Essential Biology Learning Guides (homework, review)
Topic 6.5 Nerves, Hormones and Homeostasis
Topic E.4/E.5, Neurotransmitters, Synapses and the Human Brain
Topic E.1/E.2, Stimulus, Response and Perception
Topic E.3/E.6, Innate/Learned Behavior, Further Behavior
Topic E.4/E.5, Neurotransmitters, Synapses and the Human Brain
Topic E.1/E.2, Stimulus, Response and Perception
Topic E.3/E.6, Innate/Learned Behavior, Further Behavior
Support material for unit (homework, class discussion)
Powerpoint (S Taylor) for topic 6.5 Clegg reading: pp. 210-224, in textbook, not CD-rom. Allott Study Guide revision: pp. 52-55
Powerpoints (S Taylor) for topics E.4 and E.5 Clegg reading (on CDRom): pp: 528-540*, Allott Study Guide pp: 136-138
Powerpoints (S Taylor) for topics E.1 and E.2 Clegg reading (on CDRom): pp 504-517*, Allott Study Guide pp 132-134
Powerpoints (S Taylor) for topics E.3 and E.6 Clegg reading (on CDRom): pp 518-528* & 541-551*, Allott pp 135, 139-140
* go the CD-rom for these pages - link to pdf of Clegg pages for Option E if needed
Powerpoints (S Taylor) for topics E.4 and E.5 Clegg reading (on CDRom): pp: 528-540*, Allott Study Guide pp: 136-138
Powerpoints (S Taylor) for topics E.1 and E.2 Clegg reading (on CDRom): pp 504-517*, Allott Study Guide pp 132-134
Powerpoints (S Taylor) for topics E.3 and E.6 Clegg reading (on CDRom): pp 518-528* & 541-551*, Allott pp 135, 139-140
* go the CD-rom for these pages - link to pdf of Clegg pages for Option E if needed
 6.5
6.5 Neuron Structure and Function/Homeostasis
Crash Course - Nervous System/Homeostasis
Terminology Auction - prepare flash cards for each of the following terms - include term and group #.
Follow along with the video and raise the appropriate card at the appropriate time - occasionally, there are 2 cards involved coincidentally and occasionally, the terms are appropriate, but are not actually spoken in the text of the narration!
CENTRAL VS PERIPHERAL
AFFERENT VS EFFERENT
SOMATIC VS AUTONOMIC
SYMPATHETIC VS PARASYMPATHETIC
DENDRITE
AXON
MYELIN
NODES
SYNAPSE
HOMEOSTASIS
RESTING POTENTIAL
DEPOLARIZATION
REPOLARIZATION
ACTION POTENTIAL
Na-K PUMP
Na CHANNELS
K CHANNELS
MEMBRANE POTENTIAL
THRESHOLD
NEUROTRANSMITTERS
Follow along with the video and raise the appropriate card at the appropriate time - occasionally, there are 2 cards involved coincidentally and occasionally, the terms are appropriate, but are not actually spoken in the text of the narration!
CENTRAL VS PERIPHERAL
AFFERENT VS EFFERENT
SOMATIC VS AUTONOMIC
SYMPATHETIC VS PARASYMPATHETIC
DENDRITE
AXON
MYELIN
NODES
SYNAPSE
HOMEOSTASIS
RESTING POTENTIAL
DEPOLARIZATION
REPOLARIZATION
ACTION POTENTIAL
Na-K PUMP
Na CHANNELS
K CHANNELS
MEMBRANE POTENTIAL
THRESHOLD
NEUROTRANSMITTERS
Neuron Structure http://www.microscopy-uk.org.uk/
A MORE DETAILED IMAGE OF A NEURON -
Lots of diagrams and electron micrographs of these cells available. This one tries to hybridize the two media. |
This is the man with the beautiful name...Louis-Antoine Ranvier, who discovered the nodes in 1878.
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Transmission through a neuron - Mechanism for Function
It's hard to show the mechanism of neural activity in a static picture, but this activity shows the interactions and allows you to pause and study the individual steps. Make sure you can explain the change in membrane potential with time.
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what does the myelin sheath actually do?
What is the difference in the two types of conduction? How does this connect to (1) demyelinating diseases, like MS? to (2) the requirement that infants drink high fat content milk?
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watch this animation through to the end and do the learning exercises.
