Answer:
Prezygotic barriers:
1. Habitat isolation
2. Behavioral isolation
Explanation:
Pre-zygotic barriers are the barriers which do not allow the formation of the zygote in the organisms.
The two mechanisms of the pre-zygotic barriers are the:
1. Habitat isolation: the Flycatchers do not share the same habitat which is also mentioned in the question that they live on different islands.
2. The behavioural isolation: the Flycatchers could have evolved the different mating rituals as a result of which the could not interbreed.
Thus, Habitat isolation and Behavioral isolation are correct.
Answer:
The correct answer is- iodine
Explanation:
Thyroid glands is an important endocrine gland of the body which release hormone called thyroid hormone in the blood. It plays an important role in metabolism, brain development, and function, muscle control, etc.
The active form of thyroxine is triiodothyronine and the formation of thyroid hormone requires the availability of iodine. Four iodine atoms are present in thyroxine and 3 is present in triiodothyronine. Without iodine, they can not be produced.
Therefore iodine is the essential element that is required for the manufacturing of thyroxine and triiodothyronine.
Microorganims are widespread in nature and are beneficial to life, but some can cause serious harm. They can be divided into six major types: bacteria, archaea, fungi, protozoa, algae, and viruses.