Review for Exam #1
What is the effect that an enzyme and substrate have on the activation energy
- lowers activation energy - substrate have no effect
What are the properties of a molecule?
- made up of atoms - vary in size - 3D
List the 3 different types of cofactors and give an example of each
- metal ions (iron) - coeneymes (biotin) - prosthetic groups (heme)
In what way does a non-competitive inhibitor prevent an enzyme?
- shape change - turns off
Describe the role of a catalyst in a chemical reaction
- speed up reaction - lower activation energy
If you want to generate different reponses in separate cell types, but still use the same signal for the different responses, you
- use different second messengers in each cell - use different effectors in each cell
If you have a short fragment of DNA, and you have 12 cytosine and 13 adenine. What must be true for the rest of the fragment?
12 guanine, and 14 thymine
A section of DNA is seperated into its components and found to contain 140 adenine bases and 120 cytosine bases. Their base pairs include:
140 thymine bases and 120 guanine bases.
How many hydrogen bonds are there for this sequence: 5' - GCTTAC - 3'
15
Phosphodiester linkage connects what to a nucleic acid?
3' to 5' carbons
Which of the following statements is true about the molecule below?
A phosphodiester linkage is formed between the 3' and 5' carbons.
What are the functions of the cell membrane?
- communication - regulation - protection
What are the functions for carbohydrates?
- energy storage - structural - cell membrane connection
The function of cell membranes is to
- form compartments - isolate chemical reactions - aid in communication between cells - aid in energy transformation
List all the major events that changed organisms
- formation of cells (prokaryotes) - photosynthesis - aerobic metabolism - eukaryotic cells - multicellularity and specialization
What are the 7 characteristics of life?
- have common chemical parts - rely on interactions between their own parts and other organisms - convert enviromental molecules of biological molecules - extract energy from the environment to do work - contain genetic information and use it to reproduce - evolve - share similarities among genes
To increase the fluidity of the membrane, cells would need to do what?
- have more unsaturated fatty acids - increase temp
List the 3 different types of proteins that are embedded in the membrane
- integral - transmembrane - peripheral
You have found a polymer that has a 5-carbon sugar, the nitrogenous base thymine, and a phosphate group. What molecule is this and is it single or double stranded?
DNA; double
Tertiary level protein structures have what special bond/connection?
Disulfide Bridge
T or F: enzymes cause a reaction to occur
F; enzymes only cause a reaction to happen faster (slower activation energy)
T or F: Uniport moves 2 things in 1 direction
False; symport
The graph below shows the proportion of unsaturated fatty acids in the cell membranes of an earthworm. Based on the pattern shown, which explanation is the most likely for what is shown on the x-axis (horizontal)?
Five dates going from winter into summer
Nucleic acids and proteins are both polymers made of a set of monomers. Complete the following analogy: _______ are to nucleotides as side chains are to amino acids.
Nitrogenous bases
Which of the following would allow you to confirm that the V. cholerae cell was a prokaryote and not a eukaryote?
absence of a nucleus
In a healthy intestinal cell, active G-proteins interact with
adenylyl cyclase
What is a genome?
all genetic information in an organism
Which of the following is not a function of cell membrane proteins?
all of these are functions of cell membrane proteins - transport - cell recognition - cell to cell signaling - receptor mediated endocyosis
A type of reaction would be used to connect momomers when building all macromolecules except for a lipid is?
condensation reaction
In a _____ reaction, water is removed and polymers are ____ but in _______ reactions water is added to ______ polymers
condensation, built; hydrolysis, break
Membrane proteins that use passive transport include all but which of the following?
cotransporters
Nucleotides in RNA are connected to one another in the polynucleotide chain by _______ bonds between _______.
covalent; a sugar and a phosphate group
How does concentration gradient work?
drive things to enter or leave the cell. they want to reach equilibrium
A triglyceride is composed of a glycerol molecule attached to three molecules of:
fatty acids
The graph below shows the proteins of unsaturated fatty acids in the cell membranes of an earthworm. Based on the pattern shown, which explanation is the most likely for what is shown on the x-axis (horizontal)?
five dates going from summer into winter
What is the second law of thermodynamics?
free energy; energy is lost as reactions occur (entropy)
A fat contains fatty acids and
glycerol
What 3 things make up a triglyceride?