This is a great place to make the connection between with the structure and function of the neuron and learning!
use the following materials to make your own model of a neuron pathway
dominoes
mouse traps
small balls of various materials - pingping, soft plastic, pompoms
Evaluate the accuracy of your model - where is it a good representation, where does it fall short?
mouse traps
small balls of various materials - pingping, soft plastic, pompoms
Evaluate the accuracy of your model - where is it a good representation, where does it fall short?
Biozone Workbook on Homeostasis - complete in your own copy
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 E.4/E.5
E.4 Synapses and neurotransmitters
(including action of drugs on the nervous system). But first start with some review of the neuron and synapse...
(including action of drugs on the nervous system). But first start with some review of the neuron and synapse...
Noe, how drugs interfere...IB assessment statements emphasize THC and cocaine...but look for the generalized mechanisms.
Illustration of excitatory vs. inhibitory drugs affect on synaptic transmission - particularly note the mechanism for cocaine (yellow)
great animation on how drugs interact with the nervous system...meet every mouse ot the Mouse Party. Excitatory or inhibitory? Mode of action??
THC and Cocaine mechanisms:
A presentation to resolve the apparent contradiction between THC being an inhibitory drug (true) and a drug that (indirectly) induces greater excitatory dopamine release (also true).
From the same resource, how cocaine connects with excitatory pathway
REDISCOVERING NEUROBIOLOGY
Where does this information come from - link to learn about the influence and results from patch clamping experiments.
In class reading/discussion of the excerpt from the Rediscovering Biology online textbook below.
In class reading/discussion of the excerpt from the Rediscovering Biology online textbook below.
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source: http://lalaleigha.wordpress.com/2009/08/10/the-pharmacology-of-marijuana/
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source: http://lalaleigha.wordpress.com/2009/08/10/the-pharmacology-of-marijuana/
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explanation of the suppression of inhibitory effects of THC...and the same effect is evidenced in many parts of the brain, explaining the diversity of effects
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An unusual feature of THC mechanism (above).
Simplified explanation of THC mechanism (below).
Quote from "Click4biology" clarifying the categorization of THC as an inhibitory psychoactive drug.
Above: Addiction across species lines...for a different perspective on E.4 topic. What characteristic features of addiction do you see (craving? lack of self-control? habituation? side effects/withdrawal behavior?...how about indications of causes - genetic, social, dopamine-controlled?
Genetic predisposition, Social factors and Dopamine secretion
Links to the resources used in class to address the influence of genes on addiction
Links to the resources used in class to address the influence of social factors and dopamine pathway to addiction.
More from crash course Hank...on cannabinoids. Click "Science" below.
E.5 The brain
Below: Link to a good review of brain structure and function.
excellent summary of brain structure and function for E.5...including interactive
a closer look at the "buried" structures of the brain stem...midbrain, pons, medulla oblongata - note how these are all bundles of neurons - lots of relay function
and think about the developmental patterning...
CNS/brain anatomy. (source: Clegg reading assignment, Chapter 17)
Example of functional magnetic resonance imaging...detection of the radio frequency energy emitted as magnetically polar hydrogen atoms, especially in water in the region of oxygenated hemoglobin, representing the respiration activity in different regions of the brain. (source: Clegg reading assignment, Chapter 17)
Still want more? - watch the most popular lecture at UC Berkeley...with Marian Diamond and her human brain in a hatbox.
Concussions, CTE and the brain
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2011 interview with Chris Nowinski
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Pupillary reflex response (E5)
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The Pupil Reflex...
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 E.1/E.2
E.1/E.2 Preview - Sensory Illusions/TOK and perspective! (video below)
E.1.1 Define...
E.1.2 Explain the role of...
E.1.3 Draw and label a reflex arc...
A few notes on the grey vs. the white...
White matter is so named because of the white appearance due to the fatty myelin protein surrounding the axons that predominate there. Thus, the white matter primarily consists of the axon portions of the neurons. Grey matter, in contrast, is where a preponderance of cell bodies, containing dense, darker-colored nuclei, is found.
As is seen in the table regarding E.1.2 above, which shows the neurons involved in a reflex arc, the motor neuron is completely consistent with this pattern, as the cell body is in the central grey matter in the spinal cord. However, the (much shorter) relay neuron is completely within the grey matter, and the longer sensory neuron is nearly completely in the peripheral nervous system, with the dendrite end stretching from the stimulus receptor to the dorsal root ganglion, where the sensory neuron cell body is located, and the sensory neuron axon continues to the synapse just inside boundary of the grey matter of the spinal cord.
