Biology 101: Final Exam
In animals, ______ is largely composed of extracellular matrix
Cartilage
When an atom loses an electron to another atom, it results in formation of
Cations and anions that can form ionic bonds
The process through which cells can detect and respond to signals in their extracellular environment is called
Cell communication
___________ is a polymer of glucose
Cellulose
G protein coupled, enzyme-linked, and ligand-gated ion channel receptors are similar in that they
Change their conformation when bound to a hormone.
During photosynthesis the reactants, carbon dioxide and water, can become glucose and oxygen. Glucose and oxygen can also be reactants to form water and carbon dioxide. If the two reactions are working at a constant rate this would form a
Chemical equilibrium
Where does the Calvin cycle occur?
Chloroplast stroma
You measure the amount of enzyme activity in the presence of X and note that as you add more substrate the amount of enzyme activity increases. This indicates that the compound X is an
Competitive inhibitor
1 mole = 1000 millimoles (mmol); 1millimole = 1000 micromoles (µmol). If a solution contains 38231 µmol, what is that amount in mmol?
(38,231/1000) = 38.231 mmol
Some cells alter their surface area to volume ratio by increasing their size or altering their shape. A classic example of this change is
Cuboidal epithelial cells
High energy electrons from molecules of NADH and FADH2 are transferred to a chain of proteins within the electron transport chain. What is the final protein in the electron transport chain?
Cytochrome oxidase
Which of the following correctly describes bases that pair with each other in the DNA double helix?
Cytosine bonds with guanine
Collecting data without a specific hypothesis in mind is called
Discovery-based science
True or False: Auxin is a plant hormone that causes cells to shorten and allow plant growing tips to move toward the sun.
False
True or False: Cellulose in the cell wall is a primary energy store for plants.
False
True or False: Cyclic AMP activates protein kinase C in producing a cell response
False
True or False: For a reaction to be spontaneous it must show a net decrease in both energy and entropy.
False
True or False: In prokaryotic cells, the electron transport system occurs in the mitochondria
False
True or False: Materials move in and out of the nucleus via endocytosis and exocytosis
False
True or False: Metabolism refers to only those reactions that release energy.
False
True or False: Most enzymes or bioactive molecules work effectively within a broad range of pH.
False
True or False: Osmosis describes the movement of water from an area of high to low solute concentration
False
True or False: Saturated fats are composed of fatty acids with several double bonded carbons
False
True or False: Table salt forms from sodium and chloride via hydrogen bonding
False
True or False: The genome has more influence on the function of cells in different organs than does the proteome.
False
True or False: The modification of a limb that was used for walking in a preexisting ancestor to one that is used as a wing for a species today is called biological organization.
False
True or False: The proton motive force requires that the H+ concentration is lower in the intermembrane space than inside the matrix.
False
True or False: The sole function of carbohydrates is to serve as energy stores.
False
True or False: all amino acids within a protein are either polar charged or polar uncharged
False
True or False: in hot and arid environments, plants that maximize photorespiration produce the Most sugars
False
True or False: one gram of hydrogen, which has an atomic mass of 1, would have fewer atoms than 1 gram of carbon that has an atomic mass of 12.
False
True or False: the Calvin cycle is only capable of fixing carbon dioxide in the dark
False
What structural component makes fat an efficient macromolecule able to store large amounts of energy?
Fats have long chains of C-H bonds, which store large amounts of energy.
Multiple functional groups are able to attach to macromolecules. What is the most useful characteristic that enables the attachment of multiple functional groups?
Four carbon covalent bonds
Which signaling molecule is composed of a, b, and y subunits?
G protein
Changes in _____ represent the predominant cause for biological evolution
Genetic makeup
New species evolve from pre-existing species by the accumulation of
Genetic mutations
Our species is called Homo sapiens. The first word refers to which taxonomical grouping?
