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.
The general term for carbohydrate monomer is Glucose Polysaccharide Monosaccharide Fructose
<span>There are five environmental factors are used to create an attractive environment is,
competitors, threat of entry, substitutes, suppliers, customers.
These are the main factors that help to determine how attractive or unattractive an environment.</span>
Answer:
blood can still return via the deep veins
Explanation:
The venous system at the leg is known for its complexity and highly branched nature. The superficial and deep veins, both branches and connects with each other at different points along their length
