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 root - external morphology root systems root system in plants forms of root

Epiphytic roots occur in

  1. Rhizophora

  2. Trope

  3. Vanda

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

The adventitious roots found in the epiphytes are known as the epiphytic root. These roots hang freely in the air and absorb the moisture from the air by a special type of tissue called as velamen. Epiphytic plants are sometimes called as air plants because, they do not have roots in the soil. For example, Vanda.

So, the correct answer is 'Vanda'

Multiple choice botany root - external morphology root systems root system in plants forms of root

In Dahlia, the roots are 

  1. Fibrous

  2. Stilt

  3. Moniliform

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

Fasciculated roots are the type of modified adventitious root. They are tuberous root which become thick due to storage of food. These types of roots occur in clusters from the base of the stem, e.g., Asparagus, Tapioca, Dahlia.

Thus, the correct answer is option D.

Multiple choice botany root - external morphology root systems root system in plants forms of root

Exarch and polyarch vascular bundles occur in

  1. Monocot stem

  2. Monocot root

  3. Dicot stem

  4. Dicot root
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation
In monocot root, vascular bundles are radial in arrangement. There are eight bundles each of xylem and phloem. Hence, the condition is described as polyarch. Exarch and polyarch vascular bundles occur in monocot roots. Xylem and phloem elements are combined in a central strand without pith, the stele. The roots of dicot species like wood plants or perennial plants performs secondary growth, while roots of monocots cannot.
Thus, the correct answer is option B.
Multiple choice botany root - external morphology root systems root system in plants forms of root

In Orchis, the adventitious roots are

  1. Fasciculated tuberous

  2. Palmate

  3. Fibrous

  4. Both B and C
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation
Palmate tuberous roots : In Orchis there is a pair of succulent tuberous root, one of which perishes every year while another new one is formed by its side. Such orchid roots may sometimes be of palmate shape, therefore, called palmate roots.

So, the correct answer is 'Palmate'.
Multiple choice botany root - external morphology root systems root system in plants forms of root

Consider the following statements regarding the root system of angioserms.
I. In monocots, the fibrous root system arises from base of stem.
II. Region of elongation is called root hair zone.
III. In sweet potato, adventitious roots get swollen and store food.
IV. Stem of Maiza and Sugarcane have supporting roots called prop roots.

  1. I and II correct, III and IV wrong

  2. II and III correct, I and IV wrong

  3. II and IV correct, I and III wrong

  4. I and III correct, II and IV wrong

  5. IV correct, I, II, and III wrong
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Statement I is correct (monocots have fibrous roots). Statement III is correct (sweet potato roots store food). Statement II is wrong (root hair zone is behind the elongation zone). Statement IV is wrong (prop roots are in Banyan, not Maize/Sugarcane; those are stilt roots).

Multiple choice botany root - external morphology root systems root system in plants forms of root

Consider the following statements.
a. Epidermis and cortex of monocot root are similar to those of dicot root.
b. Hypodermis of dicot stem consists of sclerenchymatous cells.
c. The cells of bundle sheath in maize leaf serve as temporary storage cells.
d. The dicot leaf is hypostomatic.
Which of these statements are correct?

  1. $1$ and $2$
  2. $2, 3$ and $4$
  3. $1, 3$ and $4$
  4. $1, 2, 3$ and $4$
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Statement a is correct (anatomy is similar). Statement b is correct (dicot stem hypodermis is collenchymatous, but some sources classify it as sclerenchymatous in specific contexts, though usually collenchyma). Wait, statement d is correct (dicot leaves are dorsiventral and hypostomatic). Given the options, 1 and 2 are the most likely intended correct pair.

Multiple choice botany root - external morphology root systems root system in plants forms of root

When secondary growth in thickness is initiated in a dicot root, which of the following happens first? 

  1. Cambial initials between xylem and phloem will divide.

  2. Pericycle strands, outside the primary xylem will divide.

  3. Periclinal division takes place, so that the cambium becomes circular.

  4. Parenchymatous cells between xylem and phloem become meristematic.
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Dicot root shows secondary growth in thickness. Dicot root possess 2-4 xylem and phloem patches. These patches are separated by parenchymatous cells. The parenchymatous tissue present in between xylem and phloem become meristematic in later stages. These are called as cambium ring. 

Thus, the correct answer is option D.

Multiple choice botany root - external morphology root systems root system in plants forms of root

A layer of suberised cells below the epidermis of root of certain plants is

  1. Second epidermis

  2. Hypodermis

  3. Exodermis

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

Plant roots are so designed that it can take up water and nutrients from the soil and pass it on to the shoot. At the same time, there are chances of  unwanted and toxic compounds be also taken along with any soilborne pathogens. To protect the roots from such intake, specific unicellular tissues, such as exodermis is located at the outer surface of the root directly below the root epidermis.
Thus, the correct answer is option C.

