Tuesday, January 31, 2012

Daily Newsletter January 28, 2012

 
 Daily Newsletter                                        January 31, 2012


Today's Topic: The Nucleus


It can be said that the nucleus defines the eukaryotic cell (question: why?).  The nucleus is a central structure present in eukaryotic cells, and is the site where we find the cell's DNA.  It is a highly regulated structure, and one function is to ensure the protection and stability of the cell's genetic information.


This is a double membrane bound structure, meaning there are two lipid bilayers that make up the nuclear envelope.The outer layer of the nuclear envelope gives rise to the endomembranous system, which includes the Endoplasmic Reticulum and the Golgi Apparatus.







To gain access to the inside of the nucleus, you must first move through nuclear pores (which are highly regulated).  Click on the link for more information on the nuclear pore complex.


Here is a video of the nuclear pore complex in action.  It does a good job with the visual, but there is one thing you need to realize with all gated portals in the cell: to get through, you must have the correct molecular key!


 The endomembranous system, which includes the Endoplasmic Reticulum and Golgi Apparatus is a continuation of the outer membrane of the Nuclear Envelope.  While the nucleus deals with DNA, and the transcription of DNA into RNA, the endoplasmic reticulum will deal with translation of RNA into Proteins and the production of lipids.  The Golgi Apparatus will deal with the process, storage and packaging of proteins and other products.  Why is it important that we have different compartments for the processing, storage and packaging of proteins?  


Here is a good visual of the Golgi Apparatus.







Daily Challenge:  Today, you can choose to write about of two topics (if you feel ambitious, you can write about both).  1)  Describe the nucleus, and in your own words, the action of the nuclear pores; 2) Describe the endomembranous system, and the production and processing of proteins.

Monday, January 30, 2012

Daily Newsletter January 30, 2012

 
 Daily Newsletter                                        January 30, 2012


Today's Topic: Prokaryote vs. Eukaryote


Today, students are to reflect upon two primary cell types:  Prokaryote and Eukaryote.  Consider that there are two domains of prokaryotes and only one for eukaryotic cell types.  The eukaryotic cell type is then divided into four kingdoms.


Read and do some research for the challenge today.  Here are two websites to get you started:


Daily Challenge:
In your blog, perform a comparison/contrast of the prokaryotic and eukaryotic cell type.  What can you say about their size?  Their structure?  Are there limitations, advantages?  Remember, both cell types are successful. 

Weekly Update 4 - Cell Structure

Weekly Update:  Week 4


TOPIC:  Cell Structure

The focus of this week will be on the animal cell, but note that a review of the prokaryotic cell and plant cell are part of your learning objectives.


Suggested Reading:
  • Chapter 6 - Cell Membranes from  Life: The Science of Biology by Sadava, Hillis, Heller, and Berenbaum.


Suggested Videos

Kinesin Waling  http://www.youtube.com/watch?v=YAva4g3Pk6k&feature=related

Mitochondria  http://www.youtube.com/watch?v=TgJt4KgKQJI&feature=related

Golgi Apparatus  http://www.youtube.com/watch?v=rvfvRgk0MfA


Learning Objectives
  • Be able to discuss and describe the Cell Theory.
  • Be able to describe the differences between prokaryotic and eukaryotic cells.
  • Be able to describe the basic structures of prokaryotic (bacterial) cells.
  • Be able to discuss how we study organelles and other cellular structures.
  • Be able to discuss the nucleus, including nuclear envelop, nuclear pores, and the nucleolus.
  • Be able to discuss the endoplasmic reticulum.
  • Be able to discuss the Golgi apparatus.
  • Be able to discuss the Lysosome and Peroxisome.
  • Be able to discuss the Mitochondira in detail.
  • Be able to discuss the Chloroplast.
  • Be able to discuss the cytoskeleton, including the three main structural elements:
    • Microfilaments
    • Microtubules
    • Intermediate filaments
  • Be able to discuss motor proteins and movement.
  • Be able to discuss cell walls and extracellular matrix.
  • Be able to discuss theories on the development of eukaryotic cells.

