week 1 additional flashcards from quiz and tut
Glucose and galactose are ……
structural isomers
Which of the following statements about carbon are true?
-It can form covalent bonds
-It forms the framework of biological molecules.
Long polymers made of monosaccharides that have been linked through dehydration reactions are called ….
polysaccharides
C-C and C-H bonds are….
non-polar
C-N AND C-O bonds are …
polar, as electrons in the covalent bond spend more time close to the nitrogen or oxygen atom.
Nonpolar covalent bonds involves
an equal sharing of one or more pairs of electrons.
polar covalent bonds are formed by…
an unequal sharing of one or more electron pairs.
Oxygen is more …. than carbon
electronegative as it is in a higher periodic table group.
glucose and fructose are
structural isomers
Select which ones are polysaccharides:
cellulose, cholesterol, starch, chitlin, fructose, glycogen
cellulose, starch, chitlin, glycogen.
which of the following bonds is essentially non-polar?
C-H
What are the monomers of nucleic acids?
Nucleotides
Glucose and galactose are…
stereoisomers
Carbon-oxygen and carbon-nitrogen bonds are described as which of the following?
Nonpolar covalent
Formed by an equal sharing of electrons
Formed by an unequal sharing of electrons
lonic OR
Polar covalent
Formed by an unequal sharing of electrons, AND POLAR COVALENT
Identify functions of ATP
To power transport across cell membranes
To drive energetically unfavourable reactions
To power the movement of cells
Which of the following are functions of proteins?
-They transport ions and molecules across cell membranes.
-They provide structural support for many animal tissues.
-They play a key role in the contraction of muscles.
* They are the main component of plant cell walls.
-They are the most efficient molecules for storing energy.
* They catalyze chemical reactions.
They transport lons and molecules across cell membranes.
They provide structural support for many animal tissues.
They play a key role in the contraction of muscles.
They catalyze chemical reactions.
What type of bonds are responsible for the base pairing between two strands of DNA in the double helix?
HYDROGEN
The two major functional groups found in all amino acids are the basic …. group and the acidic …..
amino
carboxyl
what are the the functions of proteins in living cells
They play a key role in moving materials within cells.
They catalyze chemical reactions.
They help the body recognize and destroy foreign microbes and cancer cells.
They transport oxygen in the blood of vertebrates,
Where are the sugar-phosphate backbones and the nitrogenous bases located in the DNA double helix?
The sugar-phosphate backbones run along the outside of the double helix while the nitrogenous bases pair in the middle.
Proteins are polymers made up of how many different amino acids?
20
What are the three major structural components of an amino acid?
Amino group
Side chain (R)
Carboxyl group
The 20 common amino acid are classified into five chemical classes based on which of the following?
Their R groups
What are the two major functional groups found in an amino acid, which allow it to form a peptide bond with another amino acid?
Carboxyl group
Amino group
Match the following special amino acid to their unique functions in proteins:
Methionine
Proline
Cysteine
Causes kinks in the chain
Links two chains together
Often the first amino acid
Methionine:Often the first amino acid
Proline: Causes kinks in the chain
Cysteine:Links two chains together
Which of the following accurately describes the chemical structure of a typical amino acid found in a protein?
A central carbon atom is bound to an amino group, carboxyl group, a side chain, and a hydrogen atom.
The peptide bond:
-is a unique double bond that allows partial rotation -is a single bond that can be fully rotated
-has a partial
double-bond character that prohibits rotation
has a partial
double-bond character that prohibits rotation
Match amino acids to the group they belong to (base on their R group).
Threonine
leucine
glutamic acid
phenylalanine
charged
nonpolar
aromatic
polar uncharged
Threonine:polar uncharged
leucine:nonpolar
glutamic acid: charged
phenylalanine: aromatic
The covalent bond that joins 2 amino acids is called a(n) ….. bond.
peptide
Where are non-polar and polar amino acids found in a folded protein?
non-polar: interior
polar: exterior
4 hierarchial levels of protein structure=
primary, secondary, tertiary, and quaternary
Select amino acids that are most likely to be found in the interior of a protein:
Phenylalanine
Leucine
Lysine
Glutamic acid
Valine
Phenvialanine
Leucine
Valine
What is the primary structure of a polypeptide?
The amino acid sequence of the polypeptide,
Which type of interaction plays a key role in determining both the secondary and tertiary structure of a protein?
