Biology · Science General

Botany and Plant Science

5,038 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 asexual and sexual reproduction in plants structure of male and female reproductive structures structure of ovule gynoecium

The most common type of ovule is

  1. Orthotropous

  2. Hemitropous

  3. Anatropous

  4. Campylotropous
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation
•Orthotropous ovule is the simplest and primitive type of ovule. In this type of ovule, micropyle, chalaza and funiculus lie in one vertical plane.
•Hemianatropous ovule- The body of ovule is turned through 90° and micropyle and chalaza lie in a straight line but funiculus is at right angle or 90° with both these two.
•Anatropous ovule is the most common type of ovules, which occurs in more than 80% of angiospermic families. The body of ovule is rotated by 180° and micropyle comes near to the funiculus. Chalaza and micropyle lie in the straight line but hilum is at 90° to micropyle.
•Campylotropous ovule- In this type of ovule, the length of funiculus becomes increased and it covers the whole ovule.
So, the correct answer is C.
Multiple choice botany asexual and sexual reproduction in plants structure of male and female reproductive structures structure of ovule gynoecium

Name the type of ovule in which hilum, chalazal and micropyle come to lie nearby.

  1. Campylotropous

  2. Amphitropous

  3. Both A and B

  4. Hemitropous
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

• Campylotropous ovule- This type of ovule is similar to Anatropous ovule but the curvature is less than that of an anatropous ovule. Micropyle is near to the funiculus. Chalaza and micropyle lie in the straight line but hilum is at 90° to the micropyle.

• Amphitropous ovule- The body of ovule gets curved along with the embryo sac in such a way that it becomes horseshoe-shaped.
• Hemianatropous ovule- The body of ovule is turned through 90° and micropyle and chalaza lie in a straight line but funiculus is at a right angle or 90° with both these two.
Hence, it is in Campylotropous and Amphitropous ovule in which Hilum, chalaza, and micropyle come to lie nearby. 
So, the correct answer is C.

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

Archesporium of ovule is

  1. Single celled derived from nucellar epidermis

  2. Single celled derived from nucellar hypodermis

  3. Multicellular derived from nucellar epidermis

  4. Multicellular derived from nucellar hypodermis
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

In the ovule or megasporangium, during the process of megasporogenesis, a hypodermal cell functions as a archesporium cell and becomes more prominent because of large size, denser cytoplasm and large nucleus. In tenuinucellate ovules, archesporial cell directly functions as megaspore mother cell while in crassinucellate ovules, archesporial cell divides periclinally to form an outer parietal cell and inner primary sporogenous cell that functions as megaspore mother cell.

Hence, a single hypodermal cell in the Nucellus functions as the archesporium.
So, the correct answer is B.

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

Ovule is inverted with body fused to funicle, micropyle lying close to hilum and facing the placenta. It is?

  1. Hemitropous

  2. Orthotropous

  3. Anatropous

  4. Campylotropous
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

•Hemianatropous ovule- The body of ovule is turned through 90° and micropyle and chalaza lie in a straight line but funiculus is at right angle or 90° with both these two.

•Orthotropous ovule is the simplest and primitive type of ovule. In this type of ovule, micropyle, chalaza and funiculus lie in one vertical plane.
•Anatropous ovule is the most common type of ovules, which occurs in more than 80% of angiospermic families. The body of ovule is rotated by 180° and micropylar comes near to the funiculus. Chalaza and micropyle lie in the straight line but hilum is at 90° to micropyle. The body of ovule is fused to funiculus on one side, thus forming a ridge called Raphe.
•Campylotropous ovule- This type of ovule is very similar to the Anatropous ovule but the curvature is less than the Anatropous ovule.
Hence, the properties given in the question match those of Anatropous ovule.
So, the correct answer is C.

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

The body of ovule lies straight in continuation of funicle, with funicle chalazal and micropyle in straight line. The type of ovule is?

  1. Anatropous

  2. Orthotropus

  3. Hemitropous

  4. Amphitropous
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation
•Anatropous ovule is the most common type of ovules, which occurs in more than 80% of angiospermic families. The body of ovule is rotated by 180° and micropyle comes near to the funiculus. Chalaza and micropyle lie in the straight line but hilum is at 90° to the micropyle.
•Orthotropous ovule is the simplest and primitive type of ovule. In this type of ovule, micropyle, chalaza and funiculus lie in one vertical plane i.e. in a straight line.
•Hemianatropous ovule- The body of ovule is turned through 90° and micropyle and chalaza lie in a straight line but funiculus is at a right angle or 90° with both these two.
•Amphitropous ovule- Here, the body of ovule gets curved along with the embryo sac and it becomes horseshoe-shaped.
So, the correct answer is B.

