, which is formed after fertilization

So, the correct answer is 'Megasporangium'

Multiple choice botany asexual and sexual reproduction in plants structure of male and female reproductive structures structure of ovule gynoecium

An angiospermic plant has to produce $88$ viable embryo sacs. How many meiotic divisions will be needed to produce equal number of female gametophytes by this plant?

  1. $88$
  2. $22$
  3. $44$
  4. $132$
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation
Ovule contains the female gametophyte or the embryo sac. Each ovule usually contains only one embryo sac
Each embryo sac is formed by meiotic division of the diploid mother cell
The end result of a meiotic division is 4 haploid cells, in most cases, of the 4 haploid cells formed, three degenerate and  one develops into the embryo sac 
Therefore, to produce 88 viable embryo sacs 88 meiotic divisions are required
So, the correct answer is '88'
Multiple choice botany asexual and sexual reproduction in plants structure of male and female reproductive structures structure of ovule gynoecium

The female reproductive system produces haploid (n) gametes called ............. or egg cell.

  1. Ovum

  2. Endosperm

  3. Pollen grains

  4. Synergids

Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

A. Female gametes are also called eggs or ovum. They are created during the cellular reproduction process known as meiosis. The resulting gamete cell is a haploid cell.

B. The endosperm is a tissue produced inside the seeds of most of the flowering plants following fertilization, It surrounds the embryo and provides nutrition.
C. pollen grains are the granular microspores that occur in pollen and give rise to male gametophyte of a seed plant and they are haploid.
D. The synergids are part of the egg apparatus and are thought to help the pollen nucleus reach the egg cell for fertilization.
So, the correct answer is "ovum".

Multiple choice botany asexual and sexual reproduction in plants structure of male and female reproductive structures structure of ovule gynoecium

Androphore is lightly differentiated in the flower of .................

  1. $Rafflesia$
  2. $Calycanthus$
  3. $Salvia$
  4. $Passiflora$
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

When in a flower, the internode between the corolla and the androecium is lengthened so as to raise the androecium high up in the air then that internode is called Androphore. It is an extension of the receptacle carrying the androecium and the gynoecium, typical of the caper family. In Passiflora, androphore is lightly differentiated.

Multiple choice botany asexual and sexual reproduction in plants structure of male and female reproductive structures structure of ovule gynoecium

When pollen tube enters through the base of a funiculus or the integument the phenomenon is known as

  1. Porogamy

  2. Chalazogamy

  3. Mesogamy

  4. Isogamy

Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

When pollen tube enters through the micropyle, the phenomenon is known as porogamy. When pollen tube enters to the embryo sac through the tissue of the chalaza, the phenomenon is known as chalazogamy. When pollen tube enters through the base of a funiculus or the integument, the phenomenon is known as mesogamy. Isogamy is a form of sexual reproduction that involves fusion of gametes of similar size and structure. 

Thus, the correct answer is option C.

Multiple choice botany asexual and sexual reproduction in plants structure of male and female reproductive structures structure of ovule gynoecium

Ovule is comparable to ............

  1. Megasporangium

  2. Microsporangium

  3. Microsporophyll

  4. Megasporophyll

Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Ovule means 'small egg'. In seed plants, the ovule is the surface that gives rise to and contains the female reproductive cells. It consists of three parts: the integuments form its outer layers, the nucellus and female gametophyte in its center. The female gametophyte specifically termed as megagametophyte is also called the embryo sac in angiosperms.

Multiple choice botany asexual and sexual reproduction in plants structure of male and female reproductive structures structure of ovule gynoecium

Nurse tissue of ovule is .............

  1. Nucellus

  2. Chalaza

  3. Hilum

  4. Micropyle

Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The mature ovule contains in its central part a region called the nucellus that in turn contains an embryo sac with eight nuclei, each with one set of chromosomes. The two nuclei near the centre are referred to as polar nuclei. In the pines, the female gametophyte develops within the tissues of the nucellus and acquires abundant food reserves. The proembryo forms after a period of free-nuclear division in the zygote, and the tier of cells above the basal four then elongates to form a suspensor which pushes the embryonic group deep into the gametophyte.