Saturday, February 2, 2013

LMAYQ: Let me do your homework for you

Sometimes reading the textbook is just too hard. And sometimes it's much easier just to type your exact homework question into a search engine and find the answer. Before we get started you might want to take a look at Smith and Wren (2010) "What is Plagiarism and how can I avoid it?" 

This edition of Let Me Answer Your Questions will address 'homework questions.' As always, you can find previous LMAYQ questions here.

Tough Homework Questions are for the Internet (source)

1. "cells that fire together a) wire together. b) definitely don’t wire together. c) become overheated and die. d) wire with inactive cells."

Ok, student. If you have to turn to the Internet for this multiple choice question, you need a serious lesson in test-taking skills. Here's a tip. If you don't know the answer, eliminate some because they are obviously not the right answer. A good rule to follow is if it says definitely or all or always in the answer it is unlikely that that is the right one. So we can eliminate B. If you know anything about neurons from your class, you should at least know that neurons fire. If they didn't fire they wouldn't 'work'. So you can eliminate C. If all the cells that fired together overheated and died, you would basically not have any neurons left in your brain after reading this sentence. Now you have a 50-50 chance of guessing it correctly. Not too bad. But seriously, if one answer creates a cute little rhyme with the question... it's probably going to be that one. So yes, neurons that fire together wire together.

2. "explain simply where the hippocampus is"

The hippocampus is one of the most famous brain structures because it has to do with encoding new memories. It's name comes from the Greek hippo (horse) and campus (sea), because it looks like a seahorse:
Hippocampus = Seahorse (source)
(By the way, potamus=river, so a hippopotamus is a 'river-horse'). Back to the hippocampus: It is a structure in the brain and it is located subcortically meaning under the cortex. Specifically it's located under the temporal lobe of the cortex. There are two of them, one on each side of brain.

3. "Why are neurons and blood cells structured and shaped differently from each other?"

Neuron and Blood cell Knitting (by Estonia76)
This is a great question, but it has the ring of 'I need help with my homework' about it. I talk a lot about the shapes of neurons in this blog, usually speculating on why different neurons would be shaped differently from each other. But this is a good question, why do neurons have dendrites and axons in the first place?
Well basically neurons need to receive and transfer information, while blood cells need to physically move to transfer oxygen. Neurons stay in place, while blood cells travel all over the body. Blood cells need to be small and hydrodynamic to float through your blood vessels. Neurons need to 'cover space' to contact many other neurons, so they have branching dendrites and axons.

© TheCellularScale

ResearchBlogging.orgSmith N Jr, & Wren KR (2010). Ethical and legal aspects part 2: plagiarism--"what is it and how do I avoid it?". Journal of perianesthesia nursing : official journal of the American Society of PeriAnesthesia Nurses / American Society of PeriAnesthesia Nurses, 25 (5), 327-30 PMID: 20875892


  1. I have a question (assuming this is a good place to ask it...). It's not a homework question, I've just been reading up on this stuff on my own time and I am curious. Are there any known transmitters in the NS that activate both inhibitory receptor subtypes AND excitatory receptor subtypes? Or does every known transmitter activate EITHER a bunch of excitatory subtypes OR a bunch of inhibitory subtypes?

    If there aren't any transmitters like this, why do you think this is? Intuitively it seems to me that it would be a useful mechanism for producing certain complex behaviors that might require simultaneous excitation of some brain areas and inhibition of other brain areas. Am I way off base in thinking that?

  2. Great question, anonymous. In general there is a pretty clear divide between excitatory (glutamate) and inhibitory (GABA) neurotransmitters, but of course that's not the whole story. Sometimes GABA can act excitatory. I'll write a post about this (maybe today), because it's a little complicated.
    What you really might be interested in is the "neuromodulator" types on neurotransmitter, like dopamine. Those are neither inhibitory nor excitatory in the classic sense, but they modulate the way information gets communicated in a system.