Movement Across the cell membrane

So in class we learned about diffusion, and the channels within the cell membrane. The definition of Diffusion is the movement of high to low concentration.

CELL MEMBRANE
The cell membrane is a buffer zone between the internal cell, and the outside of the cell. Cells need to get material in, and wastes out. The cell membrane allows for things such as food, carbohydrates, sugars, proteins, amino acids, lipids, salts, oxygen, and water. The cells need to get wastes such as ammonia, salts, carbon dioxide, water, extra sugar, and other products out of the cell. They are stern. Stern but fair. They must be tough.

As you can see the membrane surrounds the cell, and makes sure only necessary materials get in and out.
DIFFUSION THROUGH A PHOSPHOLIPID BILAYER
Since the middle of the phospholipid bilayer is non polar, only other non-polar molecules can get through, such as Fats and other lipids. Water, other polar molecules, ions, and large molecules cant get though. It's like a hip Hollywood party. Only the coolest celebrities get access, Fats, and other lipids. Polar molecules, ions, and large molecules aren't "cool" enough to get into this party.
CHANNELS THROUGH CELL MEMBRANE
Protein Channels make a membrane semi-permeable. Certain channels allow certain membranes across into the cell.

FACILITATED DIFFUSION
This is just simple diffusion through a membrane channel. When a channel and a molecule are right for each other, the channel moves a specific molecule across the channel into the cell. This doesn't require any energy.
ACTIVE TRANSPORT
Sometimes high to low concentration just isn't the cool thing to do. Therefore molecules must succumb to peer pressure and go against the concentration gradient. The protein pump, changes its shape to transport the molecules from one side to another. What does this cost you may ask? ATP. Energy. you know.LARGE MOLECULES
Large molecules need loving to. You know what I'm saying. They can move in through vesicles, and vacuoles. There is endocytosis, and exocytosis.

Endocytosis has two parts.
-Phagocytosis is "cellular eating". I mean cells get hungry too. It is a process where cells absorb material ( molecules such as proteins) from the outside by engulfing it with the cell membrane. -pinocytosis is "cellular drinking". is a form of endocytosis in which small particles are brought into the cell suspended within small vesicles which subsequently fuse with lysosomes to hydrolyze, or to break down, the particles.
Exocytosis is the process in which a cell directs secretory vesicles to the cell membrane.
that should be sufficient

REGULATING THE INTERNAL ENVIORNMENT

Regulating the Internal Environment


Conforemers vs. Regulators
There are two evolutionary paths for organisms, they can either regulate their internal enviornment or conform to their external environment. When organisms regulate thier internal enviornment they are able to maintain a relatively constant internal condition, when they conform they allow their internal conditions to fluctuate along with
any external changes.


Water Balance and Nitrogenous Waster Removal
As there was a change from unicellular to mutlicellular organisms the syestems within animal had to evolve in order to support all multicellular life.One can see this through the respitory system, digestive system and circulatroy system all working together. Through entry ways foods and other materials are entered into the body but at the same time both extra cellular waste and intrecellular waste are being removed. Another example is systems built inside larger cells. Becasue the cells have divided and therefor created a larger surface area the cells inside are not exposed to water and there for are not able to diffuse items into them, but becasue
these cells have systems that creates entry ways into them they are able to gain materials no matter what their location maybe.


Solving Exchange Problems
In order to over come the limitations of diffusion certain systems much have evolved.Exchange systemes are of use in distributing nutrients by the circulatory system and removing of wastes through the excrectory system.


Osmoregulation
We were also introduced to the beginnings of osmoregulation or the balancing of water.Osomoregulation is determined by where you live and the amount of water in your surronding areas.Organims found in fresh water will regulate their water systems differently then let say those found on land due to the amount and the type of water that is availible to them.





pardon the lack of pictures, but the system doesn't seem to be working in my favor today
and our next report will be delivered by Alex.
Enjoy! =)

Diffusion 101

For the past few days we have learning the basics of diffusion.

But what is diffusion?

Diffusion refers to the process by which molecules intermingle as a result of their kinetc energy of random motion.

We having been trying to figure out why cells can not get infinetly large. This is because the rate of diffusion will always remain the same; therefore if the cell gets too big the middle out the cell with die because it will not get nutrients fast enough or waste out fast enough. In order words the surface area to violume ratio will work against the cell.