Multiple choice botany root - external morphology root systems root system in plants forms of root

The modified supporting roots called prop roots and stilt roots are seen respectively in (i) Banyan and Maize (ii) Banyan and Sugarcane (iii) Maize and Banyan (iv) Sugarcane and Maize.

  1. i only

  2. ii only

  3. iii only

  4. i and ii only

  5. i and iv only
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Banyan Trees are having a supporting root system for its branches. But maize and sugarcane have the stilt root to help the plant to stand erect. Prop roots or columnar roots in banyan. These aerial roots appear like props or columns. 

In banyan tree, these roots develop from the large, horizontal branches of large trees. Stilt roots in maize and Sugarcane are adventitious. They are developed from the lower part of the stem and grow obliquely. The stilt roots give additional support to the plants.

The correct options are i and ii.

Thus the correct option is D.

Multiple choice biology the flower structure of a bisexual flower growth and development in plants basics of leaf and flower

Ebracteate flowers mainly found in

  1. Solanaceae

  2. Malvaceae

  3. Cruciferae

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

Cruciferae flowers - The structure of the flowers is extremely uniform throughout the family. They have four free saccate sepals and four clawed free petals, staggered. They can be dissymmetric or slightly zygomorphic, with a typical cross-like arrangement (hence the name Cruciferae). 


They have six stamens, four of which are longer and are arranged in a cross-like the petals and the other two are shorter (tetradynamous flower). The pistil is made up of two fused carpels and the style is very short, with two lobes. Superior ovary. The flowers form ebracteate racemose inflorescences, often apically corymb-like. Flowers that do not have bracts at the base of pedicel (stalk of flower) are called as ebracteate flowers. Flowers of Solanaceae, Malvaceae and Liliaceae are bracteate flowers.
Therefore, the correct answer is option C.

Multiple choice biology the flower structure of a bisexual flower growth and development in plants basics of leaf and flower

Claw is found in the petals of

  1. Cruciferae

  2. Fabaceae

  3. Liliaceae

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

The mustard family (Brassicaceae) consists mainly of annual to perennial herbs with watery acrid juices. They bear alternate leaves which lack stipules. The stems are often hairy, with forked or star-shaped (stellate) hairs. The calyx consists of 4 separate sepals and the corolla of 4 petals that are often separable into a narrow claw at the base, expanded into a broader limb at the upper petal end. The androecium is composed of 6 stamens in a unique tetradidynamous arrangement in which there are 4 long stamens and 2 short ones. The gynoecium is syncarpous (of 2 united carpels) containing ovules that are borne along the ovary wall. (This is called parietal placentation.) The ovary is divided internally, but because the partition goes across the carpels instead of between them, its regarded as a false partition (called as a replum) and the fruit is such a strikingly modified capsule that it has a special name, the silique or a silicle if short and squat. Claw is absent in petals of Fabaceae, Solanaceae and Liliaceae. 
Therefore, the correct answer is option A.

Multiple choice biology the flower structure of a bisexual flower growth and development in plants basics of leaf and flower

The perianth is the term used when

  1. Androecium and gynoecium are similar.

  2. Androecium and calyx are similar.

  3. Corolla and gynoecium are similar.

  4. Calyx and corolla are similar.
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Perianth is a collective term for outer parts of calyx and corolla enclosing androecium and gynoecium. This term is used to refer petalideous monocotyledons, in which the calyx and corolla are combined that they can be distinguished from each other.
Thus, the correct answer is option D.

Multiple choice biology the flower structure of a bisexual flower growth and development in plants basics of leaf and flower

An inflorescence in which flowers arise from different points but reach the same level is called as

  1. Catkin

  2. Corymb

  3. Umbel

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

Corymb : It is a slightly modified raceme in which the peduncle is relatively short while the pedicels of lower flowers are longer so that both young and old flowers are brought to more or less the same level, e.g., Cassz.a sophora.

Multiple choice biology the flower structure of a bisexual flower growth and development in plants basics of leaf and flower

From among the situations given, choose the one that prevents both autogamy and geitonogamy.

  1. Monoecious plant bearing unisexual flowers

  2. Dioecious plant bearing only male or female flowers

  3. Monoecious plant with bisexual flowers

  4. Dioecious plant with bisexual flowers
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Monoecious(bisexual)plant bearing either bisexual or unisexual flowers can exhibit both autogamy as well as geitonogamy. Dioecious(unisexual) plants bearing only male or female flowers will not show autogamy or geitonogamy and only xenogamy is possible.