AP biology
Lipid monomer
fatty acid
Which of the following is a monomer?
glucose
6C
hexose (glucose)
Alpha helix is held by what type of bond?
hydrogen bond
Explain nucleic acids
- genetic material - stores info - transfers info
Craboxyl
-COOH
Explain carbohydrates
-carbohydrates are sugar molecules used for energy production or storage or a structural components. -the arrangement matters
Explain lipids
-lipids are a major components of membranes -they provide a way to keep your water from mixing with everyone else's water -they have a hydrophobic and hydrophilic part
Explain proteins
-proteins are a sequence of amino acids (amino acids are held together by covalent bonds mainly peptide bonds) -structure is held together by ionic and hydrogen bonds -proteins are susceptible to temperature
how do you create a polymer?
2 monomers = polymer
Hydrolysis
A chemical process that splits a molecule by adding water.
dehydration synthesis
A chemical reaction in which two molecules covalently bond to each other with the removal of a water molecule.
What maintains the secondary structure of a protein?
hydrogen bonds between the amino group of one peptide bond and the carboxyl group of another peptide bond
polar molecules are... (hydrophobic or hydrophilic?)
hydrophilic (like water)
Non-polar
hydrophobic
non-polar molecules are...(hydrophobic or hydrophilic)
hydrophobic (dislike water)
Polymers
large compound formed from combinations of many monomers
Polysaccharides
large macromolecules formed from monosaccharides
Lipid function
long term energy storage
Water molecules are polar covalent molecules. There is a partial negative charge near the oxygen atom and partial positive charges near the hydrogen atoms due to the uneven distribution of electrons between the atoms, which results in the formation of hydrogen bonds between water molecules. The polarity of water molecules contributes to many properties of water that are important for biological processes. Which of the following models best demonstrates the arrangement of hydrogen bonds between adjacent water molecules?
look at picture for answer! Why: Correct. The hydrogen bonds between these water molecules correctly show the attractive force between the hydrogen atom of one water molecule and the oxygen atom of the adjacent water molecule.
Carbohydrates function
main source of energy
Isomers
molecules with the same molecular formula but different structures
Carbohydrate monomer
monosaccharide
quartenery structure
more than one polypeptide chain bonded together
Sugars
most sugar names end in -ose
Nucleic monomer
nucleotide
5C
pentose (ribose)
protein polymer
polypeptide
carbohydrate polymer
polysaccharide
If you change one amino acid what structure/structures does it change
primary, secondary, and tertiary
primary structure
sequence of amino acids
RNA
single helix ribose U-A (2 bonds) C-G (3 Bonds)
monosacchride
single sugar unit in monosacchrides (glucose,fructose,galactose) 2 molecules in disaccarides ( sucrose, lactose, maltose) or multiple molecules in saccharides (starch,dietary fiber, glycogen)
Monomers
small unit that can join together with other small units to form polymers
nucleic acid function
store and transmit genetic information
protein functions
structural support, storage, transport, cellular communications, movement, and defense against foreign substances
Protiens
substances that help build and maintain body cells and tissues
5c and 6c
sugars form rings in solutions
surface tension
the force that acts on the surface of a liquid and that tends to minimize the area of the surface
Lactase is an enzyme composed of a single polypeptide that hydrolyzes the disaccharide lactose to produce monosaccharides. The optimal pH for lactase activity is 6. Transfer of lactase to pH 5 results in a substantial decrease in enzyme activity, likely due to the disruption of
the secondary and tertiary structures of the enzyme.
Carbohydrates
the starches and sugars present in foods
secondary stucture
the structure of a protein molecule resulting from the regular coiling or folding of the chain of amino acids.
3C
triose (glyceraldehyde)
Craboxyl
two oxygen atoms; one double bonded and one single bonded
Pyrimidines
uracil, cytosine, thymine
tertiery structure
whole molecule folding
Properties of water
• strong hydrogen bonds • high specific heat • high boiling point • needs a lot of energy to evaporate • expands when freezes
Disaccharide
A double sugar, consisting of two monosaccharides joined by dehydration synthesis.
