Sponges are sessile animals that have specialized cells called amoebocytes and choanocytes.
Sponges (phylum Porifera) are one of the simpllest multicellular organisms (first to branch off the evolutionary tree from the common ancestor of all animals) that have bodies full of pores and channels allowing water to circulate through them. Sponges’ s structure consists of two thin layers of cells and mesohyl layer between them. They don’ t have real tissues or organ systems such as nervous, digestive or circulatory systems. Constant water flow through their openings and pores obtain food and oxygen and remove wastes.
The statement "The writer always states the hypothesis at the beginning of a scientific paper" is True.
<span>A hypothesis is a supposition made by the scientist. In order for a hypothesis to be a scientific hypothesis, the scientific method requires for it to be tested. If a hypothesis cannot be tested, it cannot be scientific hypothesis. It is important to state the hypothesis clearly at the beginning of a scientific paper. This enables the reader to understand the problem.
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The thyroid gland regulates growth and development through the rate of metabolism.
I think its A, because none of the other options would make sense