Molecules of Life Flashcards
List the components of an atom
nucleus, protons, electrons and neutrons
List the types of chemical bonds
- Covalent
- hydrogen bonds
- Ionic Bonds
- (vander walls interactions)
Define a covalent bond
A covalent bond is the sharing of a pair of valence electrons by two atoms
What elements make up 97% of life?
Carbon, Hydrogen, NItrogen, Oxygen, Phosphorus and sulfer
Why is water polar (think electronegativity and asymmetry of water molecule)
Hydrogen has less electronegativity therefore oxygen pulls electrons more. That means the oxygen side is slightly more negative and the 2 hydrogen side is more positive
Are these bonds polar or non polar C-H c double bond c o-h c-o n-h
C-H= non polar c double bond c=non polar o-h=polar c-o= polar n-h= polar
Rank these from most electronegative to least
Oxygen, carbon, hydrogen and nitrogen
1) OXYGEN
2) NITROGEN
3) CARBON
4) HYDROGEN
When do hydrogen bonds form
WHEN TWO DIFF MOLECULES THAT HAVE A HYDROGEN AND ARE DIPoles CAN HAVE A HYDROGEN BOND
They form when the partial positive charge of hydrogen atoms are attracted to the partial neg charge of oxygen atoms
Name the properties of water and describe them
1) Water is cohesive
(hydrogen bonds create surface resistance think of going through just straight marbles vs going through the marbles attached with toothpicks, where hydrogen is the toothpick)
2) Water moderates temperature changes(ie. costal regions are cooler than inner cities)
This happens because water in the ocean gets “too hot: therefor must break hydrogen bonds to evaporate but in order to do that must absorb heat from environment while the remaining molecules are “cooler”
3)ice is less dense than water
(Ice is less dense than water because the orientation of hydrogen bonds causes molecules to push farther apart, which lowers the density.)
4) Water adheres to hydrophilic surfaces
(example: anything that dissolves in water)
What is the difference between hydrophobic and hydrophilic
1.Hydrophilic means water loving; hydrophobic means resistant to water.
2.Hydrophilic molecules get absorbed or dissolved in water, while hydrophobic molecules only dissolve in oil-based substances.
4.Hydrophilic molecules are polar and ionic;
hydrophobic molecules are non-polar.
Inorganic compound vs organic compound
the presence of a carbon atom; organic compounds will contain a carbon atom
Why is carbon so versatile?
It can form 4 covalent bonds therefore many different combinations of things can be made… Carbon makes isomers
Define an isomer
Something that has the same chemical formula but a different structure.
What is the process of going from monomer to polymer called and explain
Dehydration/ condensation
It means to remove a water molecule and form a new bond
What is the process of going from polymer to monomer called and explain
Hydrolysis
It means to add a water molecule which breaks the original bond
List the 4 biomolecules
1) Carbohydrates
2) Nucleic Acids
3) Proteins
4) Lipids
Give 3 examples of a carb monomers.. these are also called what>
galactose,
glucose
fructose
CALLED MONOSACCHARIDE ISOMERS
What are the two roles of carbs
Fuel and Structure
What is the difference between alpha glucose and beta glucose
2) which is better for fuel, which is better for structure
Alpha: OH is down (fuel/energy)
Beta: OH is (structure)
Ratio of carbs
Cn (H2n) On (1:2:1)
What are the two shapes of carbs? Which is more common?
Linear and Cyclic
Cyclic is more stable therefore is 97%
Why is fructose different from glucose and galactose?
It has a 5 member ring, not 6
What is the bond called between two carbon monomers?
GLYCOSIDIC BONDS
What process do monomers go through to become polymers?
Dehydration/condensation
Name two carb disaccharides and from which monosaccharides are they formed from?
Glucose+Glucose=Maltose
Glucose+Fructose=Sucrose
Name two starch polysaccharides and the difference between the two
Amylopectin (branches) and Amylose (no branches)
What are the 4 main polysaccharides of carbs
- Glycogen
- Starch
- Cellulose
- Chitin
What is glycogen and know the structure
Animal storage of sugar
Linked, branched glucose
α1-4 and α1-6 glycosidic links
What is starch, what are the two most popular plant starches, and know the structure and functions
Plant storage of sugar Amylopectin Branched glucose ~70% of starch α1-4 and α1-6 glycosidic links Intermediate term storage
Amylose Unbranched glucose More dense α1-4 glycosidic links Long term storage
Which is better for long tern storage and why?
Amylopectin or Amylose
Amylose: because it is unbranched therefore harder to break down
What is cellulose for? what is the shape>
FOr structure
with a straight shape due to beta 1-4 linkages
What is chitin and where is it found
it is a derivative of glucose and it in found in cell wall of fungi, exoskeleton of anthropoids and even used in surgical thread
What is the role of nucleic acids
Carriers of genetic info (DNA AND RNA)
What is the monomer of nucleic acids?
Nucleotides
what is a nucleotide made of?
1) Pentose (5 carbon sugar)
in dna it is deoxyribose, in rna is is ribose
2) phosphate group (attached to the carbon 5 of the pentose)
3) nitrogenous base
What are the pyrimidines what are the purines
PURINES: adenine, guanine.
