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

Which of the following statements is/are false?

a. In dicotyledonous plants and gymnosperms, the lateral meristems appear very early in life. b. Plant growth is accompanied by both anabolic and catabolic processes. c. The ability of plants for unlimited growth throughout life is due to the presence of meristems at certain locations in their body.

  1. Only a

  2. Only a and b

  3. Only b

  4. Only b and c

  5. Only c
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

This is the correct option as this statement is false.

Multiple choice

Crossing over takes place at a stage between

  1. leptotene and diplotene

  2. pachytene and diplotene

  3. zygotene and diplotene

  4. zygotene and pachytene
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Crossing over takes place at a stage between zygotene and diplotene. Crossing over is the exchange of genes between two chromosomes, resulting in non-identical chromatids that comprise the genetic material of gametes (sperm and eggs).

Multiple choice

When genotype of haploid pollen and diploid pistil determine incompatibility, it is known as

  1. gametophytic self-incompatibility

  2. sporophytic self-incompatibility

  3. heteromorphic self-incompatibility

  4. homomorphic self-incompatibility
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Gametophytic self-incompatibility is determined by the haploid genotype of the pollen (gametophyte), whereas sporophytic incompatibility is determined by the diploid genotype of the parent plant (sporophyte). In gametophytic systems, the pollen's own genes control compatibility.

Multiple choice

Which one of the following is the carrier of cytoplasmic male sterility factors in crop plants?

  1. Nuclear DNA

  2. RNA

  3. Chloroplast DNA

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

Cytoplasmic male sterility (CMS) is a maternally inherited trait where plants fail to produce functional pollen. The genetic factors responsible for CMS are located in the mitochondrial DNA, not nuclear DNA or chloroplast DNA. Mitochondrial rearrangements or novel chimeric genes interfere with normal pollen development, making this the basis for hybrid seed production in many crops.

Multiple choice

The plastid only

  1. It serves as a conduit for nutrients and growth factors from the material tissue to the embryo

  2. It is highly polyploidy and polytene

  3. It persists even during postembryonic phase

  4. It begins to senesce at torpedo stage of embryo
Reveal answer Fill a bubble to check yourself
D Correct answer
Multiple choice

Which one of the following statements is correct?

  1. In the wood of dicots, ray tracheids are absent.

  2. In the wood of gymnosperms, ray parenchyma is absent.

  3. In most commercially important dicot woods, fibres are absent.

  4. In the wood of all gymnosperms, vessels are absent.
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Vessels are a characteristic feature of angiosperm wood and are completely absent in all gymnosperms (including all conifers). Ray tracheids (A false) are present in some dicots. Ray parenchyma (B false) is present in gymnosperms. Fibres (C false) are abundant and important in dicot woods.

Multiple choice

A concentric vascular bundle that has the phloem surrounding the xylem is called

  1. closed

  2. amphivasal

  3. amphicribal

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

In a concentric vascular bundle, amphicribal arrangement has phloem surrounding the xylem on all sides. Amphivasal (B) is the reverse - xylem surrounds phloem. Radial (D) refers to arrangement in a cylinder. Closed (A) refers to lack of cambium, not tissue arrangement.

Multiple choice

Which one of the following types of inflorescence is found in carrot?

  1. Catkin

  2. Corymb

  3. Spike

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

Carrot (Daucus carota) has an umbel inflorescence - flat-topped with flower stalks arising from a common point like umbrella ribs. Catkin is a hanging spike (oak, willow). Corymb is flat-topped but outer flowers have longer stalks. Spike has flowers directly on the main axis without stalks.