In the cell races lab, six teams compete to make the cell with the most mass and the smallest diffusion time. Congrats to Muskan's group for winning in our class!

In our labs we also tested to see what elements would diffuse across the cell membrane. We set up an experiment with one beakers. In the beaker we placed water and a tester and in the diffusion tube we placed water starch and glucose.

In conclusion we found that the tester, water, and glucose diffused in and out of the cell; however starch did not because the molecule was to big.

Starch looks like this:

or like this:

Theme 8: SCIENCE, TECHNOLOGY & SOCIETY

Theme 8: SCIENCE, TECHNOLOGY & SOCIETY
Explanation: Scientific research often leads to technological advances that can have positive and/or negative impacts upon society as a whole.
Clarification: You would post here examples of how technological innovations have helped advance science whil ethose technolical accomplishments may have also had either beneficial or deleterious impacts on human society.

Theme 7: INTERDEPENDENCE IN NATURE

Theme 7: INTERDEPENDENCE IN NATURE
Explanation: Living organisms rarely exist alone in nature.
Clarification: You would post here examples of how organisms must interact together to live successfully.

Theme 6: REGULATION

Theme 6: REGULATION
Explanation: Everything from cells to organisms to ecosystems is in a state of dynamic balance that must be controlled by positive or negative feedback mechanisms.
Clarification: You would post here examples of how a dynamic equilibrium is maintained at different levels of life, from homesostatic control of cellular and body conditions to maintenance of population levels in ecosystems.

Theme 5: RELATIONSHIP OF STRUCTURE & FUNCTION

Theme 5: RELATIONSHIP OF STRUCTURE & FUNCTION
Explanation: The structural levels from molecules to organisms ensure successful functioning in all living organisms and living systems.
Clarification: You would post here examples of structure-function relationships in living organisms. How specific molecules, organelles, cells, tissues, organs, and body structures are structured to support the functions that they perform. (Don't forget plants!)

Theme 4: CONTINUITY & CHANGE

Theme 4: CONTINUITY & CHANGE
Explanation: All species tend to maintain themselves from generation to generation using the same genetic code. However, there are genetic mechanisms that lead to change over time, or evolution.
Clarification: You would post here examples of how organisms reproduce while maintaining the same genetic information from generation to generation AND also examples of how organisms reproduce while accumulating changes to their genetic information from generation to generation.

Theme 3: ENERGY TRANSFER

Theme 3: ENERGY TRANSFER
Description: Energy is the capacity to do work. All living organisms are active (living) because of their abilities to link energy reactions to the biochemical reactions that take place within their cells.
Clarification: You would post here examples of how organisms are able to capture energy and utilize it to do the work that supports life.

Theme 2: EVOLUTION

Theme 2: EVOLUTION
Description: Biological change of organisms that occurs over time. Which is driven by the process of natural selection. Evolution accounts for the diversity of life on Earth.
Clarification: You would post here examples of evolutionary change in populations of organisms that we have been able to observe or have evidence of.

Theme 1: SCIENCE AS A PROCESS

SCIENCE AS A PROCESS
Description: Science is a way of knowing. It can involve a discovery process using inductive reasoning, or it can be a process of hypothesis testing.
Clarification: You would post here examples of how the scientific process has been used to develop our knowledge about how the biological world works.

Our Grand Tour of the Cell

okay, so now that we're done with Biochemistry, we've moved on to learning about the cell and it's structure. So, let's get started.

The first thing we talked about today was the three types of cells. The three types of cells are prokaryotic, eukaryotic animal, and eukaryotic plant cells.

The main difference between prokaryotic cells and eukaryotic cells is that eukaryotic cells have organelles and are compartmentalized whil prokaryotic cells are not.

Why Organelles?

-Organelles are important because they are specialized structures that carry out specific functions. Also, they act as containers that separate different parts of the cell so they do not affect each other. If there was not this compartmentalization, then the environments of each organelle would mix with the others, and most of the organelles would be damaged and unable to perform their designated function. Lastly, organelles are important because the membranes serve as sites for chemical reactions to take place.

