Photoreceptors<span>: The light sensing nerve cells (rods and cones) </span>located<span> in the retina. Pupil: The adjustable opening at the center of the iris through which light enters the</span>eye<span>. Retina: The light sensitive layer of tissue that lines the back of the </span>eye<span>.</span>
Answer:
The TATA box is an alternating sequence of Adenine and Guanine nucleotides that transcription factors bind to. The TATA box is found just before a gene. The transcription factors tell the RNA polymerase where to bind to begin transcription. This ensures the RNA polymerase will know where to start and which gene to transcribe.
Explanation:
Dominate and no know preditors <span />
In geology, a key bed (syn marker bed) is a relatively thin layer of sedimentary
rock that is readily recognized on the basis of either its distinct
physical characteristics or fossil content and can be mapped over a very
large geographic area.[1]
As a result, a key bed is useful for correlating sequences of
sedimentary rocks over a large area. Typically, key beds were created as
the result of either instantaneous events or (geologically speaking)
very short episodes of the widespread deposition of a specific types of sediment. As the result, key beds often can be used for both mapping and correlating sedimentary rocks and dating them. Volcanic ash beds ( and bentonite beds) and impact spherule beds, and specific megaturbidites
are types of key beds created by instantaneous events. The widespread
accumulation of distinctive sediments over a geologically short period
of time have created key beds in the form of peat beds, coal beds, shell beds, marine bands, black in cyclothems, and oil shales. A well-known example of a key bed is the global layer of iridium-rich impact ejecta that marks the Cretaceous–Paleogene boundary (K–T boundary). Please let me know if it works.