Which of the following best describes the process that adds a monosaccharide to an existing polysaccharide?
A specific enzyme removes the hydrogen (HH) from the monosaccharide and the hydroxide (OHOH) from the polysaccharide, creating a bond between the two and creating a water (H2OH2O) molecule. Why: This is a description of dehydration synthesis, which joins multiple monosaccharides to create a polysaccharide and produces water (H2OH2O) molecules.
Macromolecules
A very large organic molecule composed of many smaller molecules
Purines
Adenine and Guanine
Which statement describes how water is pulled up through the xylem to the leaves of the plant?
As water exits the leaf, hydrogen bonding between water molecules pulls more water up from below. Why: As water exits the leaf, hydrogen bonding pulls more water molecules up through the leaf and xylem by cohesion.
Hydrophilic
Attracted to water
Cohesion
Attraction between molecules of the same substance
protiens elements
carbon, hydrogen, oxygen, nitrogen
Nucleic Acids Elements
carbon, hydrogen, oxygen, nitrogen, phosphorus
Why is water polar?
Because it has positive and negative poles.
Figure 1 represents a segment of DNA. Radiation can damage the nucleotides in a DNA molecule. To repair some types of damage, a single nucleotide can be removed from a DNA molecule and replaced with an undamaged nucleotide. Which of the four labeled bonds in Figure 1 could be broken to remove and replace the cytosine nucleotide without affecting the biological information coded in the DNA molecule?
Bonds Y and Z at the same time. Why: By breaking bonds Y and Z at the same time, the cytosine nucleotide could be removed from the DNA molecule and replaced with an undamaged cytosine without changing the biological information stored in the DNA.
Which of the following best describes a structural similarity between the two molecules shown in Figure 1 that is relevant to their function?
Both molecules contain nucleotides that form base pairs with other nucleotides, which allows each molecule to act as a template in the synthesis of other nucleic acid molecules. Why: Nucleotides form base pairs with other nucleotides. The base pairing allows a strand of RNA or DNA to act as a template in the synthesis of other nucleic acid molecules. Examples include the cellular processes of DNA replication (DNA is used as a template to make DNA), transcription (DNA is used as a template to make RNA), and reverse transcription (RNA is used as a template to make DNA).
Carbonyl
C=O
Which of the following would most likely occur if cattle lost the ability to maintain a colony of microorganisms in their digestive tract?
Cattle would no longer be able to use cellulose as a primary source of glucose. Why: Without the enzyme B produced by microorganisms in their digestive tract, cellulose would pass through the digestive tract without being digested.
A student wants to modify model 1 so that it represents an RNA double helix instead of a DNA double helix. Of the following possible changes, which would be most effective in making model 1 look more like RNA than DNA?
Changing the deoxyribose to riboses by adding −OH−OH groups Why:RNA contains ribose, whereas DNADNA contains deoxyribose. A ribose sugar has an −OH−OH group linked to the 2′2′ carbon that a deoxyribose sugar does not have
Process of dehydration synthesis
converts smaller molecules into larger ones by removing water
Nucleic Polymer
DNA and RNA
nucleic acids
DNA and RNA
Lipids
Energy-rich organic compounds, such as fats, oils, and waxes, that are made of carbon, hydrogen, and oxygen.
what bond connects monomers?
covalent bonds
Which of the following statements is correct about the molecule shown in Figure 1 ?
It is DNA because of the nucleotides present. Why: The figure indicates that one of the nucleotides is thymine. Thymine is found in DNA and not in RNA.
polar
Molecule with partial charges. Mixes with water.
Which of the following is common feature of the illustrated reactions showing the linking of monomers to form macromolecules?
Monomers are joined by a covalent bond, and a water molecule is produced. Why:The monomers of the two reactions illustrated are joined by covalent bonds with the production of a water molecule.
Hydroxyl
OH-
Which of the following describes a key difference among the 20 amino acids that are used to make proteins?