Jobs of Cells

-Cells have three basic jobs that they must do. First, they must build proteins. They need proteins because proteins control every function of the cell. Proteins are the things that actually create new cells from DNA. As fillmore said today, DNA gets the glory, but proteins do all the work. Second, cells need to make energy, or ATP. The cell needs this energy to do everyday processes and for growth. Third, the cell needs to build more cells for growth, repair, and reproduction.

Building Proteins

-There are many organelles involved in building proteins. The production of proteins starts at the nucleus, where DNA is changed into RNA for transport to the ribosomes in the endoplasmic reticulum. The ribosomes then use the RNA to make proteins, which are then transported from the ER to the golgi apparatus by a transport vesicle. The golgi apparatus pretty much acts like a little UPS truck. It basically figures out where the protein needs to go, and sends it there in another vesicle.

Making Energy

-Why do cells make energy? Cells make energy because they need power. Without it, the cell would not be able to perform many of its daily tasks. On a daily basis, cells need to take in and digest food, take in oxygen, make ATP, and remove waste.

Lysosomes

-Lysosomes are the "little stomach" of the cell. They digest macromolecules and old organelles in the cell to help keep it clean. Without them, the cell would keep accumulating waste with no way to get rid of it, and would eventually be filled with wastes and be unable to perform any life processes. This is why it becomes so fatal when lysosomes do not work properly. When your lysosomes do not function properly, you can develop a lysosomal storage disease. There are over 40 different kinds of this disease, the most common being tay-sachs disease and hunters disease. Most often, people with these diseases die young and do not live past the age of three. This is why the proper function of lysosomes is extremely important.

That's it for today, today's lesson will be continued tomorrow by Jess.

Nucleic Acids

Hey guys. I know today was the happiest day for everyone because today we finally finished biochemistry. We are finally over with chemistry!!!!!!!!!!!!!!!!!!!!!!!!

Today we finished off biochemistry with Nucleic acids. Nucleic acids are the information storage devices of our cells. Not only do nucleic acids store information but they also transmit hereditary information to the next generations. Nucleic acids are able to serve as templates to produce precise copies of themselves, so that the information that specifies what an organism is can be copied and passed down to its descendants. The information that is being passed on between generations of organisms is the ability to produce the correct proteins. There are two varieties of nucleic acids that aid in the process passing on this information to the next generation: DNA and RNA. The DNA encodes the information that is used to assemble proteins while the cells use RNA to read the cell's DNA encoded information and direct the synthesis of proteins. The RNA then passes out into the rest of the cell, where it serves as a blueprint specifying a protein's amino acid sequence.

Nucleic acids are made out of monomers which are called nucleotides. There are three parts to nucleotides: a nitrogen base (C-N ring), pentose sugar (5C), and a phosphate group. The pentose sugar is different in both DNA and RNA in that RNA has ribose while DNA has deoxyribose which means without sugar. Now the phosphate group is highly electronegative because it has oxygen and is a charged particle. So nucleic acids are highly charged molecules making them hydrophilic and not fearing water. Now there are two types of nucleotides: purines and pyrimidines. Purines are large, double ring molecules found in both DNA and RNA. Purines are adenine and guanine. Pyrimidines are smaller, single-ring molecules and they are cytosine, thymine, and uracil.

Before we go on to the building of the polymer, we should talk a little about DNA and RNA. DNA is a double nucleotide chain in that the N bases bond in pairs across chains. The double chains in DNA wind around each other and create a double helix. RNA on the other hand is a single nucleotide chain in where the nitrogen base dangle offs and is not connected to another nitrogen base. DNA and RNA both contain adenine, guanine, and cytosine but DNA has thymine while RNA has uracil.

Now we should talk about the nucleic polymer. The backbone of the nucleic acids contains a sugar to phosphate bond. When new bases are added to the sugar of the previous bases, a phosphodiester bond forms between them. To made the bond we need the enzyme called DNA or RNA polymerase. The nitrogen bases hangs off the sugar-phosphate backbone and this is important because this allows us to make compliments from the nitrogen base that is exposed; allows us to have a template. Nucleotides bond between the DNA strands in specific pairings. A purine bonds with a pyrimidine and a hydrogen bond forms between them. Now there is a specific pairing in that adenine bonds to thymine in DNA or adenine bonds to uracil in RNA, and guanine bonds to cytosine. A 2 hydrogen bonds forms between adenine and thymine and a 3 hydrogen bond forms between guanine and cytosine. The hydrogen bonds between the nucleotides join the 2 strands together. Ratio of A-T::G-C affects the stability of the DNA molecule like in higher temperature there are more G-C than A-T because G-C contains and 3 hydrogen bond which is stronger than 2 bonds.

