New User Special Price Expires in

Let's log you in.

Sign in with Facebook


Don't have a StudySoup account? Create one here!


Create a StudySoup account

Be part of our community, it's free to join!

Sign up with Facebook


Create your account
By creating an account you agree to StudySoup's terms and conditions and privacy policy

Already have a StudySoup account? Login here

Physiology Week 2 notes

by: Alesa Taylor

Physiology Week 2 notes 3014

Marketplace > Mississippi State University > 3014 > Physiology Week 2 notes
Alesa Taylor
GPA 3.57

Preview These Notes for FREE

Get a free preview of these Notes, just enter your email below.

Unlock Preview
Unlock Preview

Preview these materials now for free

Why put in your email? Get access to more of this material and other relevant free materials for your school

View Preview

About this Document

Finishes chapter 2 and the part of chapter 3 covered in class
Human Physiology
James Stewart
Class Notes
25 ?




Popular in Human Physiology

Popular in Department

This 7 page Class Notes was uploaded by Alesa Taylor on Friday January 22, 2016. The Class Notes belongs to 3014 at Mississippi State University taught by James Stewart in Spring 2016. Since its upload, it has received 29 views.


Reviews for Physiology Week 2 notes


Report this Material


What is Karma?


Karma is the currency of StudySoup.

You can buy or earn more Karma at anytime and redeem it for class notes, study guides, flashcards, and more!

