Answer:
The correct answer is option (D) "His- strain grows on an his- plate".
Explanation:
The Ames test is a procedure that allows to detect if a given compound can cause mutations on a tested organism by growing strains of bacteria that require histidine (His-) to growth, since they are not able to produce its own histidine. In the Ames test, the bacteria is exposed to a given compound and is grown in a medium with small amount of histidine (his- plate). If the His- strain grows on a his- plate, it means that the bacteria has mutated to synthesize its own histidine and it is considered as a positive result on a the Ames test.
the answer to your question is false
Answer:a positive feedback
Explanation: positive feedback is a type of feedback mechanism employed by the body,in which an output is enhanced or acclerated.
In contrast to negative feedback where the body regulates it's internal conditions by reducing the effect of a stimuli,In positive feedback ,the body enhances the effect of the stimuli.
It is not common as negative feedback in homeostasis.
An example is the increasing release of oxytocin to promote contractions during childbirth,until the child is born.
Another example is the accumulation of blood platelet , in the site of blood vessels injury to
cause blood clotting.
Answer:
Magma is less dense than the surrounding rock which causes it to rise. When magma reaches the surface it is then called lava and the eruptions of lava and ash produce volcanoes. The lava that reaches the Earth's surface will harden and become igneous rock.
Explanation: