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

Biology week of 1/25

by: Audrey Notetaker

Biology week of 1/25 200001

Marketplace > Boston College > Biology > 200001 > Biology week of 1 25
Audrey Notetaker
GPA 3.9

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

These notes cover chapter 2 and 3 as well as what will be on the next quiz
Molecules and Cells
Danielle Taghian
Class Notes
25 ?




Popular in Molecules and Cells

Popular in Biology

This 6 page Class Notes was uploaded by Audrey Notetaker on Saturday January 30, 2016. The Class Notes belongs to 200001 at Boston College taught by Danielle Taghian in Spring 2016. Since its upload, it has received 33 views. For similar materials see Molecules and Cells in Biology at Boston College.


Reviews for Biology week of 1/25


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: 01/30/16
Chapter 2: Covalent Bonds and Weak Chemical Interactions  1/25/16 Elements in organisms:  99% C, N, O, H  0.9% P, S Cl, Na, Mg, K, Ca Four major small organic compounds in cells (macromolecules)  Sugars (carbohydrates) o Quick energy o Structural support o Form polysaccharide  Fatty acids  (lipids) o Long hydrocarbon chains o Cell membranes o Bigger long term energy  Amino acids (proteins) o Polymers form protein o Form protein  Nucleotides o Building blocks of RNA and DNA Macromolecule Monomer unit Covalent bond Nucleic acids (DNA, RNA) NUCLEOTIDE Phosphodiester Proteins Amino acids Peptide  Carbohydrate Monosaccharides Glycosidic bond Lipids (phospholipids and  Fatty acid and  Ester bond triglycerides) glycerol Covalent: sharing of electrons equally electronegative; stable; strongest bond  Single bond = free rotation  Double bond = no rotation Polar: slight electronegative difference, electron more towards O in H2O  Unequal sharing of electrons results in dipole (partial charges) Non polar: electrons equally shared, little electronegativity difference (lipids) Ionic: big electronegative difference (NaCl), transfer of electron(s); ions are formed Non covalent bonds: rely on attractive and intermolecular forces  Salt bridges: ionic interaction between salts: strongest  Hydrogen: H­O. H­N, H­F / electronegative atom attracted to another electronegative  atom o Two strands of DNA interact this way  Van der Waals: occasional dipole moments in non polar molecules; weakest Hydrophilic interactions ­ molecules interact with water via hydrogen bonds (polar) Hydrophobic ­ no interaction with water (non polar)  Insoluble in water; shields itself from water  Lipid bilayer Electronegativity: measure of the tendency of an atom to attract a bonding pair of electrons Chapter 2­3: Water and Carbon, Protein Structure and Function 1/27/16 Capillary Action: the ability of liquid to flow up a narrow tube against gravity Adhesive – molecules stick to the wall Cohesive – molecules stick to each other ­ if the adhesive force is greater than the cohesive, then the liquid will creep up the side  (i.e. water) ­ if the cohesive force is greater than the adhesive, then the liquid will bulge (i.e. mercury) *water has a high surface tension * Liquid water is more dense than solid ice ­ Ice: Hydrogen bonds are arranged in an open crystal pattern ­ water: fewer hydrogen bonds so liquid can pack more closely together Functional Groups Name & Structure Examples Properties Methyl lipids Nonpolar. Hydroxyl Alcohols and sugars Polar. Hydrogen bonds with water to help dissolve molecules. Enables linkage to other molecules by condensation. Carbonyl Sugars Polar. Contribute to making molecules water- soluble. Can be very reactive. Important in carbohydrates and energy releasing reactions. Carboxyl In fatty acids and Acidic. Ionizes in living tissues to form COO- + amino acids and H . Enters into condensation reaction by giving up -OH. Some carboxylic acids important in energy-releasing reactions. Amine Basic. Accepts H in living tissues to form + -NH 3 Enters+into condenstation reactions by giving up H . Phosphate Negatively charged. Enters into condensation reactions by giving up -OH. When bonded to another phosphate, hydrolysis releases much energy. Sulfyhydryl By giving up H, two -SH groups can react to form a disulfide bridge (S-S), thus stabilizing protein structure because it's a covalent bond. Amino acid The “R” group determines the function of the amino acid side chain Alpha Carbon: amino group, H, R, and carboxyl group is attached; central carbon atom Amino group ionizes to NH3+ and carboxyl group to COO­ which makes them more  reactive *know how to draw a hydrophobic, charged, and polar amino acid Chapter 3: Proteins  1/29/16 (Amine Bond) Peptide bond: condensation reactions bond the carboxyl group of one amino acid  to the amino group of another amino acid  Produces the bond + water  Electrons shared between carbonyl group and peptide bond allow for some double bonds *only alpha amino acids can form secondary structures (main/central carbon)   Protein:   Pieced with domains  Polypeptide: flexible and has directionality  Four levels of structure o Primary­ unique sequence of amino acids; just the code; determines 3D structure,  function  Has an amino end, and a carboxyl end, in the middle are amino acids  connected with peptide bonds  Changing one of the amino acids in the sequence can completely change  the structure and function of the protein. Does not always cause a change,  but change can be drastic (cancerous, sickle cell, etc.) o Secondary­ local confirmation of polypeptide chain; formed and stabilized by  hydrogen bonds  Each 360 turn = 3.6 aa at 1.5 A(angstroms) rise/aa; the peptide bond of  every 4th aa interacts via hydrogen bonds which are parallel o the axis of  the alpha helix while the aa side chains are perpendicular  Alpha helix ­ CO group forms hydrogen bond with NH every 4; mostly  found on outside of proteins  Met, ala, leu, glu, lys  Beta sheets­ often denoted by arrows  Consists of beta strands joined by hydrogen bonds formed between carbonyl and imine groups of neighboring backbones  Pleat is caused by the position of the alpha carbons above and  below the plane of the sheet  Tyr, phe, trp and thr, val, Ile and pro  Beta turn: allows peptide chain to reverse direction  Proline and glycine are more prevalent in beta turns  Random coils: no defined helix or beta sheet o Tertiary ­ interactions/intermolecular forces form to maintain overall structure of  protein  Get hydrophobic amino acids to the inside of the protein and get  hydrophilic amino acids to the outside so the protein can interact with  water  Results from o Quaternary ­ form follows function; two or more proteins interact with one  another  Two proteins = dimer  Four proteins = tetramer (hemoglobin)   Similar looking proteins may not have the exact same amino acid sequence (primary  structure)          


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

Steve Martinelli UC Los Angeles

"There's no way I would have passed my Organic Chemistry class this semester without the notes and study guides I got from StudySoup."

Amaris Trozzo George Washington University

"I made $350 in just two days after posting my first study guide."

Steve Martinelli UC Los Angeles

"There's no way I would have passed my Organic Chemistry class this semester without the notes and study guides I got from StudySoup."

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.