Genus
The functional group that characterizes an alcohol is
-OH
The functional group that forms a covalent bond between peptide chains and stabilizes protein tertiary structure is
-SH
When an atomic mass of 16 and an atomic number of 8, it follows that oxygen_______
1) Has 8 electrons 2) Has 16 neutrons 3) Can readily form bonds with 2 other atoms
Lipids in the form of triglycerides, phospholipids, steroids, and waxes are all important for life to occur. What processes relate to lipid function?
1) Hormone production 2) Energy storage 3) Cell formation 4) Prevention of water loss
When performing hypothesis testing , the steps that most accurately describe the process you must go through include ______
1) Observe a natural phenomena 2) Develop hypothesis to explain phenomena 3) Design experiments to determine if predictions are correct or not 4) Analyze data to support or reject hypothesis
What is the appropriate order of the stages of investigating whether maple trees drop their leaves in the autumn because of colder days?
1). Observation that maple leaves drop their leaves in autumn. 2). Hypothesis is that maple trees drop their leaves because of colder temperatures. 3). Maple trees are grown in two greenhouses where the only variable is temperature.(15 C vs. 10 C) 4). There is no statistical difference in the number of leaves dropped at 10 C as compared to 15 C. 5). The hypothesis is rejected.
Which order best fits the way in which you would conduct the five stages of scientific method?
1).Observe a natural phenomenon 2).Develop a hypothesis 3).Design an experiment with predictions 4).Analyze data 5).Confirm or reject hypothesis
A phospholipid has ____ fatty acids attached to glycerol, whereas a fat has______
2; 3
Tritiated hydrogen (3H) differs from hydrogen (1H) in that
3H has 2 more neutrons than 1H
Energy is carried from the light reaction to the carbon reaction by
ATP
What are the final by-products of glucose oxidation during aerobic cell respiration?
ATP, heat, and carbon dioxide
When NADP+
Accepts electrons in the light reaction, it is reduced to form NADPH
How might a plant cell compensate for the excessive membrane fluidity that occurs during prolonged exposures to elevated temperature?
Alter the lipid composition to have longer phospholipid tails and fewer double bonds
The production of second messengers in signal transduction offers at least two advantages, speed and
Amplification
Some anticancer drugs block signal transduction pathways activated by growth factors. Which would be a good target for such a drug?
An inhibitor of a protein kinase cascade
The addition of a strong acid like HCl to an aqueous solution would result in
Both the release of H+ and a decrease in pH
During exposure to elevated glucose, a yeast cell will increase its uptake of glucose. Describe the mechanism by which the yeast sense the extracellular glucose.
By glucose binding to glucose receptors
How can a living cell increase the rate of a chemical reaction?
By using a catalyst
CAM (crassulacean acid metabolism) plants such as cacti differ from standard C4 plants such as corn in which way?
CAM plants are limited to producing CO2 for the Calvin cycle during the day, while C4 plants produce CO2 for the Calvin cycle both during the day and at night
What process best characterizes Ca^2+ movement from the cytosol (low Ca^2+ concentration) into the endoplasmic reticulum (high Ca^2+ concentration)?
Calcium movement involves active transport
The feature of carbon important for producing a diversity of organic molecules is _______
Carbon can form both polar and non polar covalent bonds with various elements
The formation of the complex molecules in living organisms is made possible by what property of carbon?
Carbon forms up to 4 covalent bonds
What processes will occur in the presence or absence of oxygen?
Glycolysis
A new flower species has a unique photosynthetic pigment. The leaves of this plant appear to be blue-green. What wavelengths of visible light does this pigment reflect?
Green and Blue
Water.....
Has cohesive properties
Eukaryotes differ from prokaryotes, in part because eukaryote cells
Have a membrane-bound nucleus
The best descriptive comparison between hemidesmosomes and desmosomes is
Hemidesmosomes anchor cells to the ECM while desmosomes anchor cells to other cells
Which organism consumes organic molecules to live?
Heterotrophs
Scientists working on an arctic glacier discover a population of microbes living in frigid temperatures. Which component of the cell membrane might contribute to maintaining the fluidity of plasma membranes under freezing conditions?