Administrative Notes: Please make sure that you send emails to ramaxwell@gsu.edu as discussed in the syllabus. Do not send emails to me through the social network or uLearn. I may not receive these emails, and will not have your return address. So make sure you use rmaxwell@gsu.edu.

Friday, January 27, 2012

Daily Newsletter January 27, 2012

 
 Daily Newsletter                                        January 26, 2012


Today's Topic: Evolution Friday

Daily Challenge:
You saw earlier how phospholipids can form membranes, but two questions arise:  how did we start getting proteins in the membrane, and how do we get the internal membranes found in eukaryotes?  Your task this Evolution Friday is to reflect on what you have learned, do a little research, and the answer these two questions.

Thursday, January 26, 2012

Daily Newsletter January 26, 2012

 
 Daily Newsletter                                        January 26, 2012


Today's Topic: Active Transport


In active transport, cells are moving substances across the membrane, but against the chemical concentration.  Chemicals are move from areas of low concentration to areas of higher concentration.  To move against a concentration gradient requires energy to overcome the inherent Brownian motion of the molecule.  This always requires protein (enzyme) pumps.  The word pump implies an active process that moves against a natural gradient or flow.


By far, the most commonly discussed pumps will be the ion pumps.  There are two that you should become familiar with, as well as the resulting gradients.
  • Sodium-Potassium ATPase (also known as the Na+/K+ pump).
    • This helps to establish and maintain the Sodium and Potassium gradients of a cell.
    • Sodium should be at high concentrations outside of the cell (extracellular)
    • Potassium should be a high concentrations inside of the cell (intracellular)
    • This combined gradient helps to establish the Resting Membrane Potential  of many cells (an electrical charge across the membrane).
  • Proton Pumps
    • These pump systems help to establish and maintain a proton (hydrogen ion) gradient.
    • In Eukaryotes, this will be found along the inner mitochondrial membrane.
    • In Prokaryotes, this will be found along the cell membrane.
    • This is a critical electrochemical gradient for cellular energy.
With both of these pump systems, we are creating electrochemical gradients, and both represent potential energy.


Commit the following phrase to memory:
When an ion moves down it's electrochemical gradient, across a membrane, work (kinetic energy) is done.

We will come back to this phrase throughout the semester.





Daily Challenge:  Na+/K+ pump
Using diagrams and text, describe the operation of the Na+/K+ pump.

Wednesday, January 25, 2012

Daily Newsletter January 25, 2012

 
 Daily Newsletter                                        January 24, 2012


Today's Topic: Passive Transport


The cell membrane is selectively permeable, so some things can make it through the phospholipid bilayer.  For other chemicals, we need to provide a protein to serve as a pore, channel or transporter.  In general, there are two ways that a chemical can be moved across the membrane:  Down the chemical's concentration gradient, or Against the chemical's concentration gradient.  When a chemical moves down it's concentration gradient, we do not need to add energy to the process.  The concentration gradient basically powers it's self.


There are three basic forms of passive transport through the membrane:
  1. Diffusion - Using the inherent Brownian motion of molecules, chemicals move from points of high concentration to points of low concentration.
  2. Osmosis - The movement of water across a selectively permeable membrane. 
    • Water goes to where the party is, meaning it will move to a compartment that has a higher solute concentration.
    • Since we are talking about two fluid compartments on either side of a membrane, we are ultimately talking about relative solute concentrations.
    • In biology we always use the inside of the cell as our reference, so:
      • An isotonic fluid has the same solute concentration as the inside of the cell.
      • A hypertonic solution has a solute concentration that is higher than the solute concentration inside the cell.
      • A hypotonic solution has a solute concentration that is lower than the solute concentration inside the cell.
    • Remember that we are looking at solute concentrations, not the concentration of a single chemical.
      • Diffusion gradients are specific for each chemical.
      • Osmosis is determined by total solute concentration.
  3. Facilitated Diffusion - Ultimately, this is diffusion, but the cell has had to provide a passage for the chemical.  So, this only applies to chemicals that can not normally pass through the phospholipid bilayer.
    • The cell provides a protein channel or pore for the chemical to pass through.
    • Each channel or pore is specific to a single chemical or set of chemicals.
    • Since this is an protein (enzyme) mediated action, the ability to transport follows standard enzyme kinetics.
    • The core idea about facilitated diffusion following enzyme kinetics is that diffusion becomes limited by the number of channels or pore available.  Standard diffusion is not limited.
In each case, the cell does not need to expend energy to move the chemical across the membrane.  The motive force is built in to the chemical gradients.  Remember, the cell membrane is going to provide an internal vs. an external space (compartment).  Each side of the membrane will have a unique chemical profile.  As such, there will be concentration gradients across the membrane.



