Tag: botany

Questions Related to botany

Observe the example given in the box and find out how many of them possess single ovule in each ovary?


Papaya, water melon, wheat, paddy, orchids, and mango 

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

  1. Three

  2. Four

  3. Five

  4. Six

Show answer
Correct Option: A
Explanation:

paddy, mango and wheat possess single ovule in each ovary whereas papaya, watermelon and orchids contain many

A noncellular layer present on the outside of nucellus is
botany asexual and sexual reproduction in plants structure of male and female reproductive structures structure of ovule gynoecium

  1. Integument

  2. Exine

  3. Endostomium

  4. Cuticle

Show answer
Correct Option: D
Explanation:
• The integument is the protective covering of ovule. Integuments may be one or two in number.
• The exine is the outer layer of pollen cell wall. It is chiefly composed of sporopollenin.
• Endostomium, also known as endostome, is the space between the inner Integument and Nucellus.
• Cuticle is a waxy covering which fills the space between the ovary wall and outer integument.
Thus, a non-cellular layer present on the outside of nucellus is Cuticle.
So, the correct answer is D.

A non-nutritive structure is

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

  1. Tapetum

  2. Endosperm

  3. Integument

  4. Palisade parenchyma

Show answer
Correct Option: C
Explanation:
• Tapetum is the innermost layer and completely surrounds the sporogenous tissue. The cells of tapetum have dense cytoplasm and generally more than one nuclei. It nourishes the developing pollen grains.
• Endosperm is the nutritive tissue that nourishes the developing embryo. It is formed from the fusion of male gamete with the diploid secondary nucleus resulting in the formation of a triploid primary endosperm mother cell which then develops into endosperm.
• Integuments are the protective coverings of the megasporangium. 
• Palisade parenchyma is present in the leaves and is the primary site of photosynthesis in plants. Thus, palisade parenchyma has nutritive function.
Hence, among all the options given in the question, integuments is the non-nutritive structure. So, the correct answer is C.

Y- shaped arrangement of xylem vessles is found in

botany internal structure of root, stem and leaf internal structure of monocot stem internal structure of monocots internal structure of stem(dicot and monocot)

  1. monocot stem

  2. dicotstem

  3. monocot root

  4. dicot root

Show answer
Correct Option: A
Explanation:

Xylem comprises of vessels, tracheids, xylem parenchyma, and restricted xylem strands.  the vessel is Y-molded with bigger two round set metaxylem vessels shaping the arms and littler yearly or winding protoxylem vessels, framing the base.

So, the correct option is 'monocot stem'.

The number of growth rings (sum of the rings of spring wood and autumn wood) in the year 2000 is found to be 20. What will be the number of annual rings in 2018?

botany internal structure of root, stem and leaf internal structure of monocot stem internal structure of monocots internal structure of stem(dicot and monocot)

  1. 38

  2. 8

  3. 28

  4. 18

Show answer
Correct Option: A
Explanation:

Every year one spring ring and one autumn rings make one annual ring which is used to estimate the age of the plant.

Hence the number of rings present in 2000=20
Therefore, the number of rings present in 2018=20+18
That is equal to 38 rings after 18 years.
So the correct option is '38'

Read the following statements and select the correct  option.
A. Damage to chordae tending of semilunar valves in aorta causes back flow of blood in left ventricle.
B. Closure of atrio-ventricular valves during ventricular systole generates first heart sound

botany internal structure of root, stem and leaf internal structure of monocot stem internal structure of monocots internal structure of stem(dicot and monocot)

  1. Both statements are correct

  2. Only statement B is correct

  3. Only statement A is correct

  4. Both statements are incorrect.

Show answer
Correct Option: A
Explanation:

The semilunar valves are present inbetween the aorta and the left ventricle (aortic semilunar valve) and between the right ventricle and the pulmonary artery (pulmonary semilunar valve). The aortic semilunar valve functions to pevent backflow of blood into the ventricle. Damage to chordae tendinae of the aortic semilunar valve will therefore cause backflow of blood to the left ventricle. The first heart sound is produced by the closure of the mitral and the tricuspid valve, that are the atrioventricular valves. 

So, the correct option is 'Both statements are correct'.

In a monocot stem, the vascular bundles are?

botany internal structure of root, stem and leaf internal structure of monocot stem internal structure of monocots internal structure of stem(dicot and monocot)

  1. Arranged in a ring

  2. Arranged alternatively

  3. Present inside endodermis

  4. Scattered in ground tissue

Show answer
Correct Option: D
Explanation:
In a monocot stem, a large number of vascular bundles lie scattered throughout the ground tissue and peripheral bundles are generally smaller than the centrally located ones. The vascular bundles are conjoint, collateral but closed.

So, the correct answer is 'Scattered in ground tissue'.

In monocot stem


(a) Vascular bundles are scattered.
(b) Hypodermis is sclerenchymatous.
(c) Endodermis is well developed.
(d) Stele is atactostele.

botany internal structure of root, stem and leaf internal structure of monocot stem internal structure of monocots internal structure of stem(dicot and monocot)

  1. Only (a) and (b), (d) are correct

  2. Only (c) and (d) are correct

  3. Only (b) is incorrect

  4. All (a),(b),(c) and (d) are correct

Show answer
Correct Option: A
Explanation:

Vascular tissue system composed of vascular bundles and they are scattered. So, the steles are called atactostele. Hypodermis is multilayered and sclerenchymatous. Endodermis is not developed.

So, the correct option is 'a, b, d are correct'.

Select the mismatched pair.

botany internal structure of root, stem and leaf internal structure of monocot stem internal structure of monocots internal structure of stem(dicot and monocot)

  1. Collateral and open vascular bundles- Sunflower stem

  2. Bicollateral vascular bundles - Maize stem

  3. Concentric vascular bundles - Ferns

  4. Radial vascular bundle - Maize root

Show answer
Correct Option: B
Explanation:
A. Collateral open vascular bundles- Xylem is present in the inner side and phloem to the outside and cambium ring is present in between them.
Eg- in dicot stems as in sunflower stem.
B. Bicollateral vascular bundles- one patch of xylem and two patches of cambium are present.
Eg- plants belonging to the family Cucurbitaceae, Solanaceae etc
Mazie belongs to the family Gramineae.
C. Concentric vascular bundles- in which either the xylem or phloem surrounds each other.
Eg- ferns.
D. Radial vascular bundle- Xylem and phloem occupy different radii and alternate each other.
Eg- Dicot and monocot roots (as in maize root).
So, the correct answer is 'Bicollateral vascular bundles - Maize stem'.

Plants have evolved various defences to lessen the impact of predation by herbivores. Choose the correct option for the defence measures in the given plants. Where M-Morphological, C-Chemical, A-Anatomical, P-Physiological.

Acacia Cactus Calotropins
$(1)$ P P M
$(2)$ A M C
$(3)$ P C C
$(4)$ M M C
botany internal structure of root, stem and leaf internal structure of monocot stem internal structure of monocots internal structure of stem(dicot and monocot)

  1. A

  2. B

  3. C

  4. D

Show answer
Correct Option: A