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What are lipids?
nonpolar hydrocarbons that are insoluble in water
how many electrons are shared between 2 atoms in a triple bond?
3 - 3 lines
What is an atomic number?
number of protons in an atom
What is all matter composed of?
atoms!!!
What determines the sequence of amino acids?
gene instructions
What are the 2 shapes that form in a secondary structure? what bonds make them?
a helixes and b pleated sheets. made by hydrogen bonds
what is the general formula for a carbohydrate?
(CH2O)n n>3
What is the difference between a disaccharide and an oligosaccharide? What bond forms them?
Disaccharides: 2 simple sugars
Oligosaccharides: 3-20 monosaccharides
covalent bonds!!
What varies in isotopes?
the number of neutrons
What level of organization are electrons at?
subatomic
How do proteins become denatured, in terms of environment and bonds?
When cells are exposed to undesirable environments, weak bonds can break, causing loss of protein folding (denatured)
what orbitals do electrons fill first?
orbitals closest to the nucleus
What is the structure of a triacylglyceride?
3 fatty acids and a glycerol backbone
how are polysaccharides built?
monosaccharides undergo a dehydration reaction, forming a covalent bond and releasing water
What 2 bonds are weak and most likely to break via denaturation?
hydrogen and ionic
Suppose an atom loses 2 electrons. What kind of ion would it become (anion v cation)? What would the charge be? explain in terms of charges.
The atom would become a cation (+), because it is losing 2 electrons, which are negatively charged.
The charge would be +2
in which type(s) of bonds are electrons transferred, shared, or not shared?
covalent: shared
ionic: transferred
hydrogen: not shared
partially positive Hydrogen + partially negative Oxygen, both formed from a peptide bond.
What protein structure is least likely to break via denaturation? why?
primary because all of the bonds are covalent
What environmental variables can cause denaturation? What are the ranges that proteins like to stay in?
temperature - small temp range (too hot = denaturation)
pH - narrow pH range (too basic or acidic = denaturation)
Suppose there are 2 molecules:
C10H22 vs C6H12O6
Which is hydrophobic? which is hydrophilic? which is polar? which is nonpolar?
explain your reasoning in terms of electronegativity, chemical structure, and chemical bonds present and what atoms they are between.
C10H22 is nonpolar and hydrophobic. it is a long hydrocarbon chain with nonpolar covalent bonds between H and C, which you can determine from an electronegativity chart. Because there is no electronegativity difference, these are nonpolar and therefore hydrophobic.
C6H12O6 is polar and hydrophilic. Its does have carbon and hydrogen, but it also contains polar covalent bonds between carbon and oxygen, due to the differences in electronegativity. This EN difference makes the bonds polar, and therefore the molecule is hydrophilic and polar.
What are the bonds found in primary, secondary, and tertiary structures?
primary: peptide bond (covalent)
secondary: Hydrogen bond (attraction)
Tertiary: covalent, hydrogen, and/or ionic
What are the electronegativity differences for polar covalent, nonpolar covalent, and ionic bonds?
How would you figure this out when given a chart?
PC: 0.5 - 1.9
NPC: 0 - 0.4
IB: >1.9
subtract the value of one atom from another and see what the difference is
What are the 3 important polysaccharides? what do they do and what are their structures?
Starch - storage of glucose in plants - branched because the OH beads are on the same side
Glycogen - storage of glucose in animals - branched because OH are on the same side
Cellulose - main structural component of plant cell walls, also a glucose polysaccharide - linear structure because of the position of OH (opposite)
In a straight chain 4 carbon molecule, how many hydrogens are present?
bonus: come up to the board and draw the structure, label the carbons and hydrogens.
10!