Well we are finally finished with biochemistry but we are not finished with sherpa reports and our next sherpa is Sarah.

"I did my homework and became who I am today because I did my homework." (yea right)

Protein's Cont'd

Hey guys, well I know the structure of proteins is kind of difficult to learn, but I will try to do the best I can to help you guys understand this.

The primary structure is basically the order of amino acids in chains. Even a slight change in the amino acid can affect a protein's structure and then FUNCTION. One protein can determine the difference between sickle cell anemia and the normal red blood cells.

The secondary structure is local folding. This folds along short sections of polypeptide. They are hydrogen bonds between each R groups.

The dotted lines between the diagram are hydrogen bonds.

The tertiary structure is also known as whole molecule folding. This is determined by interactions between R groups. Hydrophobic bonds want to stay away from water so they cluster together so that the hydrophobic bonds are next to each other, clustered together. This is important in the structure of the the cell membrane. The hydrophobic tails basically face each other in a cell membrane, away from the water and cluster together, while the heads are hydrophylic and face the water. This forms a phospholipid bilayer.

The quaternary structure is when more than one polypeptide chain is joined together. However, it is important to note that not all proteins have subunits and more than one polypeptide. This polypeptide take different shapes and this then determines their functions. Its basically HYDROPHOBIC INTERACTIONS.

The unfolding of a protein has a fancy name for it called denaturing. When a protein unfolds, the tertiary structure, or 3' structure is disrupted. The pH, otherwise the acidity, is one of the factors. Another is salty environment, as well as temperature. Size doesn't matter, shape matters. Denaturing of proteins disrupts the H bonds, ionic bonds, and disulfide bridges. Ms. Foglia had boiled milk and added vinegar. Vinegar is an acid which disrupting the shape of the proteins. And believe it or not, it is the process of making cheese!!!

Proteins

Proteins

The most important job of a cell is to make proteins. Proteins are made in the ribosomes of a cell. Protiens are used for almost anything. They have many different structures, with each different structure having a different function. They are also known as multipurpose molecules.






Some examples of proteins are keratin and collagen which makes up hair nails and skin.

Proteins are made of two structures monomers and polymers. Monomers are amino acids, and there are 20 different ones. Polymers are polypeptides. Proteins can be one or more polypeptide chains that are folded and bonded together. They are large and complex molecules.

The structure of amino acids have a central carbon, and amino acid groups. The carboxyl group are acids. The R group is a side chain. This is a variable group confers unique chemical properties of the amino acids.

Nonpolar amino acids are nonpolar and hydrophobic. Nonpolar meaning there are carbons in it. Hydrophobic means that it does not like water so it tends to try and push the water away. On the other hand amino acids can be polar and hydrophilic. By polar it means that it has a nitrogen in it. Hydrophilic means that it likes water and wants to be in or as near as possible to water as it can. They are polar and hydrophilic because they fold in order to make a protein.

Sulfur containing amino acids allow a link between sulfers and amino acids to be created called disulfide bridges. It smells like rotten eggs or permed hair.

Peptide bonda are building proteins that link the NH2 of one amino acid to COOH of another. Part of the buildin proteins are polypeptide chains that involve N-terminus= NH2 end and the C- terminus which ends in a COOH.


One of the four levels of structure is primary (1 degree) stucture pattern. The DNA of the gene decides the amino acid sequence and even a slight change in the sequence can make it a change in the protein's stucture and funtion. The perfect example of this is Sickle Cell Anemia, where the structure of the cell of hemoglobin goes from a 'doughnut' shape to one that looks like a 'sickle' or 'cresant moon'.

Carbohydrates !

Ahhh yes Per. 1&2
It is time to unveil my most devious plan everr, preparations A through G were complete failures... but now it is time to initiate.... Preparation H.







