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The meaning of Sacha Sauda is pious deal or in other words a true kind of business. Guru Nanak Dev Ji made a pious deal by spending twenty rupees to feed the saints.

Guru Nanak Dev’s father gave him twenty rupees to start some business. Guru Nanak Dev Ji spent that money in feeding the hungry saints and this incident is famous as ‘Sacha Sauda’.

Correct option is (d) Soybean

1. The plants which do not require specific duration of light period or dark period flowering are day neutral plants (DNP). 

2. They flower throughout the year, as they do not need specific photoperiod. 

3. The flowering in these plants is independent of photoperiod. 

4. Examples – cucumber, tomato, cotton, sunflower, maize and balsam.

Correct option is (b) dark/night

Correct answer is (a) lag phase

Sperms reach the penis along with the fluid produced by accessory glands and they are secreted to outside. Secretions provide a medium for the movement of sperms and nourishment

The plants which flower when the day length or light period is shorter than the critical photoperiod are called short day plants or SDP 

SDPs usually flower during winter and late summer. 

Examples – Dahlia, Aster, Tobacco, Chrysanthemum, Soybean (Glycine max) and Cocklebur (Xanthium).

Correct answer is (a) SDP

It is a proteinaceous pigment present in leaves which perceives stimulus of light for flowering. As it is interconvertible in two forms, it promotes flowering in SDP and inhibits flowering in LDE.

Correct answer is (d) apical bud (shoot apex)

A low temperature or chilling treatment that induces early flowering in plants is known as vernalization.

Significance: 

1. Due to chilling treatment crops can be produced earlier. 

2. Crops can be grown in areas where they do not grow naturally.

The response of plant to the influence of low temperature on flowering in plants is called vernalization.

It is response of flowering to low temperature treatment which helps in cultivation of crops in regions where they do not occur naturally and also crops can be produced earlier.

1. Plants require inorganic materials for the synthesis of food. 

2. These elements are obtained by plants in the form of minerals mainly form soil. 

3. Chemical analysis of plant ash reveals that about 40 different minerals are needed by plants which are taken from surroundings, (air, soil and water) 

4. These minerals are absorbed in dissolved form, i.e. ionic form through root system mainly root hairs. 

5. Some minerals are required in large amounts (major) while some are needed only in traces or small amounts (minor).

Oxygen and fluorine have small size and high electronegativity, so they can easily oxidise the metal to its highest oxidation state.

1. Micronutrients are required in minute quantities by plants. 

2. Their moderate decrease causes deficiency symptoms while their moderate increase causes toxicity. 

3. The reduction in dry weight of a tissue by 10% by any mineral is known as toxicity. 

4. It is not easy to identify toxicity symptoms. 

5. Most of the time, the excess of an element inhibits the uptake of another element resulting in causing the deficiency symptom of that element. 

6. Manganese inhibits calcium translocation towards apex of stem and exhibits symptoms of chlorosis with grey spots appearing on leaves.

7. This is because manganese competes with iron and magnesium for uptake. 

8. Therefore what we see as symptoms of manganese toxicity, may be the deficiency symptoms of Fe, Mg and Ca.

The only gaseous plant hormone is Ethylene.

1. Yes.

2. Due to very high electronegativity and small size oxygen and fluorine can oxidise the metal to its highest oxidation state.

Correct answer is (b) C, H, O

The maximum oxidation state shown by Mn in its compounds is + 7

Correct answer is (a) 1 to 6°C

Correct answer is (b) Phytochrome

Acidic, amphoteric and basic

In pea seeds germination is hastened by the presence of light. Light inhibits germination of the seeds of onion.

When fruits develop without fertilization as in banana the seeds become abortive and the fruit naturally seedless.

These cells are metabolically active hence show high rate of respiration. 

Cytokinin is the plant hormone that can delay senescence.

Senescence is the process by which cells irreversibly stop dividing and enter a state of permanent growth arrest without under-going cell death.

Abscisic acid.

Parthenocarpic fruits develop without fertilization, hence the seeds are abortive and become seedless.

Axillary buds of many plants are normally suppressed because of apical dominance of the terminal bud.

Ethylene hormone

The Richmond-Lang effect is the delay in the process of ageing by application of cytokinins.

Application of cytokinin delays the process of aging by nutrient mobilization. It is known as Richmond Lang effect.