Daily Challenge:  Passive transport
In your own words, describe passive transport.  Concentrate on osmosis and facilitated diffusion by providing an example that illustrates each action.  Make sure you use an example that uses a cell (not beakers, flasks, etc...).

Tuesday, January 24, 2012

Daily Newsletter Jaunary 24, 2012

 
 Daily Newsletter                                        January 24, 2012


Today's Topic: Cell Recognition and Cell Adhesion


Cells must have the ability to sense their environment, and part of this is to be able to sense and recognize other cells.  In a multicellular organism, individual cells must be able to recognize other cells that are part of the same organism, and must be able to anchor to them.  Mutlicellularity requires cells to be anchored to each other.


For example:  Would you be able to move if your muscles were not somehow anchored to the bone?  Would your skin be a defensive structure if it separated when you pulled it?  Would your cardiovascular system be able to transport blood if there the pressure would rip open the vessels?


In terms of recognition, we also have to have the ability to determine if something is part of the "SELF" or foreign.   We will find that the ability for cells to recognize each other will be an important concept in many areas of biology, most notably, immunology.


NOTE:  For your notebook, you should keep a brief description of the three main cell junctions found in animals:  tight junction, desmosome and gap junctions.  They will come back up later.



Word of the Day:  Glycoprotein.
This is a new feature for the newsletter.  The word given is something that you should make sure you have in  your notes.  You do not need to add this to your blog, just make sure you know the term.  In many cases, such as this, you may also want to look up some examples.


Daily Challenge:  Recognition
As a focus on cellular recognition, you are to blog about the Major Histocompatability Complex.  You can look up the word in the textbook index, or do a web search.  As always, Wikipedia is a fine starting point (their article on MHC contains useful background information).  The blog is to focus on the importance of cellular recognition, using MHC as the example.  This example is very important, as it plays a major role in the immune system.

Monday, January 23, 2012

Daily Newsletter January 23, 2012

 
 Daily Newsletter                                        January 19, 2012


Today's Topic: The nature of the cell


The cell theory describes the importance of the cells to biologists.  How important is it?  Well the first part of the cell theory answers that:  All known living things are made up of one or more cells.  But what ultimately is a cell?  What takes place in one?  Why are they so important?


It will take a few discussions to get to all these questions, but there is a starting point.  As a basic description, the cell is a self-managing, self-contained chemical factory.  Cells take in materials, use these for energy and building blocks, and then produce materials to keep the cell healthy, harvest nutrients, eliminates waste, and produces products.  The cell has many components to accomplish these tasks:  DNA for management, chemical signals to send messages, enzymes for chemical activity, etc....


Let's look at the analogy of a chemical factory:  Inside a factory, there are going to be different processing places for different chemicals.  There are going to be pathways of pipes going between vats and other structures.  Taking a further look back, there is a building, with trucks coming and going.  


Inside of the cell, chemical reactions will be taking place.  Outside the cell, chemical reactions are taking place.  Are they the same chemical reactions?  One of the foundations of cells is that the inside of a cell is a spatial area with a defined concentration of a variety of chemicals that is distinct and different from the chemical concentrations found outside of the cell.  


So, there is an inside and outside of a cell, and they are different.