Finally, to review, with respect to the two regions of the central nervous system (CNS), there is an interesting comparison here; in the cerebral cortex of the brain, the outer region is the grey matter, while in the spinal cord, the inner region is the white matter. Any ideas why?
White matter is so named because of the white appearance due to the fatty myelin protein surrounding the axons that predominate there. Thus, the white matter primarily consists of the axon portions of the neurons. Grey matter, in contrast, is where a preponderance of cell bodies, containing dense, darker-colored nuclei, is found.
As is seen in the table regarding E.1.2 above, which shows the neurons involved in a reflex arc, the motor neuron is completely consistent with this pattern, as the cell body is in the central grey matter in the spinal cord. However, the (much shorter) relay neuron is completely within the grey matter, and the longer sensory neuron is nearly completely in the peripheral nervous system, with the dendrite end stretching from the stimulus receptor to the dorsal root ganglion, where the sensory neuron cell body is located, and the sensory neuron axon continues to the synapse just inside boundary of the grey matter of the spinal cord.
Finally, to review, with respect to the two regions of the central nervous system (CNS), there is an interesting comparison here; in the cerebral cortex of the brain, the outer region is the grey matter, while in the spinal cord, the inner region is the white matter. Any ideas why?
E.1.4 Example(s) of Natural Selection Affect on Animal Responses - Behavioral Ecology - Research two "local" examples
IN CLASS RESEARCH ASSIGNMENT: Think about scarce resources, mating, rearing young, social behaviors such as kin relationships, cooperation vs. conflict, communication...You may choose any one of these. Gather information on (1) species, (2) habitat, (3) evolutionary pressure and (4) resulting change in behavior and (5) the connection between "3" and "4".
Here's an amazing FAP (fixed action pattern, a preferred term to "instinct"). Below is a even more amazing image with newborn humans.
Example from the literature:
Copy of the original scientific paper - possible assignment - active read, clarifying questions in class, summary, citing evidence from the tables and graphs
E2 - Survey of receptor types, Eyes and Ears - structure/function
See powerpoint slides and below for content presentation and review. Then, try a couple DBQ's, to review E1 and practice E2. Take the time to really read the given text and examine the data tables/graphs before you start to answer the questions. You will be less likely to get distracted with a misinterpretation or miss an important detail.
Types of Receptors
Eye - Structure & Function
Compare rods and cones
more on placement of rods and cones...
- (a) Bipolar cell forming synapses with more than one photoreceptor.
- (b) Bipolar cells connecting together rods and cones
- (c) Ganglion cell collecting input from a group of photoreceptors (receptive field)
- (d) Axon of the ganglion cell forming the optic nerve at (i)
- (e) Summation (convergence) of rod photoreceptors. Therefore when interpreted in the brain it will not be possible to tell which of the receptors was activated (absorbed light). This reduces the detail and gives low visual acuity (resolution) in this region of the field of vision. This is typical of the arrangement of rods and other neurons in areas outside of the fovea
- (f) Another form of summation.
- (g)The arrangement of cones in the fovea provides a high level of visual acuity (resolution). One cone synapses with one bipolar and one ganglion (h).
- (i) Notice how the axons of the ganglion come together to form the nerve fibers of the optic nerve.
Contralateral Processing
- Look closely, the left visual field information from ganglion in BOTH eyes goes to the right side of the brain.
- Equally for the right visual field object, the information ends up in the left side of the brain.
- The cross over point for optic nerves is the Optic Chiasm.
- The brain is able to integrate the 2 dimensional information of the retina back into a 3 dimensional perception of the ‘real world’.
Edge Enhancement
- Signals from rods and cones follow both vertical and lateral pathway
- Photoreceptors stimulate aligned bipolar cells but inhibit adjacent bipolar cells (lateral inhibition)
- This makes light spots lighter and dark spots darker, with the contrast greatest at the edges (edge enhancement)
- Overall, neighboring bipolar cells will "complement" one another's effects; but, at the edge of the stimulated area of cells, the "edge" bipolar cell has not been inhibited on one side, therefore the contribution of the edge cell is stronger/sharper.
