Definitely D. Because we just learned about this in science
A robin flying south for the winter
The cholecystokinin generates a satiety or nausea sensation to the brain, quenching the appetite once it has eaten enough, occurs naturally in the human organism in the small intestine, secreted from the cells of the duodenum and jejunum to promotes fats absorption in the digestion process.
All that is slow gastric emptying.
<em>water is important because it gives space to the substances to get in it also it makes the substances wet and dissolve the gases in it ,to transport them from one place to another... </em>
The correct answer is option A, that is, Phylum Porifera.
The species of Phylum Porifera are aquatic, that is, mostly marine. They exhibit cellular grade of the body, they are diploblastic animals with asymmetrical symmetry. They lack body cavity and exhibits a holozoic mode of nutrition with intracellular digestion.
They lack circulatory and nervous system and possess the tendency to regenerate their parts of the body. The organisms in phylum Porifera exhibits both asexual and sexual mode of reproduction.