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The chemical messengers that enter the blood are hormones, and they are carried throughout the body by the circulatory system, specifically the blood vessels. This activity is known as endocrine signaling.
The nervous system stores energy and nutrients in the form of neurotransmitters, which are chemical messengers that help transmit nerve impulses throughout the body. These neurotransmitters are stored in synaptic vesicles located at the ends of nerve cells, ready to be released when a nerve impulse needs to be transmitted.
The chemical messenger is a hormone which are produced by endocrine glands
Hormones are chemical messengers that are built from proteins. These proteins are produced in various glands throughout the body and play important roles in regulating different physiological functions. Examples include insulin, growth hormone, and oxytocin.
It helps the cell by making sure everything gets circulated throughout the cell.
I believe they are called chemical messengers because of their function and the fact it is a chemical. They travel through the blood and target cells respond to hormones often because of their structure. I have read in a science book (McDougal Littell 's Human Biology) that they are called chemical messengers because they are made at one location and function at another.
"hormones"
Lund
Paracrines
Neurotransmitter.
It seems like there might be a misunderstanding. "Covalent" refers to a type of chemical bond, while "blood" is a bodily fluid that transports nutrients and oxygen. There is no such thing as "covalent blood."
Endocrine glands secrete chemical messengers called hormones. These chemicals are secreted directly into the bloodstream, where they are carried by the circulatory system to target tissues throughout the body.