PYRIMIDINES: thymine, uracil, cytosine
What is the form of DNA
DOUBLE HELIX
how are the two dna strands bonded?
Hydrogen bonds
Characteristic of DNA
Deoxyribonucleic acid Nucleotides missing a hydroxyl group on the sugar Double-stranded More stable In the nucleus forever Longer (millions of nucleotides) A,T,G,C T = Thymine!
Characteristics of RNA
Ribonucleic acid Single-stranded Exported from the nucleus Shorter A,U,G,C U = Uracil!
How are nucleotides connected?
Phosphodiester Bonds linking 3 carbon to 5 carbon
How are nitrogenous bases connected?
Hydrogen Bonds
What pairs with Adenine
What pairs with Guanine
with adenine (Thymine in dna, uracil in RNA) With guanine (cytosine)
What are the monomers of protein?
Amino acids
What are the components of an amino acid?
Amino group
Carboxyl group
R group (gives its identity) reactive group
What are the 8 types of proteins and their functions
1) Structural=for support
2) Storage=to store amino acids
3) transport= to transport substances
4) Hormonal/signalling=coordination of organisms activities
5) Defensive= protect against disease
6) contractile and motor: for movement
7) receptor: response of cell to chemical stimuli
8) enzymatic: selective acceleration of chemical reactions
example of structural protein
Keratin, silk, collagen, elastin
example of storage protein
casein (in milk), ovalbumin
example of transport protein
hemoglobin
example of hormonal protein
insulin
example of defensive protein
antibodies (white blood cells)
example of contractile protein
actin and myosin
example of enzymatic protein
digestive proteins to break bonds in food
example of receptor protein
proteins within the membrane of a nerve cell
How many kinds of amino acids?
20 kinds
By what bonds are amino acids linked by? and what process?
Peptide bonds!! (between the N of the amino group and R of the carboxyl group)
Done by condensation/Dehydration
What gives.a protein its shape and its specific role?
The combination/sequence of amino acids
WHAT is the structure of a protein
SEE SLIDE NOTES
what are the difference characteristics of the r groups
- hydrophobic
- hydrophilic
- charged
- acidic/basic
can amino acids by amphipathic?
YES
What are the 4 levels of structure in proteins
1) Primary (really zoomed in)
2) secondary
3) tertiary
4) quaternary (really zoomed out)
Explain the primary level of proteins
Unique Amino acid sequence (adjacent amino acids) of 1 protein
determined by inherited info
explain the secondary level of proteins
Interactions between non-adjacent amino acids of 1 protein
These interactions make shapes (twists & turns in the protein) held by H bonds
explain the tertiary level of proteins
Interactions between R-groups of 1 protein
Many types of bonds involved
Larger scale shapes
explain the quaternary level of proteins
Interaction between different proteins
When two or more polypeptides (proteins) combine to form a macromolecule
Why is the folding of amino acids important
Improper folding means the protein will not function correctly
Explain denaturation and why it occurs
it is the result of protein unfolding due to extreme conditions like temperature, pH, solvents
What are the 4 families of lipids
- fatty acids
- fats (triglycerides)
- Phospholipids
- Steroids
what is the monomer of lipids
Fatty acids
what do all the different lipid families have in common
They are non-polar (ie. hydrophobic)
What is the ratio of fatty acids
1;2;1 (carbon, hydrogen,oxygen)
What are the components of a fatty acid
1x hydrocarbon chain
carboxylic acid
What is the difference between saturated, monounsaturated and polysaturated
saturated: no double bond
Monosatured: one double bond
poly; several double bonds
what do double bonds cause?
A KINK
What state are unsaturated fats in?
liquid/fluid because they have double bonds
what state are saturated fats in?
Solid/viscous because they have no double bonds (ie. tightly packed)
What are the components of triglycerides
- Glycerol
- 3x fatty acids
What does excessive consumption of saturated fat lead to?
Cardiovascular diseases
What is the role of fatty acids
BUILDING BLOCKS
What is the role of triglycerides?
Serves as storage
Are triglycerides hydrophobic or hydrophilic
HYDROPHOBIC
Where do you find saturated fats? Unsaturated sats?
saturated: butter, animal fat
unsaturated: oils, plants, fish
What are trans fats?
ARTIFICIALLY saturated fats (hydrogenated fats)
Do transfats have a kink?
nope, they are solid at room temp like saturated
What are phospholipids
The building blocks that form the cell membrane (aka phospilipid bilayer)
What are phospholipids made of?
1x glycerol
2x fatty acids
1x phosphate group (neg. charge.
1x variable hydrophilic group
Explain hydrophobic and hydrophilic heads and where to find them in fats
In the phospholipid bilayer, you find the hydrophilic heads on the outside and the hydrophobic tails on the inside
What do phospholipids form in water and explain them
Form micelles/capsules
Why are steroids important?
They prevent fatty acid tails from moving when temp is too high and prevent them from packing when temp is too low
What are steroids made from
4 fused rings
Are steroids hydrophilic, hydrophobic or amphipathic
amphipathic
Give an example of a useful steroid
cholesterol