Some amino acids are hydrophobic. Why: Due to having non-polar R-groups, 10 of the 20 amino acids are hydrophobic. Interactions between hydrophobic amino acids play an important role in determining protein structure and function.
Based on Figure 1, which of the following best compares the atomic structures of starch and cellulose?
Starch and cellulose are composed of repeating glucose monomers; however, in cellulose every other glucose monomer is rotated 180 degrees. Why: Both starch and cellulose are both composed of repeating glucose molecules; however, the orientation of every other glucose in cellulose is upside down compared with the ones on either side.
How might this change affect the structure and function of the protein?
The R-groupR-group of the new amino acid, valine, has different chemical properties than the R-groupR-group of cysteine. This will cause the protein to misfold and not function properly in the cell. Why:Three-dimensional folding of a protein is due to interactions among the R groups of the amino acids. Cysteine has a sulfhydryl group, which may form a disulfide bridge with another part of the polypeptide chain. Valine has no sulfhydryl group and is nonpolar, which will affect how the polypeptide will fold.
As shown in Figure 1, an amino acid must have which of the following properties in order to be incorporated into a polypeptide?
The ability to form a covalent bond with both its NH2 group and its COOH group Why:An amino acid needs to participate in the formation of two peptide bonds in order to be part of a polypeptide. The first bond may occur when the NH2 group interacts with the COOH group of another amino acid. The second bond occurs when the COOH group interacts with the NH2 group of a third amino acid.
peptide bond
The chemical bond that forms between the carboxyl group of one amino acid and the amino group of another amino acid
Based the information provided, which of the following statements best describes why starch and cellulose provide different functions in plants?
The differences in the assembly and organization of the monomers of these two polymers result in different chemical properties. Why: The identical orientations of the glucose monomers in starch create a polysaccharide with alpha bonds that is easy to break down into glucose for energy use. The alternating orientations of the glucose monomers in cellulose create beta bonds that produce a rigid polymer that is difficult to digest for energy use.
DNA
double helix deoxyribose T-A (2 bonds) C-G (3 bonds)
Based on the figure, which statement best describes the observed relationship between atmospheric CO2enrichment and plant growth under ideal and stressed conditions?
The increase in atmospheric CO2 resulted in a greater increase in plant growth under stressed conditions than under ideal conditions. Why: Based on the figure, the increase in atmospheric CO2 resulted in a greater increase in plant growth under stressed conditions than under ideal conditions.
Which feature of model 1 best illustrates how biological information is coded in a DNA molecule?
The linear sequence of the base pairs. Why: The sequence of base pairs in a DNADNA molecule plays a central role in the coding of biological information.
Why are hydrocarbons insoluble in water?
The majority of their bonds are nonpolar covalent carbon-to-hydrogen linkages.
Carbohydrate functions
energy and structure
Which of the following is the most likely reason for the difference in leaf growth?
The phosphorus-starved plant was unable to synthesize both the required nucleic acids and lipids, limiting growth. Why: Phosphorus is used to make nucleic acids and certain lipids. Without phosphorus atoms, nucleic acids and lipids cannot be made for the plant to use for growth.
Which of the following best describes how the structure of ice benefits the organisms that live in the water below?
The water molecules in ice are farther apart than those in liquid water, so the ice floats, maintaining the warmer, denser water at the lake bottom. Why: The water molecules in ice are farther from each other than are water molecules in liquid water, so ice is less dense than liquid water and floats on its surface, while the denser water at 4 degrees Celsius sinks to the bottom, maintaining a steady temperature all winter.
Hydrophobic
Water fearing
Which of the following is a monomer used to build a biological polymer?
amino acid
Protein monomer
amino acids
addhesion
attraction between molecules of 2 different substances
amino acids
building blocks of proteins
4 major macromolecules
carbohydrates, lipids, proteins, nucleic acids
Properties of Carbon
carbon has 4 valence electrons, and can bond with other carbon atoms forming chains .
Carbohydrates elements
carbon, hydrogen, oxygen
Lipids are composed of
carbon, hydrogen, oxygen
Lipids elements
carbon, hydrogen, oxygen