You will hear me say again and again that the cell membrane is the defining structure of a cell.  Why?  Because it establishes the boundary.  When you have a cell membrane, you can have an inside as opposed to an outside of a cell.  If you loose that membrane, you start moving to a full equilibrium between the inside and outside of the cell.  If you loose the membrane, or it gets holes, the cell dies.  The cell dies when you cease to have an inside vs. an outside.


The fastest way to kill a cell is to poke holes in it.



Daily Challenge:  The cell membrane
Today, I want you to discuss the basic structure and functions of the cell membrane, focusing on this idea that it provides the essential, and foundational, separation between the inside and outside. 

Weekly Update 3 - Cell Membranes

Weekly Update:  Week 3


TOPIC:  The Cell Membrane

This week we will be looking at the cell membrane as a fundamental structure of biology.


Suggested Readings:
  • Chapter 6 - Cell Membranes from  Life: The Science of Biology by Sadava, Hillis, Heller, and Berenbaum.
  •  Cell Theory - This wikipedia article give a good description of the history of the cell theory as well as a point-by-point description of the modern cell theory.  The latter point-by-point is a great blurb to keep in your note.

Learning Objectives
  • Be able to discuss the cell theory and its applications and importance in biology.
    • Remember:  As a theory, this is a model used to help inform our investigations in biology.
  • Be able to discuss the structure and function of a biological membrane.
    • Be able to answer this question:  Why is the cell membrane the defining structure of the cell?
    • Be able to describe the role phospholipids, sterols and proteins play in the cell membrane.
    • Be able to describe the Fluid Mosaic Model of the cell membrane.
    • Be able to describe why the membrane is dynamic, and why it is important for the membrane to remain dynamic.
  • Be able to discuss cellular adhesion, and the different forms  of cellular adhesion.
  • Be able to discuss cell recognition.
  • Be able to describe the passive processes of diffusion and osmosis.
  • Be able to describe facilitated diffusion.
  • Be able to describe Active Transport.
    • Be able to describe the sodium/potassium ATPase transport system.
    • Be able to describe the proton motive force.
  • Be able to describe endocytosis, including phagocytosis, and exocytosis.

    Friday, January 20, 2012

    Daily Newsletter January 19, 2012

     
     Daily Newsletter                                        January 19, 2012


    Today's Topic: Evolution Friday


    One field in the study of evolution is proposing and testing hypotheses regarding the origin of life.  These studies have the potential to be high profile science, even earning the cover of prestigious journals such as Science.  While most evolutionary studies are concerned with existent organisms, research in life origins helps biologists put biomolecules and genetics into perspective.  This research is also foundational for not so science fiction topics like terraforming.



    Today's Challenge:
    Explain the concepts of macromolecule evolution and the evolution of cells.  Feel free to discuss the concept of prebiotic molecules.  Throughout your discussion, I want you to focus on how this information informs our current understanding of existent cells and organisms.  How does membrane evolution influence our thoughts today?  Why is it important that membranes formed?  How is RNA as a catalyst important?

    Thursday, January 19, 2012

    Daily Newsletter January 19, 2010

     
     Daily Newsletter                                        January 18, 2012


    Today's Topic: Nucleic Acids


    Today we turn our attention to the basic structure of nucleic acids.  We are talking about Ribonucleic Acids and Deoxyribonucleic Acids.  The two critical concepts to master today are the general structure of nucleotides (monomers of nucleic acids) and the concept of base complementarity.  


    Nucleotide Structure:  
    The following image from wikipedia's image gallery shows the basic structure of the nucleotide and the five nitrogenous bases.
    The central component of all nucleotides will be a pentose sugar (5-carbon sugar).  We will either see ribose or 2'deoxyribose as the sugar.  Off of the 5' carbon of the sugar, you will find a phosphate group attached, while on the 1' carbon, you will find a nitrogenous base.  Three are five nitrogenous bases, divided into two categories:  Purines and Pyrimidines.  Notice that the purines are a composite of two ring structures, while the pyrimidines are a single ring structure.  When you take organic chemistry and biochemistry, the importance and complexity of these ring structures will be further discussed.  At present, just become aware of their respective shapes and sizes (and inclusion of nitrogen).


