Correct Answer: B) 1.08

Correct Answer: B) synthesis and secretion of proteins

Explanation

The question is asking what the presence of extensive amounts of rough endoplasmic reticulum in a cell indicates. The options are: A) synthesis and metabolism of CH₂O₃ , B) synthesis and secretion of proteins (correct), C) synthesis of ATP, and D) contraction. The rough endoplasmic reticulum (RER) is a type of organelle found in eukaryotic cells. It is called rough because it has ribosomes attached to its surface, which gives it a bumpy appearance under a microscope. The ribosomes on the RER are responsible for synthesizing proteins. Therefore, if a cell has extensive amounts of RER, it is an indication that the cell is involved in the synthesis and secretion of proteins, which is option B and is the correct answer. Proteins have many important functions in the cell, including structural support, enzymatic activity, and cell signaling. Some proteins are also secreted from the cell and used by other cells or tissues in the body. Therefore, cells that need to produce large amounts of proteins, such as cells in the pancreas that produce insulin, have extensive amounts of RER. To summarize, the presence of extensive amounts of rough endoplasmic reticulum in a cell indicates that the cell is involved in the synthesis and secretion of proteins, which is option B and is the correct answer.

Correct Answer: A. hierarchical

Correct Answer: B. horizontal integration

Correct Answer: B. encourages the regeneration of grasses

Explanation

When a controlled fire burns through a grassland, it can remove accumulated dead plant material and woody debris, known as thatch. Thatch can hinder the growth of new grass shoots and prevent sunlight and rainwater from reaching the soil surface. By removing the thatch through controlled burning, the fire creates a favorable environment for grass regeneration.

Correct Answer: D. unpresented cheques

Correct Answer: C. as if

Explanation

(a) (i) X - oxygen

Y - sulphur

(ii) I. - S(s) + O\(_{2(g)}\) \(\to\) SO\(_{2(g)}\) (1)

II. - 2SO\(_{2(g)}\) + O\(_{2(g)}\) \(\to\) 2SO\(_{3(g)}\) (2)

III. - SO\(_{3(g)}\) + H\(_2\)SO\(_{4(aq)}\) \(\to\) H\(_2\)S\(_2\)O\(_7\)\(_{(l)}\) (1)

IV. - H\(_2\)S\(_2\)O\(_7\)\(_{(l)}\) + H\(_2\)O\(_{(l)}\) 2H\(_2\)SO\(_{4(aq)}\) (2)

(iii) Vanadium (V) oxide (1)

(iv) It is because the reaction is exothermic

(v) - In bleaching wood pulp, wool silk, hay

- as germicide and fumigant/ disinfectant

- as refrigerant / refrigerating gas/coolant

- as preservative for grains and fruits

- manufacture of H\(_2\)SO\(_4\)

- as a reducing agent in metallurgy

- for dechlorination

(b) From the equation,

2 mol of H\(_2\) reacts with 1 mol of O\(_2\)

hence 40 cm\(^3\) of H\(_2\) would react with 20 cm\(^3\) of O\(_2\)

Volume of unused oxygen = (30 – 20) cm\(^3\)

= 10 cm\(^3\)

(c) (i) CaCO\(_3\) \(\to\) CaO + CO\(_2\)

(ii) CaCO\(_3\) = 40 + 12 + (16 x 3) = 100 g

CaO = 40 + 16 = 56 g

100 g of CaCO\(_3\) \(\to\)&

Correct Answer: D. sea to land

Explanation

A sea breeze describes a wind that blows from the ocean (sea) inland towards land.

Correct Answer: B. x=1 and y=1

Explanation

x + y = 2 --- eqn I

3x - 2y = 1 --- eqn II

Multiply eqn by 2

2x + 2y = 2 --- eqn III

Subtract eqn II from eqnI

5x = 5 => x = 1

Substitute 1 for x in eqn 1

1 + y = 2 => y = 1