Question | Answer |
What is it called when it can be dissolved in water? such as NaCl | hydrophilic |
combination of two or more different elements | compound |
What are molecules? | -atoms held together by chemical bonds
-combination of two or more atoms |
nature of chemical bonds-_________ | electron interaction |
Name 3 types of bonds | -covalent
-ionic
-hydrogen |
What is a covalent bond? | -electrons are shared among the atoms w/in a molecule |
equal sharing in covalent bond | -nonpolar molecule
-such as 02 molecule (0=0) |
unequal sharing incovalent bond | -polar molecule
-such as H20 molecule (H-O-H)
-polar molecules can interact w/ each other
-important for solvent-solute interaction |
What are ions | -charged atoms or molecules |
List 3 characteristics of ionic bonds. | 1. electrons are transfered from one atom to another forming a positively charged cation and a negatively charged anion
2. two ions are held together by opposite charges
3. Ex: Na+ and Cl- forms strong interaction in salt (NaCl) via ionic bonds |
How does hydrogen bond occur? | hydrogen bond occurs between the small hydrogen atom and other bigger atoms (O&N in organic molecules) |
True or False hydrophilic molecules can interact with water molecules (e.g. NaCl) | True |
When salt dissolves in water ________ happens | -ionization (Na+ & Cl- ion are formed) |
How does ionization occur? | -ionic bonds broken up by the polar water molecules, producing separate anions and cations > salt is dissolved in water |
the solvent is __________
the solute is __________ | -water
-what you dissolved |
Is ethanol water soluble? Why? | yes, because (CH3CH2OH) it has an OH group which interacts with water
-many hydrophilic molecules are polar and can form H bond with water and these dissolve in water |
Why can't fat dissolve in water? | -because of the long carbohydrate chain
(CH3CH2CH2CH2......COOH)
-hydrophobic molecules do not form H bond with water molecules, therefore they "clump" in aqueous solutions |
What is quaternary ammonian? | -antimicrobial compound
-cationic deterents |
What does anionic detergent do? | -negatively charged head interacts with water
-tail inserts into the grease
-common households detergents |
How does cationic detergents work? | -disinfectants more important if charged hand is positive
-allows insert into membrane and kills bacteria |
amphipathic molecules all have what? | -charged head (hydrophilic)
-hydrophobic tail
- 2 types: anionic and cationic |
a higher concentration of H+ means what? | - higher acidity
- proton indicator of acidity more protons more acidity |
a higher concentration of OH- means what? | -higher alkalinity10 |
In pure water ionization of H2O releases ______ and ________ give formula | hydrogen ions (H+) and hydroxyl ions (OH-)
H20 >< H+ + OH-
[H+]x[OH-]=10^(-14) |
_______ is an invariable number at _______ no matter how acidic or alkaline the solution is. | 1. 10^(-14)
2. 25°C |
pH: 1.define it 2. If [H+]=10^(-5)M pH=______ 3.pH reflects concentration of _______ 4.normally pH scale ranges from _______ | 1.pH=-log[H+]
2.pH=5
3.H+ ions
4. 0 to 14 (or [H=] from 10^(1) to 10^(-14)) |
General rules of pH for neutral, acidic, and basic (3) | 1.Neutral=equal amounts of H= and OH- ions, pH=7
2. Acidic=more H+ ions then OH- ions in a solution pH<7
3.basic-more OH- ions than H+ in solution pH>7 |
Note: A low pH value gives a 1._________acidity (because of the 2.__________) 3.______fold difference in acidity when there is 1 pH unit change (because of the 4.________) | 1.higher
2.negative "-"
3.10
4."log" |
Test yourself:
pH6=
pH9=
pH7= | 10^(-6) moles H+/liter (M) acidic (10 fold more H+ than pH7)
10^-9 moles(M) H+/liter basic (100 fold less H+ than pH 7)
H+ and OH- conc. are the same, 10^(-7)M, neutral |
What is the fundamental element of life? | Carbon
-4 electrons in outer orbital
-forms single, double, or triple covalent bonds
-forms linear, branched, or ringed molecules |
list the 2 functional groups and classes of organic compounds | 1. carboxyl (R-C=0
-OH)
2. amino
H
(R-C-NH2)
H |
C or H is present but not both | inorganic |
C and H are both present | organic |
plants and algae use _______ carbon as nutrient | inorganic |
E. coli and human use _______ carbon as nutrient | organic |
List 3 types of inorganic molecules | 1. carbon dioxide (CO2)
2. bicarbonate (NaHCO3)
3. carbon monoxide (CO) |
List 3 types of organic molecules | 1. Methane: CH4
2. Glucose: C6H1206
3. Acetic acid C2H402
-Lipids, proteins, sugars, DNA, etc. |
Carbohydrates def. | -also called sugars, general formula (CH20)n
-monosacharides, disaccharides, and polymers |
Carbohydrates function | 1. structural protection (cell wall capsule)
2. nutrient and intracellular energy reserve (such as glycogen)
3. add complexity to protein molecules |
disaccharides | -2 common sugars
-lactose (milk) and sucrose (food) |
What are the major monosaccharides in the cell? | glucose, glactose, and fructose |
lipids are the only macromolecules that don't acquire connect through ___________ | covalent bonds |
several sugars bounded together are called what? | polysaccharides |
sugars are bounded by_________ and process | -glycosidic bonds
-water is released (dehydration)after the bond is formed |
-composed of glucose subunits (α-1, 4 bonding); major form of energy reserve in many plants | starch |
major component of plant cell wall, composed of >2000 glucose subunits (B-1, 4 bonding)
-key component of plant/ very sturdy/ protects the cell | cellulose |
-slimy layer
-white blood cell is too slippery for them to grab onto them
-thats why if found on pathogens it can infect, lungs, brain, etc. | capsule |
Because of its ability to form big polymers _________ are often found in the protective structures of bacterial cells-cell wall and capsule/slime layer | carbohydrates |
lipids define and function | -fats, not soluble in water
Ex of Functions in cells: 1.Triglycerides:storage lipids
2.phospholipids: forms cell membranes that are impermeable barriers
3.sterols such as cholesterol: increase fluids of membrane |
lipids in water will cause what and why? | -cause lipids to aggregate because of the hydrophobic portion it repels water |
Each of the lipid molecules will have a very ______________ | long chain, the longer it is the more hydrophobic it is (8 to 16/18) |
Triglycerides function | storage of lipids in the cell (Ex: fats and oils) |
phospholipids (function) | forms cell membranes that are impermeable barriers |
What are phospholipids an example of? | amphipathetic molecules
-negatively charged (hydrophilic head)
-2 hydrophobic tails
-an ideal barrier material |
sterols | -such as cholesterol: increase fluidity of membrane |
triglyceride define it | 3 hydrophic chain tails causes alchol synthetic is glyceride |
What serves as a major structural component of cell membranes? | -phopholipids |
How is a lipid molecule formed? | -between an alcohol (OH) and a fatty acid (-COOH) via the ester bond
R1-OH+R2-COOH>R1-O-CO-R2+H20
(alcohol)(fatty acid) |
What are associated with cell membranes of eucaryotic cells and bind to the fatty acid of a lipid? | cholesterol |
What is the function of cholesterol? | 1.if breaks up the close packing of the phospholipid tails and makes the membrane more fluid
2. increase membrane stability
3. found in eukaryotes bacteria don't have cholesterol |
no phopholipid group cuases what to happen in a cell? | -cell destroys |
What is the most important macromolecule? | -proteins |
What is protein's function? | -shapers of life, perform most of the activites in a cell
-(enzyme, transport apparatus, structural support, etc.) |
building units of proteins | amino acids (20 types) |
polymer of proteins | -peptide, polypeptide, protein
-each amino acid is linked to another amino acid by a peptide bond |
protein structure | -primary structure, secondary structure, tertinary structure to form unique shape, essential for its biological function
-hydrogen bonds are involved in secondary and tertiary structure |
proteins are most closely related to ___________ because of the long chains | -carbohydrates |
amino acids | -all have an amino group (-NH2) and a carboxyl group (-COOH)
-20 of these vary based on their side groups (R) present
H
NH2-C-COOH
R |
_______forms between the amino group on one amino acid and the carboxyl group on another amino acid | -peptide bond |
a peptide (protein) is an ________________ | -ordered sequence of amino acids |
a peptide is synthesized from the ________ to _____________ | N-terminus to the C-terminus |
different proteins have different _________ | amino acid sequences |
the amino acid sequence is called the _________ of the ________ | -primary structure
-protein |
Secondary structure | -in a peptide, amino acid residues can interact with each other and form helix or pleated sheet
-hydrogen bonds are involved in this structure |
peptide bond is a polymer of 1.________ are synthezied on 2.__________ | 1. amino acids
2. ribosomes |
tertiary structure | -proteins can further fold into 3-dimensional structures and take on a variety of shapes
-hydrogen bonds are also involved in this structure |
shape of protein | -the unique "shape" of the protein enables specific interactions with other molecules allowing it to function
-therefore, hydrogen bonds are crucial in protein function |
nucleic acids | -2 types: deoxyribonucleic (DNA)- double helix structure of a DNA moleucle can form super coils and ribonucleic (RNA)-single stranded often contain secondary structure within |
What is a nucleotide composed of? | 1. nitrogen base
2. pentose
3. phophate |
many virus don't have | DNA |
DNA and RNA are polymers of individual ____________ | nucleotides > building blocks |
nitrogen base | purines: Adenine (A) and Guanine (G)
pyrimidines: Thymine(T) and Cytosine(C)-DNA and Uracil(U)-RNA
T-A
C-G |
pentose sugar | DNA-deoxyribose
RNA-ribose |
Cell fundamental characteristics | 1.reproductions
2.metabolism
3.motility (response to molecules)
4.protection and storage (cell wall or membrane)
5.nutrient transport
3.motility(response to molecules |
Is a virus a cell? | It may contain proteins, nucleic acids, lipids, etc. but it is not a cell |
Virus characteristics | -can reproduce but it needs to go to the host cell and do it for them
-virus has no metabolic reaction
-tumble/stumble random activity once recognizes host cell grabs on
-no storage
-protein protects genetic material |
All of the 4 macromolecules (EXCEPT__________) are formed by polymerization, where subunits, called_____, are bound into chains called__________ | 1. lipids
2. monomers
3. polymers |
Similarity of DNA and RNA | -each strand is formed by an ordered sequence of nucleotides
-neighboring nucleotides are connected by the phosphodiester bonds (between the phosphate and the pentose) |
describe hydrogen bonds in water | -hydrogen bonds can form between water molecules
-attraction between the more positive H atom and a more negative O atom |
What is it called when molecules have both hydrophilic and hydrophopic properties | amphipathic
-such as detergent molecules and phospholipids molecules in cell membrane |
List 5 characteristics of hydrogen bonds (1-3) | 1.are weak bonds: longer distance between the two atoms than covalent and ionic bond2.are easily affected by heat, salt, and pH 3.can occur within one single large molecule (such as a protein) or between two molecules (such as water and solutes) 4 and 5 |
List 5 characteristic of hydrogen bonds (4-5) | 4. numerous in biochemical molecules
5. important for biomolecule function |
difference between DNA vs. RNA | Find Card in mix (chp2) |
What are the 4 major macromolecules? | 1.Carbohydrates
2.Lipids
3.Proteins
4.Nucleic acids |
In lipids the fatty acid portion (-R2) usually has a _________ and is responsible for __________ | 1. long hydrocarbon chains
2. poor solubility of fat |
_________serves as a template for the synthesis of new DNA, mRNA, tRNA, and rRNA | DNA |
most biological activities occur in _______ solutions | aqueous (water based) |
lipids are not_______ but can aggregate through the ________ to from________ | 1. polymers
2. hydrophobic
3. macrostructures |
What is it called when molecules repel water such as fat? | hydrophobic |