Plant Growth And Development(11th And 12th > Biology ) Questions and Answers
Explanation:-
Answer: Option C. -> Scarification:
C
Scarification involves weakening, opening, or otherwise altering the coat of a seed to encourage germination. Scarification is often done mechanically, thermally, and chemically. The seeds of many plant species are often impervious to water and gases, thus preventing or delaying germination.
Explanation:-
Answer: Option D. -> Cotton:
D
Short-day plants flower when their day lengths are less than their critical photoperiods. They are unable to flower during long days with extreme amounts of sunlight or when exposed to a great deal of artificial light. These plants require regular periods of darkness to mature and flower, and they typically begin their growth during the summer months but do not flower until fall, when the days are getting shorter. There are many varieties of short-day plants. A lot of them are very important to agriculture and society, like cotton, rice, and sugarcane
Explanation:-
Answer: Option A. -> Differentiation:
A
The cells derived from root apical and shoot-apical meristems and cambium differentiate and mature to perform specific functions. This act leading to maturation is termed as differentiation. During differentiation, cells undergo few to major structural changes both in their cell walls and protoplasm. For example, to form a tracheary element, the cells would lose their protoplasm. They also develops a very strong, elastic, lignocellulosic secondary cell walls, to carry water to long distances even under extreme tension.
Explanation:-
Answer: Option C. -> Both extrinsic and intrinsic factors:
C
Growth and differentiation together is termed as development and in plants it is dependent on both intrinsic and extrinsic factors. The former includes both intracellular (genetic) or intercellular factors (chemicals such as plant growth regulators) while the latter includes light, temperature, water, oxygen, nutrition, etc.
Explanation:-
Answer: Option A. -> Wheat and rye:
A
Vernalisation refers specially to the promotion of flowering by a period of low temperature. It is useful in conversion of winter variety into spring variety by chilling treatment (0.4∘C). Applicable only to temperate plants.
Explanation:-
Answer: Option B. -> Length, area, volume, and cell number:
B
Growth in measured by a variety of parameters like increase in flesh weight, dry weight, length area, volume and cell number. Growth of root and pollen tube is measured in terms of their length, leaf in terms of area, fruit in terms of volume and bacteria in terms of cell number.
Explanation:-
Answer: Option C. -> Gibberellins:
C
Gibberellins were first discovered in rice plants infected with foolish seedling disease or bakane disease by japanese scientist Eiichi Kurosawa in 1926