AP Biology: Unit 1&2 Questions
Which of the following effects is produced by the high surface tension of water? Lakes don't freeze solid in winter, despite low temperatures. A water strider can walk across the surface of a small pond. Organisms resist temperature changes, although they give off heat due to chemical reactions. Evaporation of sweat from the skin helps to keep people from overheating.
A water strider can walk across the surface of a small pond.
Which of the following is not a trace element in the human body? Iodine Zinc Calcium Iron
Calcium
An organic compound that is composed of carbon, hydrogen, and oxygen in a 1:2:1 ratio is known as a Carbohydrate Lipid Protein Nucleic Acid
Carbohydrate
Which of the following statements regarding carbon is FALSE? Carbon has the capacity to form polar covalent bonds with hydrogen Carbon has the ability to form covalent bonds with up to four other atoms Carbon has the capacity to form single and double bonds Carbon has the ability to bond together to form extensive branched or unbranched "carbon skeletons"
Carbon has the capacity to form polar covalent bonds with hydrogen
A team of biologists develop a new drug, and one team member hypothesizes that the drug is incapable of freely passing across the plasma membrane and requires the help of membrane proteins to enter cells. Alternatively, another biologist on the team hypothesizes that the drug can diffuse passively across the plasma membrane like O2 and CO2 can. Which of the following, if true about the drug, best supports the alternative hypothesis that the new drug will exhibit simple diffusion across plasma membranes? The drug is a small nonpolar molecule. The drug is a small charged molecule. The drug is a large polar molecule. The drug is a large charged molecule.
The drug is a small nonpolar molecule.
Describe how the phospholipids of a plasma membrane regulate the movement of large or polar molecules across the membrane. Explain how osmosis will affect animal cells when the cells are placed into an environment with a low water potential (high solute concentration).
The hydrophobic tails of the phospholipid fatty acids block the movement of large and polar molecules, which require protein channels to cross the membrane.Osmosis will cause an overall movement of water out of the cells and that the cells will shrink.
White blood cells engulf bacteria through what process? exocytosis phagocytosis pinocytosis osmosis
phagocytosis
34.) Carrot cores were placed in solutions of varying concentrations and were found to neither gain nor lose mass in a sucrose solution of 0.42M. Use this information to calculate the solute potential of the carrot cores to the nearest hundredth. The temperature of the solution is 25°C. *
-10.40 Bars
Which of the following statements best supports the claim that certain organelles within eukaryotic cells evolved from free-living prokaryotic cells? The cytoplasm of both eukaryotes and prokaryotes is surrounded by a plasma membrane. Eukaryotes and prokaryotes both contain ribosomes, but the ribosomes of eukaryotes are more complex in structure than those of prokaryotes. Eukaryotes exchange segments of internal membranes between the endoplasmic reticulum and Golgi apparatus, but prokaryotes have no such internal membranes. Some organelles contain their own DNA that is more similar to prokaryotic DNA in structure and function than to the eukaryotic DNA found in the cell's nucleus
Some organelles contain their own DNA that is more similar to prokaryotic DNA in structure and function than to the eukaryotic DNA found in the cell's nucleus
Plants store most of their energy for later use as Starch Unsaturated Fats Glycogen Sucrose
Starch
Which of the following descriptions best fits the class of molecules known as nucleotides? a nitrogenous base and a phosphate group a nitrogenous base and a pentose sugar a nitrogenous base, a phosphate group, and a pentose sugar a phosphate group and an adenine or uracil
a nitrogenous base, a phosphate group, and a pentose sugar
Large organic molecules are usually assembled by polymerization of a few kinds of simple subunits. Which of the following is an exception to this statement? a steroid cellulose DNA an enzyme
a steroid
Which of these systems is least likely to be at chemical equilibrium? a test tube of living cells a test tube of organic molecules, kept in the freezer a test tube of organic molecules dissolved in water, kept at room temperature a test tube of dead cells in water, kept at room temperature
a test tube of living cells
If the pH of a solution is increased from pH 5 to pH 7, it means that the concentration of H+ is twice (2X) what it was at pH 5. concentration of H+ is one-half (1/2) what it was at pH 5. concentration of OH- is 100 times greater than what it was at pH 5. concentration of OH- is one-hundredth (0.01X) what it was at pH 5.
concentration of OH- is 100 times greater than what it was at pH 5.