glycerol + 3 fatty acids
What are the 2 easy way to identify a lipid?
hydrocarbon chain (carbon rings) and methyl groups
Single-stranded RNA can fold back on itself creating 3D structures such as tRNA. These folds are stabilized by _____ bonds
hydrogen
Single-stranded RNA can fold back on itself, creating three-dimensional structures such as tRNA. The folds are stabilized by _______ bonds.
hydrogen
What is surfactant made out of?
hydrophillic heads and hydrophobic tails
Which functional groups are found in these molecules?
hydroxyl and keto
The lumen contains intestinal cells that are responsible for absorbing macromolecules and water from food. In order to collect water from the food, the intestinal cells must be _____ compared to the lumen
hypertonic
If you had a 2000 Na+ ions on one side of a semipermeable membrane and a 1000 Na+ ions on the other side, the 2000 side would be
hypertonic relative to the 1M side
The tertiary structure of a protein is determined by its
interactions among R groups.
In an anabolic reaction, energy is converted from _____ to _____
kinetic; potential
To which group of macromolecules do these belong to?
lipids
There are four types of biological macromolecules. Which of the following shows the relative amounts from the least to most common?
lipids, carbohydrates, nucleic acids, proteins.
Cell membranes are made up of mostly what macromolecule? What part does that macromolecule play?
lipids; cholesterol
Substances that are insoluble in water are most likely to have what type of molecular characterictics?
mainly non-polar bonds
what are the limitations of enzymes?
maximum rate is limited to the number of enzymes
A new biological chemical is isolated from an organism and is found to contain many C and H atoms in a non-polar region. The chemical is most likely a/an:
monosaccharide
An atom can change into an isotope by adding or subtracting _____, but changing the number of _____ will change the element
neutrons; protons
Which macromolecule is correctly matched with its function?
proteins; receptors for collecting cholesterol
According to the principle of complementary base pairing, purines always pair with
pyrimidines.
What is the difference between qualitative and quantitative?
qualitative - descriptive (color) quantitative - exact measure (13 kg)
A general function of all cellular membranes is to
regulate which materials can enter or leave the cell.
describe the difference between saturated lipids and unsaturated lipids
saturated: single bonds & can be packed closely together making them solid at room temp unsaturated: double bonds that wont allow to be closely packed together making them liquid at room temp
A beta pleated sheet organization in a polypeptide chain is an example of _____ structure
secondary
DNA carries genetic information in its
sequence of bases
What can travel through the phospholipid bilayer in simple diffusion?
small, non-polar molecules
What is the importance of structure and function in biology?
structure affects the function
_____ protein structure gives molecules its 3D shape
teritary
Disulphide bridges are formed by side chain interactions; therefore, this level of structure is?
tertiary
When talking about the genetic language, "information" is stored in
the order of nucleotides in DNA
What do hydrogen and ionic bonds have in common?
they are both interactions among electrons
Cyclic adenosine monophosphate and adenosine triphosphate are examples of:
triglycerides
T or F: Some nucleic acids only exist as monomers
true
Adhesion occurs when _______. To stick to surfaces like trees, geckos use _______.
two different substances stick together; adhesion
Cohesion occurs when _______. To stick to surfaces like trees, geckos use _______.
two molecules of the same substance stick together; adhesion
The sodium-potassium pump:
uses ATP to move Na+ ions into the cell
The sodium-potassium pump
uses ATP to move Na+ ions out of the cell
What is a comparative experiment?
when you observe 2 things and are able to compare to see if there is a connection between the 2 observations (ex: high level of pesticide, decreasing frog population)
How would you increase the fluidity of a membrane?
Add/increase the number of unsaturated fatty acids
What null hypothesis were the authors trying to falsify in this study?
Air bubbles around setae have no effect on the gecko's ability to walk under water.
Which of the following is a function of proteins?
All of these are protein functions
Stark et al. summarized their measurements in in a bar graph and a table. This represents which stage of the scientific method?
Analyzing results.
Active transport differs from facilitated diffusion because facilitated diffusion
C and D
What is the best description of setae?
C and D.
Which part of the compound above will not form hydrogen bonds with water?
C-H ring
What is the difference between catabolic and anabolic reactions?
Catabolic: break down potential to kinetic; exergonic Anabolic: build kinetic to potiential; endogonic
What is the difference between condensation and hydrolysis reactions?
