Answer:
A, a prokaryotic cell
Explanation:
Prokaryotes are organisms whose cells lack a nucleus and other organelles. Prokaryotes are divided into two distinct groups: the bacteria and the archaea, which scientists believe have unique evolutionary lineages.
Ans.
Lac (lactose) operon in a type of bacterial operon, which shows a cluster of genes that are regulated by a single promoter. It is composed of an operator, promoter, a terminator, and three structural genes (lacA, lacY, and lacZ), which are responsible for the transport and breakdown of lactose.
The lac operon is an inducible operon as it gets activated in the presence of lactose and expressed its functional genes in the form of proteins (or enzymes) for lactose metabolism.
Thus, the correct answer to be fill in first blank is 'inducible' and in second blank is 'lactose.'
Answer:
Foods are ingested by the mouth where they are chewed by the teeth and savored by the taste buds present in the tongue. In the mouth, saliva breaks down food into substances that are easier to digest. Subsequently, the pharynx allows food to be swallowed and it pushes the food into the esophagus, the contractions of the esophageal muscle allow the movement of the food through the esophagus and to the stomach where the food is mixed with the juices and are mostly digested. In the stomach nutrients are absorbed. There are particles that are not absorb and they pass to the intestine where other nutrients are transported to the blood, then pass to the large interstinum where there is water absorption and stool formation that are expelled through the rectum.
Answer:
The earliest known life-forms on Earth are putative fossilized microorganisms, found in hydrothermal vent precipitates, that may have lived as early as 4.28 billion years ago, relatively soon after the oceans formed 4.41 billion years ago, and not long after the formation of the Earth 4.54 billion years ago.
Explanation:
