Answer:
Rock
Explanation:
Minerals are inorganic substances that occur naturally in nature and have a
a definite chemical composition and a crystalline structure while rocks may consists of one or many minerals together along with some organic remains due to which it may not look shiny and crystalline from outside.
Here, the two characteristics that enable the reader to identify the object given by grandmother to Emily as rock are –
a) Looks ugly on the outside (shows the presence of organic matter)
b) solid purple color with pretty crystals (crystalline structure inside)
Answer:
A- A pH change can cause the enzyme to change its shape
Explanation:
A rise or fall in the pH of the medium from the optimum of pH 7 usually affect the enzymes' active sites of and therefore the shape and the rate of enzyme activity.
Assuming the pH is too low, the enzyme medium becomes acidic;Acidosis. The high Hydrogen ions concentration interacts with the R-groups of the amino acids moiety of the enzymes, this interaction affects the ionization of the R-groups, disrupting the ionic bonding holding these R-groups in shape.
This results in loss of the 3-Dimensional shape arrangements of the protein molecule and therefore of the active sites. Since active sites of enzymes determines the specificity of the <u>enzymes substrate- complex </u> to give <u>enzyme-product complex,</u> the catalytic activity of the enzymes decreases, <u>the rate of reaction decreases,and products formation stops, and the reaction also stops.</u>
The same is applicable to extremely high pH=Alkalosis.
However, the effective buffer system of the body prevents this scenarios from happening in real sense in the body. Through mopping by the haemoglobin, excretion by the kidney, etc
They are the same density.