    As with amino acids, the nucleotide contains a functional group: the nitrogenous base.  Just like the side chain in an amino acid, the nitrogenous base will play an important part in the function of this biomolecule.  The Sugar-Phosphate then becomes the backbone of the molecule (line the Amino-Chiral Carbon-Carboxyl of an amino acid).  We will in later weeks that the sugar-phosphates of nucleotides will create the strands of DNA and RNA.  The nitrogenous bases then playing an information role.


    Base Complementarity:  
    The nucleic acids are referred to as informational biomolecules (biopolymers).  This is because the sequence of nucleotides carries information on how to build RNA and Proteins.  One of the central foundations of genetics (i.e., how it all works), is base complementarity.  Here we are looking at the interactions between purines and pyrimidines:

    A links with T through 2 hydrogen bonds.

    G links with C through 3 hydrogen bonds. 


    A to T     G to C


    U has the binding properties of T, but is only found in RNA.
    T is never found in RNA, only DNA.



    Daily Challenge:
    Review the history of the discovery of DNA.  When did people first suspect that DNA was the molecule of inheritance?  Who figured out the structure of DNA?  Who figured out how DNA was replicated?

    Wednesday, January 18, 2012

    Daily Newsletter January 18, 2012

     
     Daily Newsletter                                        January 18, 2012


    Today's Topic: Carbohydrates and Lipids

    While carbohydrates are mainly used as chemical energy storage, carbohydrates are also used as modifiers of proteins. The goal today is to get a good understanding of the structure of carbohydrates, and a little about their naming.

    A topic that will come up throughout the semester is how carbons are numbered in carbohydrates.  This is important as we will find carbohydrates being components of monomers and when we move through the carbohydrate catabolism.  The following image from Rensselaer Polytechnic Institute shows the linear form of glucose, and the two possible cyclic (pyranose ring) isomers.
     The formation is based on aldehyde chemistry, so we will leave some of this discussion to organic chemistry and biochemistry.  For our purpose this semester, what is important is that we number carbons from the aldehyde.  Notice in the above diagram that carbon 1 is to the left of the oxygen, we go around to carbon 5, and then carbon 6 is outside of the ring.  If you see the expression 3', it is referring to the third carbon.  5' the fifth carbon.  6' the sixth carbon, and so forth. 

    Notice also, that when the ring was formed, there were differences in the groups coming off of carbon 1.  These differences are important, and can influence how the sugar is metabolized. 

    One critical difference here comes when linking two monosaccharides together to form disaccharides and polysaccharides.  For instance (again from rpi.edu), here is maltose:
     This is an α 1-4 glycosidic linkage.  We have an α Maltose (look at carbon 1) bound from carbon 1 to carbon 4.  Since the maltose on the left hand side is α at the 1 carbon, we form an α linkage.  In comparison, look at cellobiose:
    Cellobiose has a β 1-4 glycosidic linkage.  The designation of β comes from the sugar unit that donates carbon 1 to the bond.

    So, what is the big deal?  Maltose is digestible by humans, cellobiose is not.  Just this slight isomeric difference changes the metabolism.

    Today's Notes:  In our face-to-face time, we will talk about triglycerides and phospholipids.  Please take the time to read about these two lipids, and come prepared to discuss.

    Today's Challenge:
    Beyond dietary sugar, what can sugars do in biological organisms?  HINT:  Look at things as diverse as cellular receptors and markers (blood type), all the way to mucous.

    Tuesday, January 17, 2012

    Daily Newsletter January 17, 2012

    Daily Newsletter                                        January 17, 2012


    Today's Topic: Proteins


    Proteins will be a reoccurring topic throughout the semester.  They are one of the informational biopolymers.  This means that they are composed of monomers (amino acids) that are linked together in specific sequences that are critical to their overall structure and function.    [NOTE:  It is important to understand the terms monomer and polymer, so make sure you have a good definition of these terms in your notebooks.]  To understand proteins, we must first understand their monomeric unit, the Amino Acid.




