InterviewSolution
Saved Bookmarks
InterviewSolution
| 1. |
Which of the following is correct for phosphorus ? (i) it occurs in minerals of the apatite family which are the main components of phosphate rocks. (ii) It is an essential constituent of animals and plant matter (iii) It is present in bones as well as in living cells. (iv) Phospho proteins are present in milk and eggs.A. (i),(ii),(iii)B. (i),(ii),(iii),(iv)C. (ii),(iii),(iv)D. (ii),(iii) |
|
Answer» Correct Answer - 2 Phosphorous is found in phosphate rock, which is mostly calcium phosphate, `Ca_(3)(PO_(4))_2` and in fluorapatite, `Ca_(5)(PO_(4))_(3)F` The apatites are phosphate minerals with the formula `3(Ca^(2+))_(3) (PO_(4)^(3-))_(2),Ca^(2+)(X^(-))_(2)` where `X_(-)` is usually `F^(-), Cl^(-)`, or `OH^(-).` Phosphorus is also important in living systems and is the sixth most aboundant element in the human body. Our bones are mostly `Ca_(3)(PO_(4))_(2)` and tooth enamel is almost pure `Ca_(5)(PO_(4))_(3)`. Phosphate gorups are an integral part of the nucleic acids `DNA` and `RNA` , the molecules that pass genetic information from generation to generation. |
|