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

Circinotropous ovule occurs in

  1. Opuntia

  2. Ranunculus

  3. Polygonum

  4. Cicer
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation
In Circinotropous ovule, the length of the funiculus becomes increased and so it covers the whole ovule. Circinotropous ovule is found in the family Cactaceae. Example, Opuntia.
Ranunculus has Hemianatropous ovule in which body of ovule is turned through 90° and micropyle and chalaza lie in straight line but funiculus is at 90° to both of these.
Polygonum has Orthotropous ovule in which micropyle, chalaza and funiculus lie in a straight line.
Cicer has Anatropous ovule in which body of ovule is rotated by 180° and micropyle comes near to funiculus. Chalaza and Micropyle are in straight line but hilum is at 90° to the micropyle.
So, the correct answer is A.
Multiple choice botany asexual and sexual reproduction in plants structure of male and female reproductive structures structure of ovule gynoecium

Body of the ovule is straight but at right angles to the funicle. It is

  1. Orthotropous

  2. Campylotropous

  3. Hemitropous

  4. Amphitropous
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

•Orthotropous ovule is the simplest and primitive type of ovule. In this type of ovule, micropyle, chalaza and funiculus lie in one vertical plane.

•Campylotropous ovule- In this type of ovule, the length of funiculus becomes increased and it covers the whole ovule.
•Hemianatropous ovule- The body of ovule is turned through 90° and micropyle and chalaza lie in a straight line but funiculus is at right angle or 90° with both these two.
•Amphitropous ovule- The body of ovule gets curved along with the embryo sac in such a way that it becomes horseshoe-shaped.
Thus, in Hemianatropous ovule, the body of ovule is straight as it doesn't get curved and is turned to 90° such that it is at right angle to the funiculus.
So, the correct answer is C

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

Which is diploid structure?

  1. Pollen grains

  2. Egg

  3. Megaspore

  4. MMC
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation
•Pollen grains develop from microspores. Microspores are formed from the microspore mother cell. Microspore mother cell is diploid and undergoes meiosis to produce four haploid microspores which develop to form pollen grains. Hence, pollen grains are haploid.
•Egg is the female gamete present in the embryo sac. Egg cell is haploid and on fusion with male gamete produces a diploid zygote. Hence, egg is haploid.
•Megaspore is formed from the megaspore mother cell. Megaspore mother cell is diploid and undergoes meiosis to produce four haploid megaspores. Hence, megaspore is haploid.
•MMC or Megaspore Mother Cell is a diploid cell which develops in the Nucellus of the ovule. MMC undergoes meiotic division to produce four haploid megaspores out of which, only one remains functional and the other three degenerate.
Hence, only MMC is diploid and rest are haploid structures.
So, the correct answer is D.
Multiple choice botany asexual and sexual reproduction in plants structure of male and female reproductive structures structure of ovule gynoecium

The ovule of an angiospherem is technical equivalent to

  1. Megaspore

  2. Megasporangium

  3. Megasporophyll

  4. Megaspore mother cell
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The placentas consists an enlarged basal portion which is called as ovary bearing one or more ovules also called as integumented megasporangium.

So the correct option is 'Megasporangium'.

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

Type of ovule present in Opuntia is

  1. Amphitropous

  2. Campylotropous

  3. Circinotropous

  4. Orthotropous
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation
• Amphitropous ovule- The body of ovule gets curved along with the embryo sac in such a way that it becomes horseshoe-shaped. This type of ovule is found in families like Butamaceae, Loganiaceae.
• Campylotropous ovule- This type of ovule is similar to Anatropous ovule but curvature is less than that of anatropous ovule. Campylotropous ovule is found in families like Chenopodiaceae. 
• Circinotropous ovule- In this type of ovule, the length of funiculus becomes increased and it covers the whole ovule. It is found in families like Cactaceae (Opuntia).
• Orthotropous ovule is the simplest and primitive type of ovule. In this type of ovule, micropyle, chalaza and funiculus lie in one vertical plane. Examples , all gymnosperms, Polygonum.
Hence, Opuntia has circinotropous ovule. So, the correct answer is C.
Multiple choice botany asexual and sexual reproduction in plants structure of male and female reproductive structures structure of ovule gynoecium

In ovule, cuticle is present over

  1. Outer part of integument

  2. Outer part of nucellus

  3. Surface of both nucellus and integuments

  4. None of the above
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation
The cuticle is a waxy substance which fills the space between the Nucellus and inner integument and between the outer and inner integuments of the ovule. Both the integuments are covered with a layer of cuticle.
Hence, the cuticle is present over the outer part of integument.
So, the correct answer is A.
Multiple choice botany asexual and sexual reproduction in plants structure of male and female reproductive structures structure of ovule gynoecium

Which one produces callose for breaking plasmodesmal connections among microspore mother cell?