    Remember that all monomers will be chemically similar.  In the case of the amino acid, the base molecule of Amino-Chiral Carbon-Carboxyl is the same.  The difference in the amino acids comes with the side chain.  These functional groups give each amino acid its unique identity and function.  The twenty amino acids that are used in natural proteins can be found in the following link:  Amino Acid Diagram.  Notice that there are four general classes of amino acids with different chemical properties based upon the functional group.


    The base molecule is needed to link amino acids together into a polymer.  A condensation (dehydration synthesis) reaction is used to form peptide bonds, the specific bond type that links amino acids together.  [NOTE: biopolymers (save for lipids which are not polymers) have specific names for the bonds between monomers.]  In the formation of a peptide linkage (bond), you will have a carboxyl and amino group linking together, with water being a product.




    This linking of amino acids through peptide bonds will create the primary structure of a protein.  All of the remaining levels of protein structure will result from interactions between functional groups on the amino acids.  Local interactions induces folding into the secondary structures, which will result in other amino acids coming into close contact.  This results in a tertiary structure.  Finally, you will get a quatrenary structure when multiple individual folded peptide chains come together.  Remember that Van der Waals forces (including hydrogen bonds), covalent bonds (disulfide bridges), and hydrophobic interactions will all induce folding.  Because of this, environmental factors (such as heat or pH) can influence the folding pattern and shape of a protein.




    Daily Challenge:  Protein Folding
    Today's challenge is tough, and will require you to do some extra reading and research.  Hemoglobin is critical to oxygen tranport in many animals.  It is an amazing protein that is influenced by body pH and temperature.  Minor alterations in hemoglobin can cause radical changes in its ability to carry oxygen.  Students are to look at two major changes in hemoglobin:  
    1. When you exercise, your muscles warm up and give off acidic metabolic waste.  How does higher temperatures and acidic conditions change the shape of hemoglobin, and theirfore its ability to hold oxygen?  Hint:  Look up an oxygen dissociation curve and its explaination.
    2. Sickle Cell Anemia is the result of a small mutation in the gene that codes for β-Hemoglobin.  Only one amino acid is different.  Explain how and why a single amino acid change can cause the problems seen in sickle cell anemia.  Hint:  Look up the pathophysiology of sickle cell anemia as a starting point.



    Monday, January 16, 2012

    Weekly Update January 16, 2012

    Weekly Update:  Week 2

    TOPIC:  Chemistry

    This week, students are asked to review general chemistry and start their exposure to biochemistry.  During this week, we will be focus our studies primarily on biochemistry.

    Suggested Reading:

    Chapters 2, 3, 4 of  Life: The Science of Biology by Sadava, Hillis, Heller, and Berenbaum.
      • Chapter 2 is a review of general chemistry.
      • Chapter 3 focuses on Proteins, Carbohydrates and Lipids.
      • Chapter 4 focuses on Nucleic Acids.
    • The following two wikipedia articles are jumping off points for protein folding.  This is a critical topic, so use these as a way of delving deeper into this topic

    Learning Objectives
    • Review Previous Knowledge: Atomic Structure.
    • Review Previous Knowledge: Bond Types
    • Review Previous Knowledge: Chemical Reactions
    • Review Previous Knowledge: Properties of Water.
    • Demonstrate an understanding of biopolymers and macromolecules.
    • Be able to identify the monomer of each class of biopolyer, its functional groups, and potential isomers.
    • Be able to discuss how form and function are interrelated in biopolymers.
    • Be able to describe condensation and hydrolysis reactions as related to biopolymers.
    • Be able to describe the core structure of an amino acid and the formation of a peptide bond.
    • Be able to describe how a protein folds into a functional end product.
    • Be able to describe the reasons why proteins fold (chemical properties).
    • Be able to describe how the environment can affect protein folding (denaturation).
    • Be able to describe the funciton of chaperones.
    • Be able to discuss the function of proteins
    • Be able to discuss the different types of saccharides and chemical modification of saccharides.
    • Be able to discuss the numbering of carbon atoms in a sugar molecule.
    • Be able to discuss the formation of glycosidic linkages (bonds) and how isomers affect these bonds.
    • Be able to discuss the function of sugars.
    • Be able to discuss the triglyceride, saturated and unsaturated fatty acids, and phospholipids.
    • Be able to discuss the chemical structure of mucleic acids.
    • Be able to discuss the differences between RNA and DNA.
    • Be able to discuss the theories of how RNA, DNA and life originated.

