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.
I'm not entirely sure what you mean, but a fit animal is one that is able to out-compete with other animals in its ecosystem. It possesses some kind of advantage, which makes it easier to compete with others for food, water, shelter, and mates. Due to these qualities, the animal is obviously able to live for a good deal of time and have a greater chance of producing viable offspring.
Ribosomal RNA<span> (rRNA) associates </span>with<span> a set of </span>proteins<span> to form ribosomes. These complex structures, which physically move along an mRNA </span>molecule<span>, catalyze the assembly of amino acids into </span>protein<span> chains. They also bind tRNAs and various accessory </span>molecules<span> necessary for </span>protein<span> synthesis.</span>
Answer:
The answer is true.. it is attached to the carbon backbone.