Date Created: 01/22/16
1/19/16  Electrical energy- combination of potential and kinetic energy- movement of charged particles along a diffusion gradient—the separation of charges (positive and negative) across a membrane o When ion channels open, the charged particles(ions) go across the membrane along the diffusion gradient( from higher concentration to lower concentration until the channel closes or both sides reach equilibrium and become even) this movement is where kinetic energy happens  Diffusion gradient- a difference between two points ex. Concentration  Diffusion- when molecules disperse randomly in the available space, from the high concentration to areas of low concentration o it governs many biological processes o leads to random distribution of molecules because the molecules are constantly bumping into each other and changing directions, so at any moment it could be moving in any direction, making their movements completely random o source of energy that can be used to drive other processes  ex. Of diffusion: when everyone leaves class they go from an area of high concentration in the classroom to an area of low concentration outside the classroom  Gradients are a form of energy storage o Example: Potential energy  Organisms invest energy to delay diffusion/ to slow rates of diffusion  Gradients across membranes can be chemical, electrical, or both (electrochemical)  Thermal energy- only kinetic energy, the movement of the molecules increases the overall temperature  If thermal energy is increased… o Molecules move faster o Chemical reaction rates become faster  Free energy (G)- the energy available to do work  Activation energy (A )- energy required to reach the transition state  Transition state- the intermediate structure between a substrate and a product o The higher the curve to reach transition state, the more energy has to be used to reach the product  Change in free energy (∆G) = productssubstrates o Exothermic: ∆G is negative o Endothermic: ∆G is positive  Most chemical reactions involve changes in thermal energy  Exothermic reactions- release heat (heat EXits the equation)  Endothermic reactions- take heat in (heat goes “EN” to the equation)  Enzymes- Protein molecules acting as protein catalyst o Lower the activation energy for biological reactions so that they can have a faster reaction rate and make more products  To function, enzymes must come into contact with reactants called substrates  The substrate binds to the enzyme, forming an enzyme-substrate complex, which then breaks down to release products and enzyme.  There are two types of enzyme-substrate models: “lock-and-key” and “induced fit” o Lock-and-key suggests that the enzyme is in the exact shape to take on the substrates—like a puzzle o “induced fit” suggests that the enzyme is a general shape and moves to fit around the substrate when it joins  Remember- the body is greedy it will do whatever it has to in order to use minimal energy to gain maximum output  Enzymes do not change the chemical equation and the chemical process does not affect the enzyme  Enzymes are also known as biological catalysts—they are active at low concentrations, increase the reaction rate, are not changed by the reaction, do not change the nature of the products  Some contain non-protein components such as cofactors which covalently bind to the enzyme— they are usually made up of heavy metals like copper or iron—another non-protein component is organic coenzymes which are usually made up of vitamins  Oxidation-Reduction Reaction: Add or subtract electrons o Most important in energy extraction and energy transfer in cells  Oxidation- transfer electrons from donor to oxygen (oxygenase)—remove electrons and hydrogen from the donor using dehydrogenase—like rust on iron  Reduction- gain electrons (reductase) adding negatively charged electrons will reduce the electric charge  If it ends in –ase it is an enzyme  Hydrolysis-Dehydration Reaction: Add or subtract water o Most important in breakdown and synthesis of biomolecules  Hydrolysis- splitting large molecules by adding water—peptidases break down peptides, lipidases break down lipids, saccharidases breakdown sugars—all elements of the digestive system  Dehydration- remove water to make larger molecules from several smaller molecules- dehydrates making longer molecules  Addition-Subtraction-Exchange Reactions: Transfer chemical groups between molecules o Most important in signal transduction  Addition reaction- adds a functional group (a phosphate group ex. Phosphorylase)  Subtraction reaction- removal of a functional group (phosphatase)  Exchange reactions- functional group (ATP) is exchanged between substrates (kinase)  Ligation Reactions: Joining of two substrates (synthesis) using energy from ATP  Synthetases or ligases  Metabolism: All chemical reactions that take place in an organism. o Extracts energy from nutrient biomolecules o Synthesizes the breakdown of molecules o Catabolism- releases energy through the breakdown of large biomolecules o Anabolism- uses energy to synthesis large biomolecules  Enzyme-mediated reactions- regulated by three major factors- 1. Substrate concentration 2. Enzyme concentration 3. Enzyme activity—if any of these factors are altered the amount of product will change  Chemical energy- potential energy held within chemical bonds  Most biologically available energy is stored in chemical bonds  Two main types of bonds: covalent and noncovalent  Covalent bonds- the strongest, atoms share an electron  Noncovalent bonds- weakest, molecules are arranged in a three dimensional (3-D) formation held by electron static attraction  the stronger the bond the more energy it will have  Atoms with unpaired electrons are available to form covalent bonds with unpaired electrons from other atoms  Atoms with more than one unpaired electron can form multiple covalent bonds  Bond energy – amount of energy needed to make or break the bond (chemical energy)  Functional groups – combinations of atoms and bonds that recur in biological molecules o Common in biological macromolecular structures  Control macromolecule structure  Often responsible for maintaining 3D structures  Arise between atoms with unequal distribution of electrons  Sensitive to temperature- denature  Four types: 1. Van der Waals Forces 2. Hydrogen bonds 3. Ionic bonds 4. Hydrophobic bonds o Van der Waals is the weakest of the four types o Water is a good example of a hydrogen bond  Van der Waals interaction are conducted when an atom with transient dipole affects the distribution of electrons in another atom o Transient dipole – polarity created by asymmetry of electron distribution within an atom o Effective only over a narrow range of distances  Hydrogen bonds are the asymmetric sharing of electrons between two atoms  Hydrogen (+) of one molecule is attracted to the (–) of another  Ionic bonds are made from ions, an ion is an atom or molecule that has gained or lost one or more electrons o They have a net electric charge  Cations- net positive charge  Anions- net negative charge  Ionic bond occurs when a cation binds to an anion o Example: salts, acids, and bases  Hydrophobic bonds are formed due to mutual aversion (“phobia”) to water o Molecules tend to share electrons equally  Do not have significant dipoles with little internal charges  Cannot interact with polar water molecules  Properties of water: Water is a network of interconnected molecules attracted to each other by hydrogen bonds  Surface tension – the force due to attraction between water molecules at the water–air interface  Solvent- liquid in which molecules are dissolved  Solute- molecules dissolved in solvent  Solution- combination of solvents and solutes  In biological systems the solvent is usually water  Colligative properties: 1. Reduced freezing point 2. Increased boiling point 3. Increased vapor pressure 4. Osmotic pressure (osmosis is the movement/diffusion of water) o Depends on the number out solutes o Not dependent on their size or charge 1/21/16  Direction of diffusion depends on the concentration gradient  Rate of diffusion depends on many factors o Size of concentration gradient (dC/dX) o Size of molecule used to calculate the diffusion coefficient (Ds) o Diffusion area (A)  Increase the size of any of the above and the diffusion process will happen faster. Ex. A room full of beach balls will empty faster than a room full of marbles because there will be fewer beach balls in the room.  