46. Vegetative reproduction is the process by which plant is able to reproduce through its special vegetative parts like
leaves, bulb, Rhizome, stem, root, etc.
Advantages of vegetative reproduction:-
i. New plants need not always grow from seeds and thus, many more plants can be produced commercially than
would occur naturally.
ii. New plants having the same desired characteristics of mother plant can be obtained.
iii. Desired features of more than one plant can be introduced into a single plant through grafting.
47. a. Advantages: It gives the gene which are multitude of features and the genes have a larger chance of survival if a
disease hits. Disadvantages: Cross pollination is slower when compared to self pollination and The natural process
of pollination becomes delayed in this case.
b. Advantages of self pollination include less chance of failure of pollination and maintaining purity of race.
Disadvantages of self pollination include new species are not produced. Another disadvantage is that
weaker progeny happens with continuous self pollination.
45. The combination of the following 3 factors can lead to a massive decline in pollinators population, such that: pesticides and fungicides, pathogens and parasites. But the most dangerous factor seems to be neonicotinoids, which is the most used type of insecticide.
The neonicotinoids insecticide affects the skill of bees to come back to their hives. The neonicotinoids are the next generation of insecticides that do not have adverse effects on human health but they affect the nervous system of insects. Since neonicotinoids are systemic pesticides, hence, the bees can be affected by the nectar or pollen of the plants.
46. The vegetative propagation represents the ability of a plant to asexually reproduce itself, such that one existing plant creates a new offspring, without sexual reproduction.
The specialists in fields such agriculture and horticulture developed techniques using this ability of plants, such that: rooting of cuttings (cutting are parts of plant that usually have leaves), grafting (2 plants are used to create a new plant with the traits of both plants: the above ground part of a plant, called scion, is attached to the rooted part of the 2nd plant, called stock) and other important techniques. One important aspect of vegetative propagation techniques is that it allows the economically reproduction of important and useful species of plants without the use of seeds. Other important aspect is the development of new and improved horticultural varieties of plants.
Possible answer for Image 1 is only given.
41. a. Phytoremediation
b. Phytoremediation uses plants or algae to remove contaminants from soils, sediments or water into harvestable
42. a. Angiosperm
Reason:- Parallel leaf venation, Presence of cotyledons, Thick and hard stem
b. It came from desert.
Reason:- Narrow leaves to reduce water loss, thick stem in waxy epidermis