Hydrogen bonds
Regarding polypeptides, the 2 basic types of …. structures are alpha …. and beta-pleated sheet.
secondary
helix
How many polypeptides are present in a protein whose highest level of structure is tertiary structure?
1 polypeptide only
Which of the following is important for the function of chaperonins as they refold misfolded proteins?
-They can hydrolyze ATP to power the changes in protein structure.
-They can force many simultaneous changes in the structure of a misfolded protein, causing it to refold quickly in a single step.
-They have a very flexible structure.
-They are very rigid and this rigidity allows them to force misfolded proteins into the correct tertiary structure.
-They can hydrolyze ATP to power the changes n protein structure
-They have a very flexible structure.
What are the two basic types of secondary structure in proteins?
a- helix and -pleated sheet
Match the level of protein organization with the proper description.
-Primary
-Secondary
-Tertiary
-Quaternary
-the overall 3d shape of each polypeptide
-how 2 or more polypeptides interact to form a protein
-the linear sequence of amino acids
-repetitive folding patterns such as aplha helix and beta pleated sheet
Primary:the linear sequence of amino acids
Secondary: repetitive folding patterns such as alpha helix and beta pleated sheet
Tertiary:the overall 3d shape of each polypeptide
Quaternary:how 2 or more polypeptides interact to form a protein
Diseases caused by the improper folding of proteins may be due to deficiencies in …. proteins.
chaperone
Which of the following best describes the relationship between temperature and enzyme activity?
-Changes in temperature have little effect on enzyme activity, as long the the temperatures are not too extreme.
-Each enzyme has an optimum temperature where it functions best.
-As temperature increases, enzyme activity always decreases.
-As temperature increases, enzyme activity always increases.
Each enzyme has an optimum temperature where it functions best.
Select the disease type that could result from a deficiency in chaperone proteins.
a disease caused by improper folding of proteins
The main chemical characteristic that lipids share is that they are… in water
insoluble
Hydrogen bonds between the amino and carboxyl groups of the polypeptide backbone help determine protein ….. structure while hydrogen bonds between the amino acid side chains help determine protein …. structure.
secondary
tertiary
a ……..consists of a long-chain hydrocarbon with a carboxyl group attached at one end.
fatty acid
Which of the following is an accurate description of a triglyceride?
-Three glycerol molecules joined to one fatty acid
- A three-carbon chain where each carbon is bound to a hydroxyl group
-One glycerol molecule joined to three fatty acids
-A hydrocarbon chain bound to 3 carboxyl groups
One glycerol molecule joined to three fatty acids
A fatty acid that has double bonds between one or more pairs of successive carbon atoms is said to be
unsaturated
Choose all of the following that accurately describe oils, such as olive oil?
-Oils have high melting points and are solid at room temperature.
-Oils are fats that are high in unsaturated fatty acids.
-Oils are fats that are high in saturated fatty acids.
-Oils have low melting points and are liquid at room temperature.
-Oils are fats that are high in unsaturated fatty acids.
-Oils have low melting points and are liquid at room temperature.
Fats containing polyunsaturated fatty acids have … melting points.
lower
Many lipids are composed of two main kinds of molecules ….. acids and 3-carbon polyalcohol …..
fatty
glycerol
triglycerides or triacylglycerols are also known as….
fats
How do saturated and unsaturated fats differ in their ability to pack together?
Unsaturated fats cannot pack as tightly as saturated fats because of the presence of double bonds between the carbon atoms.
The presence of polar ……
bonds between some of the carbon atoms in the hydrocarbon chains of a fat influences whether it is a solid or liquid at room temperature.
double
From the following list, choose all lipids.
Polypeptides
Oils
DNA and RNA
Terpenes
Fats
oils, terpenes, fats
Match the type of fatty acid with the correct description.
-Saturated fatty acids
-Polyunsaturated fatty acids
-Monounsaturated fatty acids
-Two or more double bonds between carbon atoms
-One double bond between carbon atoms
-No double bonds between carbon atoms
Saturated fatty acids:No double bonds between carbon atoms
Polyunsaturated fatty acids:Two or more double bonds between carbon atoms
Monounsaturated fatty acids: One double bond between carbon atoms
Why are fats and oils more efficient in storing energy than carbohydrates or proteins?
They have a higher ratio of energy storing C-H bonds.
The structure of a phospholipid can best be described as which of the following?