On Friday we had the wonderful opportunity of learning all about my good friend, the standard Carbohydrate. Now mah boy "carbohydrate" means a "hydrate of carbon.” Back in college him hydrogen and oxygen were near inseparable with a 1:2:1 ratio..

"I’d say they were pretty tight"

Now the general formula of carbohydrate Cx (H2O) y - x and y may or may not be equal and range in value from 3 to 12 or more.

For example glucose is: C6 (H2O) 6 or is more commonly written, C6H12O6.The chemistry of carbohydrates most closely resembles that of alcohol, aldehyde, and ketone functional groups. The chemistry of carbohydrates is complicated by the fact that there is a functional group (alcohol) on almost every carbon. In addition, the carbohydrate may exist in either a straight chain or a ring structure.
A major part of the carbon cycle occurs as carbon dioxide is converted to carbohydrates through photosynthesis. Carbohydrates are utilized by animals and humans in metabolism to produce energy and other compounds.

Carbohydrate Functions:
Carbohydrates are initially synthesized in plants from a complex series of reactions involving photosynthesis.
-Store energy in the form of starch (photosynthesis in plants) or glycogen (in animals and humans).
-Provide energy through metabolism pathways and cycles.
-Supply carbon for synthesis of other compounds.
-Form structural components in cells and tissues.

Photosynthesis:
Is a complex series of reactions carried out by algae, phytoplankton, and the leaves in plants, which utilize the energy from the sun. The simplified version of this chemical reaction is to utilize carbon dioxide molecules from the air and water molecules and the energy from the sun to produce a simple sugar such as glucose and oxygen molecules as a by product. The simple sugars are then converted into other molecules such as starch, fats, proteins, enzymes, and DNA/RNA i.e. all of the other molecules in living plants. All of the "matter/stuff" of a plant ultimately is produced as a result of this photosynthesis reaction.

Metabolism:
Metabolism occurs in animals and humans after the ingestion of organic plant or animal foods. In the cells a series of complex reactions occurs with oxygen to convert for example glucose sugar into the products of carbon dioxide and water and ENERGY. This reaction is also carried out by bacteria in the decomposition/decay of waste materials on land and in the water.
Combustion occurs when any organic material is reacted in the presence of oxygen to give off the products of carbon dioxide and water and ENERGY. The organic material can be any fossil fuel such as natural gas oil, or coal. Other organic materials that combust are wood, paper, plastics, and cloth.

The whole purpose of both processes is to convert chemical energy into other forms of energy such as heat.

The monomers of carbohydrates are called monosaccharides and are also called simple sugars. They are usually ring-like and are composed of five or six carbons. They are either a polyhydroxy aldehyde or a polyhydroxy ketone, which means they have more than one hydroxide group (-OH) and one carbonyl group (C=O). Some popular monosaccharides are glucose, fructose, and galactose.However, some very important carbohydrates are composed of thousands of monomers and are called polysaccharides. Here are the main important polysaccharides:- starch: Plants store their energy as starch using photosynthesis. We eat plants, breaking down the starch into its monomers and putting it to good use.- cellulose: The cell walls around plants are composed of cellulose. Cellulose is a very important structural component of plants and it's what makes them snap when you rip them apart. Err, I mean - they provide support for the plant.- glycogen: Animals store energy as glycogen. It's stored in the liver.

A carbonyl group is a functional group composed of a carbon atom double bonded to an oxygen atom : C=O.

An aldehyde is an organic compound containing a terminal carbonyl group. This functional group which consists of a carbon atom which is bonded to a hydrogen atom and double bonded to an oxygen atom (chemical formula O=CH-), is called the aldehyde group.

A ketone (pronounced as key tone) is either the functional group characterized by a carbonyl group (O=C) linked to two other carbon atoms or a chemical compound that contains this functional group. A ketone can be generally represented by the formula:
R1(CO)R2.


