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Multiple choice chemistry the s-block elements (alkali and alkaline earth metals) biological importance of magnesium and calcium biological importance of elements biological importance of s block elements biological importance of sodium and potassium

Which of the following statements is false ?

  1. ${\text{M}}{{\text{g}}^{{\text{2 + }}}}$ ion form a complex with ATP
  2. ${\text{C}}{{\text{a}}^{{\text{2 + }}}}$ on are important in blood clotting
  3. ${\text{C}}{{\text{a}}^{{\text{2 + }}}}$ ion are not important in maintaining the regular beating of the heart.
  4. ${\text{M}}{{\text{g}}^{{\text{2 + }}}}$ ion are important in the green parts of plants.
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Calcium ions (Ca2+) are crucial for muscle contraction, including the rhythmic contraction of cardiac muscle (heartbeat). Therefore, the statement that they are not important in maintaining the regular beating of the heart is false.

Multiple choice chemistry the s-block elements (alkali and alkaline earth metals) biological importance of magnesium and calcium biological importance of elements biological importance of s block elements biological importance of sodium and potassium

Which  of the following statement is false?

  1. $Mg^{2+}$ ion forms a complex with $ATP$
  2. $Ca^{2+}$ ions are important in blood clothing.
  3. $Ca^{2+}$ ions are not important in maintaining the regular beating of the hear
  4. $Mg^{2+}$ ions are important in the green parts of plants
Reveal answer Fill a bubble to check yourself
C Correct answer
Multiple choice chemistry the s-block elements (alkali and alkaline earth metals) biological importance of magnesium and calcium biological importance of elements biological importance of s block elements biological importance of sodium and potassium

Simple proteins bonded with a non-protein prosthetic group (acting as a cofactor) are called:

  1. Simple proteins

  2. Conjugated proteins

  3. Proteonic proteins

  4. All the above
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Simple proteins bonded with a non-proteinic prosthetic group (acting as cofactor) are called conjugated proteins.
Examples include  Glycoprotein, Lipoprotein, and Phosphoprotein.

Multiple choice chemistry the s-block elements (alkali and alkaline earth metals) biological importance of magnesium and calcium biological importance of elements biological importance of s block elements biological importance of sodium and potassium

Ripening of fruits can be caried out in presence of :

  1. $Na _2SO _4$
  2. $NaCl$
  3. $CaCl _2$
  4. $CaC _2$
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Calcium carbide (CaC2) reacts with moisture to produce acetylene gas, which acts as a synthetic plant hormone to induce fruit ripening.

Multiple choice chemistry the s-block elements (alkali and alkaline earth metals) biological importance of magnesium and calcium biological importance of elements biological importance of s block elements biological importance of sodium and potassium

Which is used for fixing atmospheric nitrogen?

  1. $CaCN _2$ (nitrolim)
  2. $Li _3N$
  3. $Mg _3N _2$

  4. All of these
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

For fixing atmospheric nitrogen -nitrolim is used and further $CaCN _2+C$ is used as fertilizer.

Multiple choice chemistry the s-block elements (alkali and alkaline earth metals) biological importance of magnesium and calcium biological importance of elements biological importance of s block elements biological importance of sodium and potassium

Which one of the following has magnesium?

  1. Vitamin $B _{12}$

  2. Chlorophyll

  3. Haemocyanin

  4. Carbonic anhydrase
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

$Mg$ is present in chlorophyll which is a green pigment and is used in photosynthesis in green plants.

Hence option B is correct.

Multiple choice chemistry the s-block elements (alkali and alkaline earth metals) biological importance of magnesium and calcium biological importance of elements biological importance of s block elements biological importance of sodium and potassium

Ripening of fruits can be carried out in the presence of :

  1. $Na _2SO _4 $
  2. $NaCl$
  3. $CaCl _2$
  4. $CaC _2$
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Calcium carbide is also used for ripening fruit artificially in some countries. When calcium carbide comes in contact with moisture, it produces acetylene gas, which is quite similar in reaction to the natural ripening agent ethylene.

Hence option  D is correct.

Multiple choice chemistry the s-block elements (alkali and alkaline earth metals) biological importance of magnesium and calcium biological importance of elements biological importance of s block elements biological importance of sodium and potassium

State True or False.
Magnesium is an essential constituent of chlorophyll, the green colouring matter of plants.

  1. True

  2. False
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Magnesium is the central metal ion in the porphyrin ring of the chlorophyll molecule, which is essential for photosynthesis.

Multiple choice chemistry the s-block elements (alkali and alkaline earth metals) biological importance of magnesium and calcium biological importance of elements biological importance of s block elements biological importance of sodium and potassium

Nitrolim is a mixture of :

  1. $CaC _2$ and graphite
  2. $CaCN _2$ and graphite
  3. $Ca(CN) _2$ and graphite
  4. $CaCN _2+N _2$
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation
 $CaC _2 +N _2\longrightarrow CaCN _2 +C$

When nitrogen is passed over calcium carbide at a suitable high temperature, we get a mixture of $CaCN _2 + Graphite (C)$ known as nitrolim which is a nitrogenous fertiliser."