Unit 1: Chemistry of Life
What are the significant characteristics of glucose?
Aldehyde group (C branching to bond with hydrogen and double bond with oxygen), 6 carbons,
What is the monomer of a carbohydrate? Identify the components of the monomer.
Saccharides- monosaccharides- chains or rings most often 5-6C
What are the functional groups found in all amino acids?
The functional groups found in all amino acids are the amino (NH2) and carboxyl (COOH-) as well as an R group
Using the properties of water, describe how a water strider can walk on water.
Due to hydrogen bonds allowing water to exhibit cohesive behavior, water has high surface tension. Surface tension measures how difficult it is to stretch/break the surface of a liquid. Because eater has a high surface tension, it allows a water strider to walk on it without breaking
what type of molecule is a water molecule?
Polar covalent
What is denaturation?
a structural change in a protein that results in a loss of its biological properties
What is hydrolysis reaction?
add a water molecule to cleave the covalent bond between two monomers in a polymer
What are the elements found in a lipid?
carbon, hydrogen, oxygen (sometimes sulfur, phosphorus, nitrogen)
What are the elements found in a protein?
carbon, hydrogen, oxygen, nitrogen (most contain sulfur)
What is dehydration synthesis?
join two monomers together into a polymer and a water molecule is removed.
What is a hydrogen bond?
noncovalent attraction between a hydrogen atom bonded to an electronegative atom (O,N,F) and another electronegative atom; usually nitrogen or oxygen (maybe fluorine)
look at doc for hydrophobic/hydrophilic/charged practice
ok
Do pyrimidines have one or two rings?
one
What is at the 5' end of DNA?
phosphate group
What are parts found in all nucleotides?
phosphate group bonded to a five carbon sugar bonded to nitrogenous base
How does hydrogen-bonding allow for water's versatility as a solvent?
Because water is a polar molecule it has partially positive and partially negative parts. These partially charged parts of water molecules can bond to, separate, and isolate the partially positive and partially negative parts of the solute.
What are the elements found in a carbohydrate?
Carbon, Hydrogen, Oxygen
What leads to denaturation?
Temperature, pH, salinity changes
How does hydrogen-bonding allow for the cohesive behavior of water?
The cohesive behavior of water occurs within water as hydrogen bonds between neighboring water molecules keep the substance together
What are the components of a fat molecule?
Three fatty acids + glycerol
What are the components of a phospholipid?
Two fatty acids + glycerol + phosphate group
How does hydrogen-bonding allow for the ability of water to moderate temperature?
Water has a high specific heat due to hydrogen bonds as energy (heat) is required to break the bonds between water molecules before speeding up water molecules and increasing temperature
Describe why water is considered a polar molecule.
Water is considered a polar molecule because its overall charge is unevenly distributed. Therefore, the oxygen region is partially negative and each hydrogen is partially positive. The polarity of this molecule is also indicative of its bent shape.
What is at the 3' end of DNA?
hydroxyl group
What are the four macromolecules?
Carbohydrates- include sugars and polymers of sugars (monosaccharides, polysaccharids, etc.) Lipids- fats, steroids Proteins- enzymes (transport proteins etc.) Nucleic Acids- DNA, RNA
What are the elements found in nucleic acids?
Carbon, Hydrogen, Oxygen, Nitrogen, Phosphorus
What are the significant characteristics of fatty acids?
Carboxylic acid group on end (C double bonded to Oxygen and single bonded to OH), the rest is hydrogen and carbon
What are the significant characteristics of glycerol?
3 carbons, hydroxyl group, no aldehyde
Using the properties of water, describe how water can move up a capillary tube to move from the roots to the leaves in a plant.
As water evaporates from the leaf, hydrogen bonds cause the water molecules leaving the veins to tug on the molecules further down- pulling the water up through the plant. This is made possible by cohesion as the water attempts to stick together, and also adhesion as adhesion of water to cell walls by hydrogen bonds helps counter the downward pull of gravity as water moves up the capillary tube.
How does hydrogen-bonding allow for water to expand upon freezing?
At temperature at 4ºC and higher, water behaves like any other liquid. From temperatures at 4ºC to 0ºC water molecules begin to move too slow to break the hydrogen bonds between water molecules and it forms ice. Because the hydrogen bonds keep other water molecules "arms-length" apart, this forms a crystalline lattice, enabling ice to be 10% lighter than water. This is why ice floats above the water, preserving aquatic life below it.
What is the structure of an amino acid?
At the center of the amino acid is a carbon atom called alpha carbon. Bonded to it is an amino group, carboxyl group, hydrogen atom, and a variable (R) group- a.k.a side chain- which determines the unique characteristics of the amino acid.
Where are hydrogen bonds found in DNA?
Hydrogen bonds are responsible for specific base-pair formation in the DNA double helix. They are also integral to the stability of the structure.
How many hydrogen bonds are found between complementary base pairing?
Between adenine and thymine there are two; there are three between guanine and cytosine.
Describe the structure of a steroid.
Four fused carbon rings (the last looks like a dog house)
Where are hydrogen bonds found in water?
Hydrogen bonds are found between a hydrogen atom of one water molecule and an oxygen atom of another. One water molecule can form 4 hydrogen bonds at one time.
What are three functions of proteins in living organisms?
Nearly every dynamic function of a living being depends on proteins 1) Enzymes- Catalyze chemical reactions in body (digestive enzymes catalyze hydrolysis of bonds in food molecules) 2) Transport proteins - Transports substances across phospholipid bilayer 3) Contractile and motor proteins - movement such as contractions of muscle (for all see page 58)
What are the three options for the R group? For each R group option, describe the polarity and justify your reasoning.
Nonpolar R groups are hydrophobic and typically have a nonpolar bond of Carbon - Hydrogen. Polar R groups are hydrophilic and are identified by a bond of oxygen to hydrogen or sulfur to hydrogen. Finally, electrically charged R groups are hydrophilic and possess a carboxyl - carbon double bonded to oxygen making it acidic (-) - or amino (NH2/3) making it basic (+)
What is the monomer of a nucleic acid? Identify the components of the monomer.
Nucleotides
What are three functions of carbohydrates in living organisms?
Remember- Storage/Structure Plants store starch- a polymer of glucose monomers. Synthesizing starch allows them to stockpile glucose and glucose=energy Animals store glycogen in mainly liver and muscle cells. Breakdown of glycogen in these cells release glucose when the demand for energy increases Cellulose is a major component of the tough walls that enclose plant cells (alternating orientation of glucose molecules provides stability compared to starch) Chitin is used by arthropods to build their exoskeleton. Fungi also use it to build their cell wall. (similar to cellulose except glucose monomer has N-containing attachments)
What is evaporative cooling?
The highest energy molecules will evaporate first, cooling the surface of remaining liquid
What are three properties of water?
There are four properties of water: cohesive behavior, ability to moderate temperature, expansion upon freezing, and versatility as a solvent.
What are three functions of nucleic acids in living organisms?
There are two types of nucleic acid: Deoxyribonucleic acid- genetic code- all necessary to build organism Ribonucleic acid- essential for coding, decoding, regulating/expressing genes Storage and transmit hereditary and genetic information