The rate of diffusion obeys Fick’s law: Diffusion Rate=Ds* A*dC/dX  Within a living cell, all of the molecules, ions, and particles combine to produce a total osmotic pressure  Osmosis- the diffusion of water across a semi-permeable membrane (allows some particles to cross but not others)  Osmotic pressure- force associated with the diffusion of water  Osmolarity (OsM=M)- the ability of a solution to cause water to diffuse across a membrane o Determined by the concentration of dissolved particles o Water move towards wherever has the most particles (like when tea is too strong and you have to “water it down” so you put in more water to make a less concentrated amount of tea particles)  Any solution that contains an equal number of osmotically active particles will produce the same osmotic pressure as that produced by the constituents- isotonic- meaning “same tension” will produce no change in the size due to the net water inside the cell (same concentration of water inside the cell as there is outside the cell so it isn’t gaining or losing water)  Hypertonic solution is one that exerts a greater osmotic pressure than the cell contents  Hypotonic solution produces a lower osmotic pressure than within the cell  Hyp”e”r and hyp”o”, o is a swelling cell so water is going into it, e is a shrinking cell so water is going out of it  Organic chemistry is the study of carbon containing molecules  Inorganic chemistry is the study of non-carbon containing molecules  Biochemistry is the chemistry of living organisms  Classes of organic molecules o Carbohydrates  Monosaccharides  Disaccharides  Polysaccharides o Lipids  Fatty acids  Triglycerides  Phospholipids—vital part of the cell membrane  Steroids o Protiens  Amino acid subunits  Polypeptides  Enzymes o Nucleic acids  DNA  RNA  Lipids are molecules composed predominantly(but not exclusively) of hydrogen and carbon atoms  These atoms are linked by nonpolar covalent bonds and have very low solubility in water  Triglycerides (also known as triacylglycerols) constitute the majority of lipids in the body o Form when glycerol, a 3-carbon alcohol, bonds to three fatty acids o Found in all cells and comprise part of cellular membranes, including those of intracellular organelles  Phospholipids are similar in overall structure to triglycerides but the third hydroxyl group of glycerol is linked to phosphate  Amphipathic- possessing both hydrophilic( water-loving, polar) and lipophilic( fat-loving) properties  Steroids- four interconnected rings of carbon atoms form the skeleton of every steroid, they are not water soluble  Proteins- proteins account for about 50% of the organic material in the body o 17% of body weight o Critical roles in almost every physiological process o Proteins are composed of carbon, hydrogen, oxygen, nitrogen, and small amounts of other elements (CHON)  Amino acids- the subunit monomers of proteins are amino acids o Every amino acids except proline has an amino (-NH2) and a carboxyl (-COOH) group bound to the terminal carbon atom in the molecules o The proteins of all living organisms are composed of the same set of 20 different amino acids, corresponding to 20 different side chains o The side chains may be nonpolar( 8 amino acids), polar( 7 amino acids), or ionized( acidic/basic 5 amino acids) o The human body can synthesize many amino acids( non-essential) o Several must be obtained in the diet and are known as essential amino acids  Nucleic acids have two classes: deoxyribonucleic acid( DNA) and Ribonucleic acid( RNA) o DNA molecules store genetic information coded in the sequence of their genes o RNA molecules are in charge of decoding the information from DNA into instructions for the body to carry out  DNA making more DNA is replication  DNA being turned into RNA is transcription  RNA being converted into protein is translation  DNA is made up of four different nucleotides, corresponding to the four different bases that can be bound to deoxyribose o The bases are divided into two classes:  Purine which is adenine and guanine; they are made of double rings of nitrogen and carbon  Pyrimidine which is cytosine and thymine; they have single rings of nitrogen and carbon  Adenine pairs with thymine  Guanine pairs with cytosine  RNA molecules are only different from DNA in a couple of ways o RNA is a single chain of nucleotides o In RNA the sugar in each nucleotide is ribose rather than deoxyribose o The pyrimidine base thymine is replaced with uracil (adenine pairs with uracil, guanine pairs with cytosine) Chapter 3  There are two major cavities in the body.  Cavity- closed to the outside and contains internal organs  Dorsal body cavity (2 subdivisions)- cranial cavity which contains the skull, vertebral cavity which contains the vertebral column and encloses the spinal cord  Ventral body cavity- larger cavity; contains the visceral organs- thoracic cavity and the abdominopelvic( peritoneal) cavity  Thoracic cavity- divided into three parts o Pleural cavity- 2 lateral parts each containing a lung o Mediastinum cavity- central band of organs o Pericardial cavity- surrounds the heart  Abdominopelvic cavity- divided into parts, but continuous o Abdominal cavity- superior cavity, contains the liver, stomach, kidneys and other organs o Pelvic cavity- inferior cavity, contains bladder, reproductive organs, and the rectum  There are two types of membranes in the body o Macrostructures- membranes the cover anatomic tissue structures ex. The pericardial membrane o Microstructures- membranes that cover cellular and subcellular structures ex. The phospholipid cell membranes  Creates cellular compartments within the tissue  Creates a level of physiological control  Plasma (cell) membrane- exterior structure, protective barrier  Cytoplasm (cytosol)- intracellular fluid  Cell organelles- membrane bound compartments with special functions  Nucleus- contains genetic material  Cell membrane- 1. Physically separates intracellular fluid inside the cell from surrounding extracellular fluid 2. Regulates what is exchanged with the environment (ions, nutrients, release of products, cellular waste) 3. Communicates between the cell and environment (embedded proteins that recognize and respond to molecules or changes in the external environment, alters the activity of cells) 4. Supports cells structurally using scaffolding to maintain shape (scaffolding- specialized cell-to-cell and cell-to-extracellular matrix junctions to maintain tissue structure)  Membrane structure- consists of a double layer of lipid molecules- major membranes are phospholipids which are amphipathic, polar on the outside, and nonpolar on the inside, they also contain cholesterols and embedded proteins  There are two classes of membrane proteins: o Integral membrane proteins- amphipathic, cannot be extracted from the membrane without disrupting the lipid bilayer, and have transmembrane proteins (proteins that go completely across the membrane) o Peripheral membrane proteins- not amphipathic, do not associate with the nonpolar regions of the lipids in the interior, located on the surface of the membrane o Cell junctions- desmosomes, tight junctions, and gap junctions  Desmosomes (adhesive junctions)- adhesive spot on the lateral sides linked by proteins/ filaments; holds tissues together  Tight junctions- at apial area, plasma membrane of adjacent cells fuse, nothing passes through the junction  Gap junctions- spot-like junction occurring anywhere, made of hollow cylinders or proteins; lets small molecules pass between cells o Membrane junctions: integrins- transmembrane, proteins control attachment between cells and the environment such as surrounding tissues, other cells, and extracellular matrix o Nucleus- primary functions include: storage and transmission of genetic information to the next generation of cells via replication, transcription, and translation o Endoplasmic reticulum (ER) – there are two forms of ER: smooth and rough  Rough ER controls protein packaging  Smooth ER synthesizes lipid molecules, detoxifies certain hydrophobic molecules, stores and releases calcium o Golgi apparatus- modifies and transports proteins received from the ER, transports vesicles to release outside of cell (vesicles containing proteins to be released outside of cells are called secretory vesicles) o Endosomes- membrane bounds vesicular and tubular structures between the plasma membrane and the Golgi apparatus, involved with sorting, modifying, and directing vesicular traffic in cells o Mitochondria- involved with transferring energy from chemical bonds to ATP, has a smooth outer membrane, and an inner layer that is folded into sheets and tubules called the cristae, the cristae extends in the compartments inside the organelle called the matrix, there are more mitochondria in cells that use a lot of energy than in cells that don’t use a lot of energy ( lots of mitochondria in muscle cells, very little mitochondria in lipid(fat) cells) o Lysosomes- spherical or oval shaped organelles surrounded by a single membranes, break down bacteria, damaged cells, and even damaged organelles, defend the body from things that make it act wrong—the garbage truck of the cells