Cellulose:
The major component in the rigid cell walls in plants is cellulose
(Fat B@$tard also seems to be composed of a similar substance)

Cellulose is a linear polysaccharide polymer with many glucose monosaccharide units. The acetal linkage is beta which makes it different from starch. This peculiar difference in acetal linkages results in a major difference in digestibility in humans. Humans are unable to digest cellulose because the appropriate enzymes to breakdown the beta acetal linkages are lacking. Indigestible cellulose is the fiber which aids in the smooth working of the intestinal tract.
Animals such as cows, horses, sheep, goats, and termites have symbiotic bacteria in the intestinal tract. These symbiotic bacteria possess the necessary enzymes to digest cellulose in the GI tract. They have the required enzymes for the breakdown or hydrolysis of the cellulose; the animals do not, not even termites, have the correct enzymes. No vertebrate can digest cellulose directly.

Compare Cellulose & Starch Structures:
Cellulose: Beta glucose is the monomer unit in cellulose. As a result of the bond angles in the beta acetal linkage, cellulose is mostly a linear chain.
Starch: Alpha glucose is the monomer unit in starch. As a result of the bond angles in the alpha acetal linkage, starch-amylose actually forms a spiral much like a coiled spring.

I leave you with the mugshots of two alleged carb jackers

(Known only as Moonshine the Hippie & Lil Red) previously taken into custody for posession of carbs with intent to distribute.

Although uneasy on the eys I urge to look beyond the mundane and horror to identify these criminals for whoever does... would most worthy of tomorrows sherpa report!

Chemistry of Carbon

Today we learned about Carbon, which just reinforces the idea presented in Paiges post about how terrible Chemistry really is.

- All life is built on carbon. Cells are made up of 72% water, 25% carbon, and 3% Salt.



That is us, mostly made of water.
- And thats the carbon we're made of!

• First off theres the BIG 4: Carbohydrates, Lipids, Proteins, and Nucleic Acids
  

Carbon atoms are very versatile building blocks because they equally share electrons with hydrogen. They have 4 stable covalent bonds.

Hydrocarbons are combinations of carbon and hydrogen. They are non-polar, hydrophobic (fear of water), stable, and are gases at room temperatures. They are gases because there is no close attraction between the molecules so therefore they stay far apart.

• Isomers: are molecules with the same molecular formula but different structures or shapes.

*Form affects function!*
Small structural differences can create important functional significance. For example the amino acid alanine has an L-version and a D-version. They are mirror images of each other and are called stereoisomers. In medicine, only the L-version is active and this is important to know because of tragic effects such as in the case of Thalidomide. It was intended to reduce morning sickness but instead caused severe birth defects in limb development.

Diversity of Molecules :
Substitute other atoms or groups around the carbon. Ethane can become Ethanol (alcohol) when an H is replaced by a hydroxyl group (-OH). This change makes ethane non-polar, and ethanol polar, and ethane a gas while ethanol is a liquid. Below is an example of what ethanol can do to you and your belly.

• Functional Groups are parts of organic molecules that are involved in chemical reactions. These groups are hydroxyl, carbonyl, carboxyl, amino, sulfhydryl, and phosphate. These groups are all the difference in the case of female and males. They have the same carbon skeleton but different functional groups are attached and one becomes estrogen while the other is testosterone.

Macromolecules- smaller organic molecules join together to form larger molecules. The big 4 are the major classes of macromolecules.
-Polymers are long molecules built by linking repeating building blocks in a chain.
-Monomers are small building blocks.

Building Polymers

• Dehydration (Condensation) Synthesis: a water molecule is removed
• - one monomer donates OH- and another donates H+, these two combine to form H2O
  

Breaking down Polymers

• Digestion (Hydrolysis) - use H2O to break down polymers. The water is split into H+ and OH-
• Requires Enzymes
  

Carbon are the building blocks of life, so I guess I dont hate them after all<3 Tom and the lunchbox are the next sherpas.

the Good, the Bad, and the BIOCHEMISTRY!
We all took chemistry over the past two years and it was terrible and its back.

We spent the entire period studying the properties of water which are super important because all life occurs in water, inside and outside of the cell.

COHESION AND ADHESION
COHESION: H bonding between water molecules

-just like Tom and his girl pictured above, water likes to stick together. That’s why we can suck it up through a straw.

- water has an extremely high surface tension, so that’s why not a lot of organisms can walk on it, except for Jesus and insects like the water strider of course. The strider’s impact on the water is less than H2O’s surface tension so they don’t sink.

