Biology

[equalsmcsquared.livejournal.com]

Greetings, everyone. Please stack your reports next to the roll sheet. Help yourselves to the snack, God knows I won't eat them all.

Today, we will begin discussing human endocrinology.

The essence of multicellularity is the coordinated interaction of the various kinds of cells that make up the body. Cells communicate with each other by chemical signals.

Three kinds of chemical signaling can be distinguished:

autocrine - the cell signals itself through a chemical that it synthesizes and then responds to. Autocrine signaling can occur solely within the cytoplasm of the cell or by a secreted chemical interacting with receptors on the surface of the same cell

paracrine - chemical signals that diffuse into the area and interact with receptors on nearby cells.
Examples are:
The release of cytokines that cause an inflammatory response in the area.
The release of neurotransmitters at synapses in the nervous system.

endocrine - the chemicals are secreted into the blood and carried by blood and tissue fluids to the cells they act upon.

Comments

Re: After class

[bluemanoncampus.livejournal.com]

Hank looks embarrased, but replies, "As you may be aware, I was abducted by Locker 327 sometime shortly after returning from the body farm trip. I spent several months in an alternate dimension without writing materials of any kind and I honestly don't remember many specifics about the body farm itself.

"However, I did have occasional use for the information on decomposition rates that you taught us at the farm and I can present a paper on those experiences, if you are amenable."

Re: After class

[equalsmcsquared.livejournal.com]

*After a pause, she mutters rather nasty curses in a host of languages.* Of course that is acceptable. I'm just glad you're all right.

Re: After class

[bluemanoncampus.livejournal.com]

Hank grins as he recognizes a few of the curses.

"Thank you, Ms. Sidle. I'll have it ready by next class period. I also appreciate your concern, but all things have a purpose, do they not? The purpose may be inexplicable or inimical to oneself, but it still exists."