    Schedule

    We have class Thursday January 19th.  By that point, we will have had newsletters covering Proteins and Carbohydrates (possibly a little about lipids).  On Thursday we will start with a review of these topics.  In a review, you will be asked to discuss areas that you have found difficult.  The last part of the class will deal with nucleic acids.

    Quiz 1 ends on January 20th.
    Quiz 2 ends on Jaunary 22nd.
    Quiz 3 ends on January 24th.

    Friday, January 13, 2012

    Daily News Letter January 13, 2012

    Daily Newsletter                                        January 13, 2012

    Today's Topic: Evolution Friday

    Welcome to evolution Friday.  Every Friday we will discuss evolution in context of the week's topic.  This week is an introduction to the topic of evolution.

    First, you must remember that as scientists we build models to help us understand how the world works, and to provide the ability to predict and control natural phenomena.  Evolutionary theory is no different.  The model we create regarding evolution allows us to look at the diversity and interrelation of living organisms, understand strong connections between organisms, and even understand what happens when population sizes get low (endangered species).  Our modern model of evolution can stated at a simple level as the changes in phenotypic frequencies within a population through time.  Let's analyze that statement:
    1. Phenotype:  This is the physical, expressed form of an organism.
    2. Population:  A group of individuals of the same species inhabiting the same time and space (habitat).
    3. Unless there is an identical twin, each organism in a population is phenotypically unique (diversity).
    4. Even with this diversity, there is a range of expressed phenotypes; or a phenotypic ratio.
    5. Evolution looks at this phenotypic ratio over time to see if there are changes.
    6. Another way to look at this right now is to say that we are looking at the PREVALENCE of a given phenotype (characteristic) over time.
    A good example of this comes from the historic changes in the phenotype of the pepper moth.  A fun online tutorial about the pepper moth can be found at http://www.techapps.net/interactives/mothproject.htm.  In reading the article and going through the tutorial, keep in mind that what you are looking at are population level shifts in the frequency in which you see a given form.

    The idea that natural selection can affect phenotypic frequencies is a central model used in biology.  It informs our hypotheses and conclusion.

    Read the following article:




    Daily Challenge: Evolution


    This challenge has two components. First I would like you to discuss the modern concept of evolution in your own words by answering the question: What is Evolution? Second, I would like you to read the above article and discuss the following question: How does evolutionary theory inform the conclusion to this article? Another way to put this, how does evolutionary theory inform the author's conclusion about the stability of grasslands.

    Welcome Letter


    This message was sent earlier in the week.  I am resending it for anyone who recently added the class.
    I would like everyone to log into the social network site by Monday.

    Welcome back from break, and to Spring 2012 here at GSU.
    I’m writing to help get you prepped for BIOL 2107, Principles of Biology I. This semester, I am teaching this as a hybrid on-line face-to-face course. After the first week, we will be meeting once a week throughout the semester, and the rest of the time we will be working online. I have great expectations for you, and I hope that you will use the opportunity of this semester to really nail down some fundamentals.
    To get you ready for the course, I need you to do the following:
    1. Go to the syllabus website https://sites.google.com/site/hybridbiol2107/
      • Bookmark this page for quick reference.
    2. Watch the What is a MOOC? Video
    3. Join our biology social network Biology MOOC.
      • To protect your privacy while you are a student, you are encouraged to come up with a non-offensive pseudonym for your User ID.
      • In uLearn, you will be given an opportunity to log your User ID with me (there is an assignment on the main page for this).
      • Once you have logged on, I want you to start your blog.
      • In your blog, tell the community what you hope to achieve (not grades) this semester in taking BIOL 2107 (btw…you will get points for doing this).
    4. If you are on Facebook, then join our facebook group http://www.facebook.com/pages/GSU-Biology-MOOC/268219026574421
    5. My twitter ID is bioramaxwell.
      • If a problem occurs during the semester, or if a class is canceled, I will send out a tweet and then announcements on as many systems as I can.
      • There are also opportunities for students who use twitter.
    6. Install Zotero on your computer.
    7. Log onto uLearn, and then go to the course page.
      • Take a quick tour to get familiar with what is on uLearn.
      • Over the next few days, materials will appear.
    8. Log onto OrgSync and start building an ePortfolio.
      • Instructions on how to access OrgSync are in the course uLearn page.
      • Information about ePortfolios can be found in the syllabus.
    As a reminder, labs begin during the first week of the semester. Make sure that you attend your scheduled lab!
    Looking forward to seeing everyone on Tuesday!