ADHESION: H bonding with H2O and other substances
Ex: capillary action, meniscus, water on paper towel

SO LETS APPLY THESE TO REAL LIFE: trees.
Trees are built on cohesion and adhesion. The stomates on the tree’s leaves open to allow water molecules to evaporate. As one molecule leaves the leaf, it pulls another water molecule along, and it continues.

-polarity makes H2O a stellar solvent because water molecules surround positive and negative ions.
-hydrophilic and polar: DISSOLVE IN WATER
-hydrophobic and non-polar: SEPERATES FROM WATER (no attraction)

ICE ICE BABYYY.

All substances are denser as a solid right? NOPE, not water. Ice floats!
-At 4 degrees Celsius, water is at its densest.

So why is floating ice so important in real living things?
When lakes freeze over, the surface ice insulates the water below it making it possible for fish and other organisms to live through winter. Floating Ice also attributes to the cycling of nutrients.

FOGLIA ICE TIP OF THE DAY:
Make sure you always mix your drinks at the bar,

this way you never have to drink a weak mix, and you save cash!

SPECIFIC HEAT: how much energy is required to heat a substance
-water has a very high specific heat. It takes more to heat up and cool down water than anything else.
-specific heat’s important because H2O moderates all temperatures on earth.
-areas surrounded by land: extremes (super hot in summer, freezing in winter)
-areas near water: moderate temperatures year round

IONIZATION OF WATER AND pH
1. if H+ = -OH then water is neutral
2. if H+ > -OH then water is acidic
3. if H+ < -OH then water is basic

These three points make up the base of the pH scale

pH Scale- how acidic or basic a solution is measured on a 1 through 14 scale

1 being super acidic, 14 being super basic, 7 is neutral

Buffers- chemicals that allow control of pH measure

Lastly, here are a couple of lameo macaques

On Monday, we learned about the chemistry of life. Although this is an AP Biology class, we study chemistry because it is the foundation of Biology.

As many of us have learned across the hall in the Chemistry rooms, everything is made of matter. Matter is made of atoms that are made up of electrons, protons and neutrons.
In this biology course, we only need to worry about ten elements on the periodic table: hydrogen, magnesium, potasium, sodium, calcium, carbon, nitrogen, oxygen, phosphorus and sulfate. Hydrogen, carbon, nitrogen, and oxygen are the key elements that our human body is made up of. Phosphorus is in DNA and ATP.

We also went on to learn about the bonding properties and the effect of electrons. Electrons determine the chemical behavior of an atom, depending on the the number of electrons in an atom's outermost shell. The valence shell is nonactive.
Atoms with many electrons in its valence shell have high electronegativity and tend to want to "steal" electrons from other atoms while atoms with fewer electrons have low electronegativity in their valence shell and tend to want to "donate" to other atoms. These atoms with fewer electrons donate bececause they cannot hold that many electrons themselves. These tendencies drive chemical reactions and create bonds. A chief principle that we learned Monday was that when we think of weak bonds, hydrogen bonds should be the very first thing we think of while when strong bonds are mentioned, covalent bonds should be thought of immediately. Covalent bonds are strong because two atoms share a pair of electons and both atoms hold onto the electrons, making them very stable. This forms molecules. The more pairs of electrons shared, the stronger the bond. More is better!


PAGEMASTER will be our next sherpaaaaa!

And That's The Way The Cookie Crumbles!

IMPORTANT NOTE: The following post does not reflect the views of it's author. It is simply reflective of what we learned in class, and the information provided is not supported by it's provider.

Welcome folks, to another exciting round of Biology Jeapordy with your host....

The wonderfully talented (and good looking!) Alex Trebek!

So basically, today in class we covered Critical Periods, Various Animal Behaviors (operant and classical conditioning), Social Behaviors, and BioMagnification. So our categories will be.....

1) Critical Periods 2) Various Animal Behaviors 3) Social Behaviors and.....

4) BioMagnification-----surprise!

CRITICAL PERIODS

So, what are these things anyway?

Critical periods are just what they sound like: critical periods of time in which an organism is expected to learn something, which can usually only be learned within the critical period.

For example, language in humans is learned during a critical period. Children who don't learn to speak within this critical period aren't usually able to grasp the complexity of our language.

