The correct answer is an accumulation of microorganisms in deep marine environments.
Chalk rock refers to a pure form of limestone produced in tropical and warm seas about 100 million years ago in the Cretaceous period. The microscopic marine algae known as coccoliths thrived in the ancient seas. Their shells were comprised of calcite. With the death of the algae, their bodies sunk to the floor of the sea and sediment of chalk got deposited.
Over many years layers of chalk sediment got deposited and resulted in compaction of loose sediment into solid chalk rock.
Answer:
As the spies of a cactus are modified leaves, they have ar spaces.
Explanation:
However, leaves of cactus are not like every other leaf. These leaves are in the form of spines to save the amount of water that the cactus needs.
Most of the amount of water, cactus s saving in its root. Also, the stem of a cactus is used for making food, and this is also the way of saving the water.
The two main types of fermentation are alcoholic fermentation and lactic acid fermentation. In an alcoholic fermentation, the main product of this process is ethyl alcohol. Lactic acid on the other hand has lactic acid as its main product. When muscle cells run out of oxygen, lactic acid fermentation would commonly take place.<span> </span>
<span>Each type of organic molecule has its own specific type of functional group. Functional groups in biological molecules play an important role in the formation of molecules like DNA, proteins, carbohydrates, and lipids. Functional groups include: hydroxyl, methyl, carbonyl, carboxyl, amino, phosphate, and sulfhydryl.</span>
DNA??? I’m not sure but I’m saying DNA hope I helped!