Condensation: pulls water to link the 2 together Hydrolysis: adds water to break apart
Which of the following statements about DNA and RNA is false?
DNA is a polymer, whereas RNA is a monomer.
Describe the Central Dogma in biology
DNA transcribed -----> RNA translated -----> to form proteins; DNA also replicates
What happens in a hydrolysis reaction?
H2O is added to a macromolecule to split
What is the difference between a hypothesis and a prediction?
Hypothesis: a proposed explanation or statement Prediction: an "if... then" statement
In this assignment, the image of the gecko setae came from which scientific journal?
It came from someone's website.
What is the difference between the ligand and voltage gated channels?
Lingand: controlled by something binding to the channel protein Voltage: controlled by the charged differences inside and outside the cell
List the biological macromolecules from least common to most common
Lipid --> carbohydrate --> nucleic acids --> proteins
In the scientific method, this statement would fall under which step: Doctors are finding that Neisseria gonorrhoeae, is showing increased resistance to antibiotics
Observation
Stark et al. harnessed geckos to a force detector. Then, they submerged the geckos feet in water and measured the force they could generate. These steps represent which stage of the scientific method?
Performing an experiment
What type of bond hold individual sequential nucleotides together?
Phosphodiester
What are the examples of polar and non-polar bonds?
Polar: H-O, C-O, N-H, P-O Non-Polar: C-C, C-N, C-H
What part of the scientific method is this: If implanting an electron device can detect changes in neurons, then it will reduce the frequency on seizures
Prediction
Explain the difference between primary and secondary active transport
Primary: uses ATP directly Secondary: primary happens to cause a concentration in order to move a new substance into the membrane
Name the purines and pyrimidines
Purines: G, A Pyrimidines: C, T, U
Give an example of Quantitative Data and Qualitative Data
Quantitative: humans have 10 fingers Qualitative: bird is red
Amino acids can be classified into different categories according to what feature?
R-groups/ side chains
A fundamental difference between DNA and RNA is that:
RNA contains uracil, while DNA contains thymine
A fundamental difference between RNA and DNA is that:
RNA contains uracil, while DNA contains thymine
What is the nucleotide sequence of the complementary strand of the following DNA molecule: A A T G C G A?
T T A C G C T
If you had the RNA sequence AAGC, the complementary DNA sequence would be
TTCG
Which of the following statements is true about nucleic acids?
The 3' carbon in the RNA monomer has a hydroxyl
Which of the following statements about lipids is false?
They are readily soluble in water.
All of the following bases are found in DNA except
Uracil
T or F: Water passes through the cell membrane using active transport
Uses facilitated diffusion through aquaporins
An anabolic reaction is _____. A catabolic reaction is _______
anabolic: endergonic catabolic: exergonic
When a chemical reaction occurs that joins two monomers, then
atoms in the reactants may share electrons with different atoms in the products.
What does an activator enzyme do?
bind to a part of the enzyme to open up the binding site for the substrate
In condensation reactions, the atoms that make up a water molecule are derived from
both reactants
The molecule shown below belongs to the _____ group of macromolecules and, the arrows are pointing to______.
carbohydrate; an ester linkage
Converting from potential energy to kinetic energy is what type of reaction?
catabolic
Which of the following is not a role of lipids?
cell wall structure
Amino acids can be classified by the
characteristics of their side chains, or "R" groups
The illustration below shows a transmembrane protein embedded in the plasma membrane. What propertied would you expect many amino acids of this protein to have at the location labeled with an X?
non-polar hydrophobic
Hydrophobic areas go with ______ molecules; Hydrophilic areas go with _____ molecules
non-polar; polar
ATP is used as a temporary store for energy and can best classified as a type of:
nucleotide
What are the steps of the scientific method?
observe --> question --> hypothesis --> prediction --> experiment --> result
Function proteins are often flexible and can change their shape because:
of weak interactions between different polypeptide chains
Functional proteins are often flexible and can change their shape because:
of weak interactions between different polypeptide chains
DNA and RNA both include
pentoses.
When building an RNA molecule, we form _____ linkages on the ____ and ____ carbons
phosphodiester linkage; 3' ---> 5' or 5' ---> 3'
What is the role of feedback in a system?
positive feedback accelerates a process while negative feedback inhibits the process
Which of the biological macromolecules is represented in the diagram below?
protein