Answers
Some provide nutrients for each other
Explanation:
Answer:
The correct answer is option B. It bind to a receptor in the plasma membrane.
Explanation:
Hormones can be aminoacid based hormones (peptide or amine) or the steroid base hormones on the basis of their nature. Amino acid based proteins are molecules that are proteins,
Peptide hormones are the protein or peptide molecule that release in blood by the exocytosis in the form of preprohormones that mature later and bind to the receptor present on the surface of the plasma membrane of the target cell. The binding of the peptide hormone to the receptors a secondary messenger shows up in the cytoplasm.
Thus, the correct answer is option B. It binds to a receptor in the plasma membrane.
Answer:
At the base of Actinopterygii
*This is a unique characteristic of this group.
Explanation:
A peculiar characteristic organ observed in ray-finned fish (as well as in Sarcopterygii, or lobe-finned fish) but not in cartilaginous fish like shark is the swim bladder.
This organ is often described to be a sac containing gas. It helps these set of fish adjust its buoyancy and its position in the water by regulating the concentration of gas present in it.
The swim bladder is formed as a pouch coming off the embryonic digestive tract, and in chondrosteans and holosteans, with a set of teleosts e.g. the eels, it maintains an open pathway to the esophagus. In majority of the bony fish, the swim bladder is totally sealed off, as gas levels in their swim bladder are regulated by producing gas into the bladder via a network of capillaries, the rete mirabile (Latin word for "marvelous net").
The swim bladder is homologous to the lungs of tetrapods. Since they are formed in the same vein. Few fishes that have an open swim bladder employs it as a breathing organ.