Critical periods are interesting, aren't they? Why can an organism learn to do something at one period in their life, but not after that? Like they say, you can't teach an old trick a new dog. Or something like that.

Various Animal Behaviors

To easily understand how and why animals act the way they do, it's best to split the topic up into two sections:

1) Innate Behaviors (or instinctive behaviors)
2) Learned Behaviors

While I would love to take the time to explain both to you, I'm not going to! We learned about learned behaviors today, and innate behavior yesterday. So if you need help on innate, consult Sean's post.

--Learned Behaviors--

Learned behaviors are behaviors that organisms learn throughout their lives. For example, most species of birds learn their song from their parents and the birds around them.


When studying learned behaviors, it is imperative that you know the following terms.

Associative Learning-learning to associate one feature of the environment with another.

Operant Conditioning-trial and error learning; associating behavior with reward or punishment.

Classical Conditioning-Associating a "neutral stimulus" with a "significant stimulus"

Operant Conditioning is easy enough to remember. Just think about Skinner's box, and the mouse's repeated action of pressing the lever to get food.

After pushing the lever for the first time (and every time after that), the mouse gets a piece of food. The mouse then learns to associate the act of pushing the lever with a reward.

The ingenious man who came up with this experiment was B.F. Skinner.

Classical Conditioning should be no problem for us AP students either! Just think about Ivan Pavlov and his experiments with the dog and the bell.

Before each time Pavlov fed the dog, he rang a bell. Then, by just ringing a bell, he could get the dog to salivate, expecting food. This experiment demonstrates classical conditioning because the dog is connecting a reflex behavior (salivating at the sight of food) to associated stimulus (the ringing bell).

Let's give it up for Ivan Pavlov!

(Ivan Pavlov)^^^

Next we should talk about Social Behaviors.

Social Behaviors

To understand the social behaviors of animals, we should know:

Habituation-loss of response to stimulus (think of "The Boy Who Cried Wolf", in which animals learn not to repond to repeated occurrences of stimulus).

--Language--
Many animals use some form of language to communicate. Communication between individuals is necessary for mating, protection, and finding food.

Examples of language in animals are the songs birds use to find mates, and the honey bee's waggle dance.

--Agonistic Behaviors--
Agonistic behaviors are behaviors that animals perform to outcompete others. These behaviors are generally not threatening, but are instead ritualistic behaviors performed to impress mates, and to establish a social rank.

--Altruistic Behaviors--
Altruistic behaviors are behaviors which are performed which reduces individual fitness but increases fitness of recipient.

A perfect example of this is found in the Belding ground squirrel. These crazy squirrels make noise when predators are near, endangering themselves but incresing the chance of survival of their families and offspring.

The next important thing to understand is the concept of pheromones.

--Pheromones--
Pheromones are chemical substances that stimulate a response from other individuals. The most common pheromone types are alarm pheromones and sex pheromones.

These are vital to the animals success, protection, and reproduction.



So the next time that sweaty person stting next to you smells of bad B.O., just think....

...is this disgusting, or seductive?

--Cooperation--

Some animals cooperate with eachother to help get food, protection, or resources. This can best be associated with a mutualistic symbiotic relationship, because both individuals benefit.

Examples of cooperation include:

1) African dogs who hunt together in packs to help bring dow prey more quickly.

2) White pelican and dolphins who "herd" fish to make it easier for the whole group to eat.

--Colonial Mammals--

Colonial mammals are those who have a queen, breeding and non-breeding workers, and a whole social heirarchy.

Some examples of these include:

1) Bees

2) Ants

3) Termites

4) Mole Rats

And since mole rats are all your favorite animals to look at.....

And now....... (finally)

BioMagnification

BioMagnification is a pretty easy concept to grasp. Basically, it's just the idea that if a substance is introduced to an organism on the bottom of the food chain, then it will increase in concentration as it travels up the food chain. This is due to the fact that a secondary consumers eat several primary consumers, and get more of a concentration of the substance. In turn, tertiary consumers eat more than one of the secondary consumers, and obtain an even greater concentration of the substance.

So the overall lesson of this post? There is a reason why animals act the way they do, and it's important to know the reason.

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