High levels of unsaturated phospholipid tails within the lipid bilayer
Whether the external temperature is hot or cold, birds maintain an internal body temperature of approximately 40 degrees C. This is an example of________
Homeostasis
Fuels such as gasoline are non polar and have high potential energy because they are largely composed of
Hydrocarbons
The most abundant element in living organisms is
Hydrogen
The single element you would choose to remove from living organisms in order to remove the highest percentage of atoms would be _______
Hydrogen
Patients with Ehlers-Danlos syndrome have a defect in their ability to synthesize collagen. Predict the symptoms you would expect to have.
Hyper-flexible joints
The strongest chemical bonds are
covalent bonds
Isotopes are different forms of the same element that
differ in their number of neutrons
A bottle of sodium(Na) in solution and a bottle of chlorine(Cl) in solution are mixed together and the water evaporated. What type of bond will be created between the atoms, and what will be the product?
Ionic bonds; Table salt
What would happen to a plant that is treated with a chemical that prevents electrons from moving through the electron transport chain?
It could not generate an electrochemical H+ gradient across the membrane
What will happen to the pH inside a thylakoid that is exposed to light?
It will decrease
When grouping organisms, which classification is most general for a particular type of organism?
Kingdom
The structural difference between saturated and unsaturated fats causes what type of change at room temp?
Linear structure of a fatty acid causes solid formation at room temp.
The major class of macromolecules that stores energy and makes up the major component of plasma membranes are
Lipids
A plant will begin flowering in response to changes in length of daylight, temperature, and light quality. This is an example of which unifying principle of life?
Living organisms interact with their environment
The cytoskeletal structure(s) that are composed of actin and regulate cell shape, cell movement, and muscle contraction include
Microfilaments and microtubules
The organelle that best enables an athlete's tissues to be metabolically active are
Mitochondria
Energy released by the electron transport chain is used to pump H+ into which location?
Mitochondrial inter membrane space
Blue light ___________ energy than red light and is _________ by a green leaf.
More; absorbed
If the concentration of a ligand is 100 times greater than kd of its receptor, ____________ of the receptors will be bound to a ligand.
Most
What feature of genetic mutations can eventually lead to the evolution of a new species?
Mutations produce changes in the DNA sequence of a gene.
The molecules that directly convert NADP+ to NADPH is/are
NADP reductase
Na+ ion concentrations are higher outside the cell than inside the cell. What type of transport system is required to move Na+ ions in and out of the cell?
Na+ moves into the cell by facilitated diffusion and out of the cell by active transport
A plant performing photosynthesis will ______
Produce oxygen and consume carbon dioxide
The macromolecules that can accomplish the widest range of biological functions are
Proteins
The enzyme responsible for converting pyruvate to acetyl CoA is called
Pyruvate dehydrogenase
The molecule that is polar and acts like a base is
R-NH2
Which macromolecule did the majority of scientists favor as the "first" to be found in protobionts?
RNA
When Melvin Calvin and colleagues injected 14^C labeled CO2 into cultures of green algae, what led him to conclude that rubisco adds CO2 to ribulose bisphosphate in the Calvin cycle?
Radioactivity appeared last in ribulose bisphosphate
A substrate binding to an enzyme is most similar to a signal molecule binding to a
Receptor
Using 14^CO2 as a radioactive tracer, which molecule would be the last to incorporate 14^C within the Calvin cycle?
Ribulose biphosphate (RuBP)
Why would a diet containing unsaturated fats that form triglycerides be better for an athlete when considering energy levels and health?
Saturated fats are packed closer together, making their breakdown for energy release less efficient and forming unnecessary fat deposits
When designing a butter with a higher ratio of unsaturated to saturated fats you would need to take care not to remove all saturated fats. What is the main reason for this?
Saturated fatty acids are linear in structure and form closely packed structures that are more solid at room temp.