-Glycerol Joined to 2 fatty acids and a phosphate group
-Glycerol joined to 3 fatty acids and a phosphate group
-A 5-carbon sugar joined to a nitrogenous base and a phosphate group
- A 5-carbon sugar joined to a nitrogenous base and 2 phosphate groups
-Five interlocking carbon rings joined to a phosphate group
Glycerol joined to 2 fatty acids and a phosphate group
In general, which of the following is an accurate description of the chemical structure of fatty acids?
-A hydrocarbon chain with a terminal carboxyl group
-Three hydrocarbon chains bound to each of the three carbons of a glycerol molecule
-A three carbon chain where each carbon is bound to a hydroxyl group
-A hydrocarbon chain with a terminal carboxyl group
Which of the following are lipids?
-Starch and glycogen
-Fats
-Steroids
-nucleotides
-Fats
-Steroids
Which group of biomolecules is the most efficient for storing energy?
-Nucleic acids
-Monosaccharides
-Polysaccharides
-Fats and oils
-Proteins
Fats and oils
Which of the following subunits are found in all phospholipids?
-5-carbon sugar
-Glycerol
-Fatty acids
-Phosphate group
-Nitrogenous base
-Amino group
Glycerol
Fatty acids
Phosphate group
What are some properties of water molecules that are important in biology?
1.Water is polar.
2.Water forms (weak) Hydrogen bonds.
3.Water has adhesive and cohesive properties
4.Water has a high specific heat capacity, and a high heat of vaporization.
How is water polar and solvent ?
The Oxygen in H2O is slightly electronegative, whereas each Hydrogen atom has a partial positive charge. This allows water to interact with other polar molecules, and often allows it to break bonds in other molecules. Breaking bonds in those other molecules makes water a solvent, and it’s really good at dissolving stuff.
why is water being polar important to biology?
water is a solvent, and it’s really good at dissolving stuff. This is important because it allows water to transport solutes and biological molecules.
How/why does water form weak hydrogen bonds?
Water forms (weak) Hydrogen bonds. (This is why when water freezes, it expands.) Liquid H2O molecules (water) bounce around pretty freely and form transient H-bonds, but in their solid state, H2O molecules form a rigid crystal lattice (I picture this like a chain-link fence, where each intersection is a molecule and each bar is a Hydrogen bond). The bonds in the crystal lattice are father apart than the brief H-bonds in water, which makes ice less dense than water.
why is water forming H bonds important to biology?
This is super important because it allows the top layers of many bodies of water to freeze, without freezing the water all the way through. This insulates the water below, and allows for life to thrive under the ice. It also allows my grandpa to go ice fishing in the winter.
How/why does water have adhesive and cohesive properties
due to H2O being a polar molecule. Adhesion = water wants to stick to other surfaces, and Cohesion = water wants to stick to itself. First, water adheres to the inside surface of the root (think of it creeping up the edges, like inside a straw). Then, since water is cohesive and wants to stick to itself, it kind of brings itself up in attempt to be level.
Why is water being adhesive and cohesive important to biology?
Together, they allow for water to travel up plant stems (in the xylem).
How/why does Water has a high specific heat capacity, and a high heat of vaporization.
Because of its Hydrogen bonding, it’s really hard to change the temperature of water (depending on how much water there is), and it’s hard to heat water up. It also takes a lot of heat release to cool water down.
Why is water being a high specific heat capacity, and a high heat of vaporization important to biology?
This makes water really good at moderating temperatures, which is really important for climate. It’s why regions near the ocean usually have moderate temperatures within a pretty narrow window. Generally, water keeps temperatures in a window that allows for life on Earth.
what is Bond notation
– Single covalent bonds are written as H-H.
– Double covalent bonds are written as O=O.
what is a covalent bond?
Covalent bond - when two atoms do not have completely full outer shells, they may share electrons so that each has a full outer shell
what are nonpolar and polar covalent bonds
Nonpolar covalent bond – equal sharing of electrons between atoms
* Polar covalent bond – unequal sharing of electrons
what is electronegativity and example?
Electronega2vity – the atraction of an atom for the electrons in a covalent bond
– In H2O, the larger oxygen atom is more electronega<ve than the hydrogen atoms.
* O atom is slightly nega<ve (δ–, “delta minus”)
* H atoms are slightly posi<ve (δ+, “delta plus”)
Water is an excellent solvent for ….
polar/charges molecules e.g. salt (NaCI, sugars etc). The slight negative charge on water attracts positive charges (Na).
The slight positive charge on water attracts negative charges (Cl).