Simple diffusion and facilitated diffusion are related in that both require protein carriers depend on a concentration gradient occur via contractions of cytoskeletal elements attached to membrane proteins are endergonic processes and thus require the hydrolysis of ATP occur in eukaryotic cells but not in prokaryotic cells
depend on a concentration gradient
Which level of protein structure do the α helix and the β pleated sheet represent? primary secondary tertiary quaternary
secondary
What kinds of molecules pass through a cell membrane most easily? large and hydrophobic small and hydrophobic large polar ionic
small and hydrophobic
The complexity and variety of organic molecules is due to the chemical versatility of carbon atoms. the variety of rare elements in organic molecules. the fact that they can be synthesized only in living organisms. their interaction with water.
the chemical versatility of carbon atoms.
All of the following contain amino acids except hemoglobin. cholesterol. antibodies. enzymes.
cholesterol.
Predict what would happen to typical animal cells placed in 0.0 M and 1.0 M sucrose solutions, and explain your prediction.
0.0M (prediction--Gain water/mass, Swell/burst/lyse)Explanation--Cell is hypertonic to sucrose solution, sucrose solution is hypotonic to cell, water potential is greater in 0.0M environment, no cell wall, or cell moving toward equilibrium (isotonic). 1.0M (prediction--Lose water/mass, Shivel/crenate/Flaccid)Explanation--Cell is hypotonic to sucrose solution, sucrose solution is hypertonic to cell, water potential is greater inside animal cell, or cell moving toward equilibrium (isotonic).
Four blocks of phenolphthalein agar are placed in a vinegar solution. Which block would the vinegar solution penetrate most thoroughly into after fifteen minutes? Determine the surface area to volume ratio for this block, and round your answer to the nearest hundredth. Block A= 2cm X 4cm X 4cm, Block B= 2cm X 8cm X 4cm, Block C= 1cm X 8cm X 8cm, and Block D= 1cm X 1cm X 64cm.
4.03 because Block D has the highest surface area to volume ratio.
Which of these molecules is not formed by dehydration reactions? fatty acids disaccharides DNA protein
fatty acids
What is the difference between a molecule and a compound? There is no difference; the terms are interchangeable. A compound consists of two or more elements in a fixed ratio; a molecule has two or more covalently bonded atoms of the same or different elements. Molecules contain atoms of a single element, whereas compounds contain two or more elements. A molecule consists of two or more covalently bonded atoms; a compound contains two or more atoms held by ionic bonds.
A compound consists of two or more elements in a fixed ratio; a molecule has two or more covalently bonded atoms of the same or different elements.
Climates tend to be moderate near large bodies of water because A large amount of solar heat is absorbed during the gradual rise in temperature of the water Water releases heat to the environment as it cools The high specific heat of water helps to moderate air temperatures All of the above
All of the above
What contributes to the movement of water up the vessels of a tall tree? Cohesion Adhesion Hydrophilic cell walls All of the above
All of the above
Mitochondria are found in most eukaryotic cells and contain their own DNA and ribosomes that are similar to those typical of many prokaryotic cells. Which of the following statements is justified by these observations? The mitochondrion is the only location in which eukaryotic cells can synthesize ATP. An ancestral cell most likely engulfed anaerobic prokaryote in a relationship that proved beneficial for both cells. Mitochondrial membranes provide abundant surface area for reactions because of the infoldings called cristae. The mitochondrion plays a role in respiration, but it also stores the cell's extra mRNA.
An ancestral cell most likely engulfed anaerobic prokaryote in a relationship that proved beneficial for both cells.
Why is water such an excellent solvent? It forms ionic bonds with ions, hydrogen bonds with polar molecules, and hydrophobic interactions with nonpolar molecules It forms hydrogen bonds with itself It has a high specific heat and a high heat of vaporization As a polar molecule, it can surround and dissolve ionic and polar molecules
As a polar molecule, it can surround and dissolve ionic and polar molecules
Bromelain works by breaking the enzymes that cause browning into smaller molecules. Explain how the reaction that breaks up the enzymes occurs.