The idea is that the retinal processing of information as previously described for edge enhancement sets up an illusion when looking at the Hermann grid. Presumably in the evolution of vision ‘eyes’ did not encounter 'Hermann grids' or if they did the illusion had no negative effect on the natural selection of ‘eyes’ . We might guess that the geometry of the Hermann will be so rarely encountered in nature that there has been no selection against ‘grey spot’ seeing.
When we look at one of the squares of the grid the spaces between (white lines) seem very bright. In this area the receptive fields of the fovea with their high visual acuity (resolution) are causing edge enhancement. However just out of the focus of our attention (non fovea) in the peripheral fields we are aware of the ‘grey squares’. The suggestion is that in these regions of peripheral vision:
We should remember that this is scientific theory and there are alternative explanations to the Hermann grid or at least some doubt that lateral inhibition theory is sufficient to account for the Hermann grid.
When we look at one of the squares of the grid the spaces between (white lines) seem very bright. In this area the receptive fields of the fovea with their high visual acuity (resolution) are causing edge enhancement. However just out of the focus of our attention (non fovea) in the peripheral fields we are aware of the ‘grey squares’. The suggestion is that in these regions of peripheral vision:
- Receptive fields are larger
- The fields have lower resolution
- Stimulation of the ganglion cell is a consequence of summation.
We should remember that this is scientific theory and there are alternative explanations to the Hermann grid or at least some doubt that lateral inhibition theory is sufficient to account for the Hermann grid.
Ear - Structure & Function
DBQ's
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 E.3/E.6
E3/E6 - Behavior, Innate, Learned, Further...
Perro ladrador, poco mordedor. - A barking dog doesn't bite much
(Spanish proverb)
Start with the intro lecture by Robert Sapolsky at Stanford, Human Behavior. Fabulous TOK connections, interdisciplinary ideas (think socio-political hierarchies found in both baboons and medical center employees) (You can skip the last ten minutes or so when he describes the nuts and bolts of how the course works - but you should be so lucky as to have this experience in person! He is hilarious!) And if you like this, work your way through the whole class.
If the link here is too slow, go directly to the youtube video.
As you view/after viewing the lecture, compose 5 questions/comments for discussion. Try to draw from/connect to the following animal behavior terms:
innate vs. learned
kinesis
conditioning
reasoning (insight behavior)
role of inheritance
social organization
community level natural selection
altruistic behavior - kin directed, reciprocal
foraging behavior
mate selection
rhythmical behavior - circadian, annual
innate vs. learned
kinesis
conditioning
reasoning (insight behavior)
role of inheritance
social organization
community level natural selection
altruistic behavior - kin directed, reciprocal
foraging behavior
mate selection
rhythmical behavior - circadian, annual
Innate vs. Learned? (E.3.1) Facial Expressions - what do we learn (or are we born with it) from Olympic Faces? What is so useful about learning anyhow? (E.3.4)
Types of Learning - Non-associative vs. Associative (Conditioning - E.3.5)
- cute babies, not-so cute rats (?) what are the crows and chimps doing?
- cute babies, not-so cute rats (?) what are the crows and chimps doing?
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Extensions of Associative - Operant Conditioning and Imprinting
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Birdsong - a combination of all of the above - Inherited, Innate, Imprinting
Birdsong - a combination of all of the above - Inherited, Innate, Imprinting - resulting in a non-visual way to demonstrate reproductive fitness, along the lines of more is better, listen to the lyre bird:
Birdsong Data Analysis (E.3.6) In-class assignment-Acoustic Spectroscopy
First go to the site, http://www.virtual-bird.com/birdsounds.htm and download songs from closely related (same genera) and less closely related (different genera) species. Import the audio files into Audacity (or Amadeus) and analyze the sounds via their sounds and their plot spectra (highlight one track, then, "plot, " then "analyze spectrum." Use screen capture to create a composite of spectrograph tracings. Label using the scientific nomenclature given.
First go to the site, http://www.virtual-bird.com/birdsounds.htm and download songs from closely related (same genera) and less closely related (different genera) species. Import the audio files into Audacity (or Amadeus) and analyze the sounds via their sounds and their plot spectra (highlight one track, then, "plot, " then "analyze spectrum." Use screen capture to create a composite of spectrograph tracings. Label using the scientific nomenclature given.
- What patterns of similarities or differences can you find?
- How much of the song appears to be genetically determined?
iBiology Slideshow subset - dry lab analysis on invertebrate behavior, required by assessment statement E.3.2-E.3.3.