Flies are attracted by the presence of ethylene.

Commercial applications of NAA:

• Induce flowering in pineapple.
• Root setting hormone.
• Natural fruit setting in some species.

It is principle of apical dominance where in lateral buds start growing after removal of apical buds resulting in bushy growth of plants. 

• Fruit setting: IBA is used to improve fruit setting in trees.
• Root formation: IBA is used to induce rapid root formation in cuttings.

Indole Butyric Acid

2,4,5-Trichlorophenoxy acetic acid. It used as a selective weedicide.

Correct answer is (c) Mevalonic acid

Abscissic acid causes the suppression of axillary birds which fail to grow creating a condition of dormancy, hence called dormin.

(a) The water molecules which form part of the structure of a crystal are called water of crystallization.

Example: CuSO₄ .5H₂O

(b) The blue copper sulphate crystals contain water of crystallization as it is blue in colour.

(c) Anhydrous copper sulphate turns blue on adding water. This property of anhydrous copper sulphate is used to detect the presence of moisture in a liquid.

Growth is a permanent irreversible change brought about by increase in height, weight or volume. The three phases of growth are;

(a) Phase of cell division or cell formation: This region is located at the tip of shoot and root. It is represented by the apical meristem capable of rapid cell division. The cells are undifferentiated, with a thin cell wall made of cellulose, with an active protoplasm and prominent nucleus. This region is mainly concerned with cell division.

(b) Phase of cell elongation or cell enlargement:

This region lies next to the cell formation zone. The cells enlarge because of their elastic cell walls. Growth takes place during this stage either by apposition or intusucception. Cells are turgid.

(c) Phase of cell differentiation or cell maturation:

This represents the last region and differentiation based on functions is seen here. Secondary walls are laid down where some have additional deposits of lignin, Suberin and others lose their protoplast and become dead.

Uses of plant hormones:

(a) Auxins show apical dominance

 As long as the apical bud is present it prevents the growth of lateral buds. This is used in the long term storage of potato tubers.

(b) Auxins control abscission:

This is a process by which leaves and fruits drop from a tree by the formation of the abscission. Increase in auxin concentration prevents the formation of this layer and is used to prevent defoliation of leaves in cabbage and cauliflower.

(c) Gibberellins show Bolting:

This results in an elongation of stem and used to induce flowering in Cabbage and Cauliflower. A genetically dwarf plant is converted to a tall by % this process.

(d) Gibberellins break dormancy and help in promoting seed germination by sythesising a-amylase.

Define growth: growth is a permanent irreversible change brought about by an increase in height, weight or volume. Growth curve is a plot of the increase in the height, weight or volume of a plant or its parts against time. In the initial stages, growth is slow and is represented by the lag phase followed by a sudden phase of rapid growth called log phase or exponential growth.

The total time during which growth increase is called the grand period of growth a term used by Julius Sachs. This is followed by a decreasing growth rate where a decline in growth is seen and the point at which it occurs is called inflexion point. After this, the growth stops and is called the steady-state or the stationary phase. This portion depends upon the type of plant. The shape of the graph is ‘S’ shaped, so-called the sigmoid growth curve.

(i) Growth rate refers to the expression of increased growth per unit time. 

(ii) It can be arithmetic or geometric increase. 

(iii) In arithmetic growth, following mitotic cell division only one daughter cell continues to divide while the other differentiates and mature. 

(iv) The simplest expression of arithmetic growth is exemplified by a root elongating at a constant rate. 

(v) On plotting length of the organ at different times a linear curve is obtained.

It is expressed as:

L_t = L₀ + rt

Here, 

L_t = Length at time 't'

L₀ = Length of time Zero

r = growth rate per unit time.

(vi) In geometrical growth, the initial growth is slow (lag phase) and rapidly at an exponential rate (log or exponential phase). 

(vii) In this growth, both the progeny cells formed by mitotic cell division retain the ability to divide and continue to do so. 

(viii) However, with limited nutrient supply, the growth slows down (stationary phase). 

(ix) If we plot a parameter of growth against time, we get a typical S-shaped or sigmoid curve. 

(x) The exponential growth can be expressed as:

W₁ = W₀e^rt

Here, W₁ = final size (Weight, height, number etc.) 

W₀ = initial size 

r = growth rate 

t = time of growth 

e = base of natural logarithms.