To observe the three-dimensional structure of a cell the best type of microscopy would be
Scanning electron microscopy
A protein's _______ structure contains helixes and sheets that result from hydrogen bonding between carboxyl and amino groups of the polypeptide chain.
Secondary
Sodium concentrations are higher outside and glucose concentrations are higher inside the cell. Using the same membrane protein for Na+ and glucose transport, what is it called when a Na+ electrochemical gradient is used to drive glucose transport into the cell against its concentration gradient?
Secondary active transport
Diabetics can be given insulin that binds to receptors on cells throughout the body increasing glucose uptake. Insulin is an example of a
Signal
After a night of drinking too much alcohol, a person will rely on which organelle to help detoxify and recover?
Smooth endoplasmic reticulum
The main structure for gas exchange in plants is called the
Stomata
The movement of sucrose and H+ into the cell by the same membrane protein reflects the actions of what type of transporter?
Symporter
The most accurate nucleotide base composition of the DNA double helix is ______. (T=thymine, A= adenine, C=cytosine, G=guanine)
T+G=A+C
The grouping or classification of species is termed
Taxonomy
What happens immediately after signaling molecule binds to its G protein- coupled receptor(GPCR)?
The G protein exchanges GDP for GTP, and becomes activated.
Cell surface molecules are labeled with a fluorescent tag and then a portion of them are bleached with a laser beam. What would one observe after the cell is incubated for a few minutes?
The bleached molecules would diffuse laterally through the membrane and intermix with unbleached molecules.
A researcher decides to test the scientific validity of the common phrase " An apple a day keeps the doctor away". What would be a valid hypothesis to investigate this specific question?
The daily consumption of a singe apple does not change the number of visits to the doctor.
You are injecting a dye into a eukaryotic cell to detect a specific functional enzyme in the cytosol. Where would you need to inject the dye?
The dye would go between the plasma membrane and membranes of the organelles.
In the reaction, 6CO2 + 6H2O →C6H12O6 + 6O2, which side should energy be placed on?
The left side as this is an endergonic reaction.
The atomic number of an atom is
The number of protons in the atom
Which is an immediate effect of blocking the activity of mitochondrial ATP synthase?
The pH in the space between the mitochondrial membranes would decrease
What makes phospholipids good at forming cellular membranes?
The polar and non polar regions create an amphipathic bilayer of phospholipids.
Five unknown compounds are added to water. 4 of the compounds go into solution while one does not. What property does water possess that allows these 4 compounds to dissolve? Why might the 5th compound not dissolve?
The positive and negative charge in water will dissolve many substances; the substance is not structurally similar to water.
You design a drug that transforms skin cells into cells that secrete insulin. Which cellular aspect is the drug most likely to affect?
The proteome
The general structural and functional differences between a nerve and smooth muscle cell within an individual are a result of
The proteome and the relative amounts of certain proteins that differ between muscle and nerve cells
"All living organisms are composed of cells" is best related to what kind of scientific statement?
Theory
An explanation for a biological process that is substantiated by a large body of evidence is called a
Theory
After estrogen binds to receptors, these estrogen receptors become activated
Transcription factors
Which membrane component is most important for allowing large, charged molecules to pass through the membrane?
Transmembrane proteins
In order to visualize the fine structure of viruses and cytoskeletal filaments at 10-25 nanometers in diameter the type of microscopy that would be most effective is
Transmission electron microscopy
A pharmaceutical company wants to design a small drug that will bind to a target on the outside of a cell and initiate a conformational change, allowing the drug to enter the cell through the target protein. Good targets for this purpose would be
Transporters
True or False: All tissues are composed of cells
True
True or False: Catabolic and anabolic reactions in living cells involve the transfer of electrons from one molecule to another in reduction-oxidation reactions.
True
True or False: Cells can sense changes in the environment through alterations in the extracellular matrix
True
True or False: Diffusion is the movement of a molecule from an area of high to low concentration
True
True or False: Fluorescence microscopy enables researchers to label and visualize a particular type of cellular protein or organelle
True
True or False: Glycosaminoglycans and proteoglycans resist compression and are found in large in large abundance in joints of the body.