Buy Material

Are you sure you want to buy this material for

25 Karma

Buy Material

BOOM! Enjoy Your Free Notes!

We've added these Notes to your profile, click here to view them now.


You're already Subscribed!

Looks like you've already subscribed to StudySoup, you won't need to purchase another subscription to get this material. To access this material simply click 'View Full Document'

Why people love StudySoup

Jim McGreen Ohio University

"Knowing I can count on the Elite Notetaker in my class allows me to focus on what the professor is saying instead of just scribbling notes the whole time and falling behind."

Kyle Maynard Purdue

"When you're taking detailed notes and trying to help everyone else out in the class, it really helps you learn and understand the I made $280 on my first study guide!"

Jim McGreen Ohio University

"Knowing I can count on the Elite Notetaker in my class allows me to focus on what the professor is saying instead of just scribbling notes the whole time and falling behind."

Parker Thompson 500 Startups

"It's a great way for students to improve their educational experience and it seemed like a product that everybody wants, so all the people participating are winning."

Become an Elite Notetaker and start selling your notes online!

Refund Policy


All subscriptions to StudySoup are paid in full at the time of subscribing. To change your credit card information or to cancel your subscription, go to "Edit Settings". All credit card information will be available there. If you should decide to cancel your subscription, it will continue to be valid until the next payment period, as all payments for the current period were made in advance. For special circumstances, please email


StudySoup has more than 1 million course-specific study resources to help students study smarter. If you’re having trouble finding what you’re looking for, our customer support team can help you find what you need! Feel free to contact them here:

Recurring Subscriptions: If you have canceled your recurring subscription on the day of renewal and have not downloaded any documents, you may request a refund by submitting an email to

Satisfaction Guarantee: If you’re not satisfied with your subscription, you can contact us for further help. Contact must be made within 3 business days of your subscription purchase and your refund request will be subject for review.

Please Note: Refunds can never be provided more than 30 days after the initial purchase date regardless of your activity on the site.