  1. Microspore mother cells

  2. Sporogenous cells

  3. Tapetum

  4. Middle layers
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation
The process of formation of microspores from spore mother cells (SMC) or Microspore mother cell is called microsporogenesis. Very important changes occur in the Tapetum and locule of the anther during microsporogenesis. In the beginning, when the locule is preparing for microsporogenesis, there are plasmodesmatal connections between Tapetal and Tapetal cells, tapetal and SMC and between SMC and SMC. Very small molecules can pass through these connections. Towards the end of zygotene-pachytene stage of prophase I of meiosis, callose layer starts to get depositing around each SMC and the plasmodesmatal connections are cut off. This callose is contributed by the dictyosomes present in the peripheral cytoplasm of the microspore mother cell.
Hence, Microspore mother cells produces callose for breaking the plasmodesmatal connections among microspore mother cells.
So, the correct answer is A.
Multiple choice botany asexual and sexual reproduction in plants structure of male and female reproductive structures structure of ovule gynoecium

Ovules of Capsella and Pisum sativum are

  1. Orthotropous

  2. Anatropous

  3. Amphitropous

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

• Orthotropous ovule - The simplest and primitive type of ovule. In this type of ovule, micropyle, chalaza, and funiculus lie in one vertical plane. Examples: all gymnosperms, Polygonum.

• Anatropous ovule - The most common type of ovules which occurs in more than 80% of angiosperm families. The body of ovule is rotated by 180° and micropyle comes near to the funiculus. Chalaza and micropyle lie in the straight line but hilum is at 90° to the micropyle.
• Amphitropous ovule - The body of ovule gets curved along with the embryo sac in such a way that it becomes horseshoe-shaped. This type of ovule is found in families like Butamaceae, Loganiaceae.
• Campylotropous ovule - This type of ovule is similar to Anatropous ovule but the curvature is less than that of an anatropous ovule. The campylotropous ovule is found in family Chenopodiaceae and in Pisum and Capsella.
So, the correct answer is D.

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

Tetrad of megaspores is generally

  1. Tetrahedral

  2. Linear

  3. Decussate

  4. Isobilateral
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation
Megaspore mother cell undergoes meiosis to form four haploid megaspores. These megaspores are arranged in the form of a linear tetrad. The megaspore mother cell undergoes first meiotic division and a transverse wall is laid down resulting in the formation of a dyad. The two cells of the dyad similar divides transversely resulting in the formation of a linear tetrad. Tetrahedral, decussate, and isobilateral tetrads are found in case of microspores i.e. such tetrads are formed during microsporogenesis. Hence, tetrad of megaspores is generally linear.
So, the correct answer is B.
Multiple choice botany asexual and sexual reproduction in plants structure of male and female reproductive structures structure of ovule gynoecium

Ovule of Opuntia is

  1. Campylotropus

  2. Amphitropous

  3. Circinotropous

  4. Hemitropous
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation
•Campylotropous ovule- This type of ovule is similar to Anatropous ovule but curvature is less than that of anatropous ovule. Micropyle is near to the funiculus. Chalaza and micropyle lie in the straight line but hilum is at 90° to micropyle. Campylotropous ovule is found in family Chenopodiaceae and in Pisum and Capsella.
•Amphitropous ovule- The body of ovule gets curved along with the embryo sac in such a way that it becomes horseshoe-shaped. This type of ovule is found in families like Butamaceae, Loganiaceae.
•Circinotropous ovule- In this type of ovule, the length of funiculus becomes increased and it covers the whole ovule. It is found in families like Cactaceae (Opuntia).
•Hemianatropous ovule- The body of ovule is turned through 90° and micropyle and chalaza lie in a straight line but funiculus is at right angle or 90° with both these two. E.g. Ranunculaceae.
Since Opuntia has Circinotropous ovule.
So, the correct answer is C.