True
True or False: If lithium has an atomic number of 3 then it will have 1 valence electron.
True
True or False: If oxygen is present, pyruvate will be converted to acetyl CoA in the mitochondrial matrix
True
True or False: Ion gradients across the membrane drive numerous cellular functions.
True
True or False: Photons from light can boost an electron to a higher energy state.
True
True or False: Sulfur-35 (35S) is an isotope of 32S. These elements differ in their number of neurons.
True
True or False: The electronegativity of an atom is a measure of its ability to attract electrons to its outer shell from another atom.
True
True or False: The presence of integral proteins allows membranes to be selectively permeable to certain molecules.
True
True or False: because carbon and hydrogen share similar electronegativities, they will form non polar covalent bonds with each other.
True
True or False: proteins can have separate domains with distinct structures and functions.
True
True or False: when table salt dissolves in water, the salt is called the solute
True
The function of a cell is related to the amount of surface area it has. Is this statement true or false and why?
True: A cell with the same mass can increase surface area with structures like microvilli that enhances absorption functions.
A phosphatase is capable of dephosphorylating molecules. What would this enzyme do in a signal transduction pathway that used a kinase cascade?
Turn off the cascade
The specialized structure that stores pigments, water, inorganic ions and maintains turgor pressure is the
Vacuole
A variety of finch species within the Hawaiian islands have acquired different types of beaks needed for utilizing specific food resources. what is the likely process by which these different species of finches came about?
Vertical Descent with mutation
If a C3 plant that normally closes its stomata during hot, dry conditions were triggered to open them instead, the most likely outcome would be that
Water leaves the leaf, decreasing the rate of photosyntesis
Carbohydrate assembly occurs by
a dehydration reaction between monosaccharides that form polysaccharides and disaccharides
A protein with multiple alpha helices is associated with the plasma membrane, and it can be isolated only by treating the membrane with a strong detergent. The protein is most likely
a transmembrane protein
If orange juice has a pH of 4 then it can be described as
an acidic solution
The first, innermost energy shell of an atom
can have a maximum of 2 electrons
A pesticide has been found to have a negative effect on different cell types. In some plants it stops the formation of root nodules and in humans it can stop macrophage from taking up bacteria and generally stops cells from taking up protein-bound nutrients. The cellular function most likely affected is
endocytosis
The release of the protein insulin from pancreatic cells occurs by
exocytosis
Following a meal, glucose must move from the gut lumen where there is a high glucose concentration into the intestinal cell where there is a relatively low level of glucose. This movement is called
facilitated diffusion
A significant role played by pH buffers is to
limit major shifts in the amount of H+ and OH-
The primary function of an enzyme or any biological catalyst is to
reduce the energy of activation and increase the rate of a reaction
The ATP made during glycolysis is generated by
substrate-level phosphorylation
Boa constrictors on an island are an example of a/an__________
Population
Which level of organization includes all of the other levels?
Population
The nucleus of an atom is composed of
Portons and neutrons
The primary advantage C4 plants have over C3 plants is that
C4 plants minimize photorespiration compared with C3 plants
______ bind two or more ions or molecules and transport them in opposite directions across a membrane.
Antiporters
Imagine that a cell can be treated with a drug that prevents proteins from undergoing large conformational changes. Which transport proteins would be unaffected by this drug treatment?
Aquaporin
Plants require a lot of water for transpiration, metabolism, and photosynthesis. How is water used in photosynthesis?
As an electron donor
In life, which is the simplest of all levels of organization?
Atom
Molecules are made up of
Atoms
A cell responds to a signal it sent. This is an example of
Autocrine signaling
A cell secretes a growth factor that binds to receptors on its own membrane preventing it from proliferating. This is an example of
Autocrine signaling
The phenomenon through which populations of organisms change over several generations is termed
Biological
The organelles most likely to have the ability to divide and reproduce themselves like a cell would be
Both mitochondria and chloroplasts
Some tissues need to be able to expand and contract, such lungs during breathing and intestines during digestion. Predict which ECM protein would be abundant in these tissues.
