Answer: B. Closed
In a closed circulatory system is the one in which the blood is circulated to all the parts of the body of the organism through vessels of different length and width. In this system the blood is pumped from the heart through blood vessels where it is transported to different organs and cells of the body instead of filling up the body cavity.
The
correct answer is they filter urea from blood and produce urine.
<span>
Nitrogenous
wastes tend to form toxic ammonia which needs to be removed. Terrestrial
animals must detoxify ammonia by converting it into a relatively nontoxic molecule-urea
(it occurs in the urea cycle). The urea cycle mainly occurs in the liver and the
produced urea is then released into the blood. It travels to the kidneys where
is filtrated and excreted in urine.</span>
The word 'clone' is derived from the greek term 'klon', or 'twig', referring to the fact that twigs have the capabilities to grow entire new plants.