    Thursday, January 12, 2012

    Daily Newsletter January 12, 2012

    Daily Newsletter                                        January 12, 2012

    Today's Topic:  Science or Pseudoscience


    Remember, to be scientific, a hypothesis must be both testable and falsifiable.  Pseudoscience is any claim held to be “Scientific,” but which fails to the standards of scientific research.  Most notably, pseudoscience is known for having hypothesizes that are untestable or non-falsifiable.

    It must be remembered that Pseudoscience is a claim to knowledge supposedly based in scientific methodology.  In fact, it fails to be scientific.  It just makes the claim.  Religion/Revelation/Spirituality does not make an authority claim based on science.  Therefore these topics are not classified as pseudoscience. 

    Most spiritual pathways are based upon personal revelation, or private knowledge.  Acceptance of private knowledge is the foundation of belief (not science).  Public knowledge on the other had must be based upon evidence.  Consider this phrase:  “Why should I accept what you are saying?”  The phrase shows a healthy amount of skepticism, and normally what we are looking for when we ask this question is what proof you have to support your claim.  Understand:  Private Knowledge (anecdotes) are still knowledge, and they can be helpful in your life; they are just not scientific.  Take for example when a parent, grandparent or older sibling says:  “Don’t do that, you’ll regret it.”  Are they necessarily speaking from observed, empirical or measurable data?  Are they speaking from public knowledge?  or are they speaking from personal experience (private knowledge)? 

    Pseudoscience is a term that is thrown around a lot, and sometimes when it is not warranted (usually to discredit a controversial theory).  Here are some examples of protosciences (new sciences) that were first called pseudoscience:
    • Big Bang Theory
    • Continental Drift
    • Electromagnetic Field Theory
    • Germ Theory of Disease


    Daily Challenge: Looking at science and pseudoscience

    Consider the following "scientific" activities.  I use the word scientific in quotes to denote that most consider these activities pseudoscience.  What is your take on these?  Can legitimate hypotheses be formulated?
    • Parapsychology
    • Psychic Phenomena
    • Energy Medicine
    • Acupuncture
    • Ghost Hunting

    NOTE:  When to be skeptical (things to watch out for)

              Heresy does not equal correctness
              They laughed at Galileo!”
              Anecdotes do not equal scientific evidence
          “After my neighbor’s daughter started drinking wheat grass, she never had another asthma attack.”
           This is a revelation at best, and so is not scientific.
          Could this lead though to a testable hypothesis?
              Failures are rationalized
        “If faith-healing doesn’t work, it is because your faith isn’t strong enough.”
          This statement makes the hypothesis non-falsifiable.
          Could faith-healing be tested in an objective, scientific environment?
              Unexplained is not inexplicable
          “People who walk on hot coals must have paranormal powers.”
              Arguments are carried to absurd conclusions
           “100% of divorced people were once married, therefore marriage causes divorce.”
              Ad hominem attacks
              A personal attack, literally, an attack against the person.
              “A woman who demands equal rights just can’t get a man.”
              Circular Reasoning
         “What is gravity?”
         “The tendency for objects to be attracted to each other.”
         Why are objects attracted to each other?”
         “Because of gravity.”
              Assuming that correlation indicates cause
         “A high number of students who do well on the SAT have had braces, therefore, intelligence is caused by crooked teeth.”