Elastin
Which domain of life contains the most multicellular organisms?
Eukarya
A green plant is first grown in blue light and then in green light. The likely outcome for photosynthesis in both phases is
Increased plant growth in blue light and no plant growth in green light
After being fed glucose, a cell increases its intracellular glucose concentrations by
Increasing membrane glucose transporters.
Epinephrine blocks the contraction of muscles in the airways. What other activities of epinephrine is most likely to be regulated by the same type of pathway?
Inhibition of saliva production in salivary glands.
How did the difference in oocytes placed in a hypotonic solution that had the CHIP28 mRNA injected compared to the control oocytes that were not injected indicate to Agre and colleagues that CHIP28 was related to the diffusion of water?
Injected oocytes swelled faster than control oocytes indicating CHIP28 facilitated the diffusion of water.
Signals can be sent from the ECM to the cell through _______.
Integrins
A fabric company wants to create a new material that is able to withstand high levels of tension. What cytoskeletal structure could they investigate to inspire the engineering of this new fabric?
Intermediate filaments
You have been asked to synthesize a new isotope for cadmium. Which part of the original atom would you need to manipulate in order to create an isotope?
Neutrons
Carbon and hydrogen have similar electronegativities and combine together to form hydrocarbon molecules. What type of bonds form between these atoms?
Nonpolar covalent
The nucleus is to eukaryotes as the _______ is to prokaryotes
Nucleoid
An amino acid is to a protein as a ______ is to a nucleic acid
Nucleotide
Mutations that inhibit the function of photosystem I but not photosystem II would result in a plant cell that could still generate
O2, ATP, and NADP+
A flower on a plant represents the _______ level of organization
Organ
A cell secretes a growth factor that binds to receptors on neighboring cells causing them to proliferate. This is an example of
Paracrine signaling
What are the two major components of cell membranes?
Phospholipids and proteins
The organisms that most specifically utilize light energy to make organic molecules from inorganic molecules are
Photoautotrophs
The equation, 6CO2 + = C6H12O6 + 6O2, describes which process?
Photosynthesis
How might a plant cope with the fact that the Calvin cycle uses more ATP than NADPH, yet produces roughly the same amount of both energy intermediates in photosystems I and II?
Photosynthesis can revert from a linear to cyclic electron flow, producing more ATP than NADPH
All organisms in the kingdom _____ can perform photosynthesis
Plantae
Gap junctions in animal cells are most similar to ______ in plants?
Plasmodesmata
What type of bonds form from the unequal sharing of electrons?
Polar covalent
After ATP donates a phosphate group in a couple reaction, it becomes ADP. The ADP can be converted back to ATP in a(an) _______ reaction.
endergonic
The amount of available energy that can be used to do work is called
free energy
You inject a dye into a cell and observe that it moves into adjacent cells. This would occur through _________
gap junctions
When a neurotransmitter released from one neuron binds to a _____ on a second neuron, that neuron depolarizes and fires.
ligand gated ion channel
NADPH is produced by
light reactions alone
The substance most rich in unsaturated fats is
olive oil
how does a macrophage (immune cell) consume a bacteria?
phagocytosis
The major macromolecules of the ECM are
polysaccharides and proteins
In the reaction pyruvate + CoA + NAD^+ = acetyl CoA + CO2 + NADH
pyruvate is oxidized and NAD+ is reduced.
Altering the three dimensional structure of an enzyme might
prevent the substrate from binding the enzyme's active site
Succulent plants such as cacti or pineapple
produce a 4 carbon molecule in the first step of carbon fixation
You have engineered a new membrane protein in your lab that uses energy to transport a toxic solute out of a cell and against its gradient. This protein is therefore most like a
pump