Bromelain acts by enabling the hydrolysis of the protein/polypeptide/amino acid chain, by breaking apart the peptide bonds holding the amino acids together(OR)The bromelain breaks the bond between the amino acids by using water as a reactant.
The pH of a solution determines the charge of certain R groups. The pH of pineapple fruit ranges from 3.5 to 5.2. Predict the effect on the activity of bromelain if it is used in a product with a pH of 11. Justify your prediction.
Bromelain will decrease(BECAUSE)The changes in pH will affect the interactions between amino acid R-groups in the enzyme, which will change the folding/shape of the enzyme and ultimately will change it's function.
4.) Aquaporins are channel proteins that facilitate the transport of water across the cell membrane. One group of researchers hypothesizes that without functional aquaporins, no water will be able to enter the cell. A different group proposes an alternative hypothesis, stating that even with nonfunctional aquaporins, a small amount of water will still cross the cell membrane. An experiment is set up in which plant cells with mutated (nonfunctional) aquaporins and plant cells with normally functioning aquaporins are both placed in distilled water. Which of the following data would support the alternative hypothesis? * Cells with functional aquaporins exhibit low turgor pressure and are hypertonic. Cells with functional aquaporins exhibit high turgor pressure and are hypotonic. Cells with mutated aquaporins exhibit an absence of turgor pressure and are completely plasmolyzed. Cells with mutated aquaporins exhibit moderate turgor pressure and are hypertonic.
Cells with mutated aquaporins exhibit moderate turgor pressure and are hypertonic.
Which of the following best summarizes the relationship between dehydration reactions and hydrolysis? Dehydration reactions assemble polymers, and hydrolysis reactions break down polymers. Dehydration reactions eliminate water from lipid membranes, and hydrolysis makes lipid membranes water permeable. Dehydration reactions can occur only after hydrolysis. Hydrolysis creates monomers, and dehydration reactions break down polymers
Dehydration reactions assemble polymers, and hydrolysis reactions break down polymers.
What is the most likely pathway taken by a newly synthesized protein that will be secreted by a cell? ER → Golgi → nucleus Golgi →ER →lysosome nucleus →ER →Golgi ER →Golgi →vesicles that fuse with plasma membrane
ER →Golgi →vesicles that fuse with plasma membrane
According to the "Acid Rain Monitoring Project" at the University of Arkansas, the pH measured at Dickson St. in Fayetteville on March 15, 2018, was near 5 and the pH measured at Beaver Lake on the same date was near 9. Determine to the nearest whole number, how many times greater the H+ ion concentration was at Dickson St. than at Beaver Lake.
Feedback 10, 000 (10x10x`10x10)There are 10, 000 more H+ ions!
Ice floats because Hydrogen bonding spaces the molecules farther apart, creating a less dense structure The formation of hydrogen bonds releases heat; warmer objects float It has a smaller surface area than liquid water It insulates bodies of water so they do not freeze from the bottom up
Hydrogen bonding spaces the molecules farther apart, creating a less dense structure
Why does ice float in liquid water? The high surface tension of liquid water keeps the ice on top. The ionic bonds between the molecules in ice prevent the ice from sinking. Ice always has air bubbles that keep it afloat. Hydrogen bonds stabilize and keep the molecules of ice farther apart than the water molecules of liquid water.
Hydrogen bonds stabilize and keep the molecules of ice farther apart than the water molecules of liquid water.
Plant cell walls are composed of cellulose, while fungal cell walls are composed of chitin. A group of scientists hypothesize that this difference means the cell wall has largely different functions in plant cells and fungal cells. Alternatively, another group of scientists hypothesize that despite their biochemical differences, plant and fungal cell walls serve similar functions. Which of the following observations would best support the alternative hypothesis described above? Plant cell walls are found just inside the plasma membrane, while fungal cell walls are found just beneath the plasma membrane. Some plant cells have secondary cell walls that confer additional rigidity, while fungal cells do not. In both plant cells and fungal cells, the cell wall surrounds the outside of the cell membrane. Photosynthesis occurs in plant cells, but it does not occur in fungal cells.
In both plant cells and fungal cells, the cell wall surrounds the outside of the cell membrane.
Which of the following statements is correct about diffusion? It is very rapid over long distances. It requires an expenditure of energy by the cell. It is a passive process in which molecules move from a region of higher concentration to a region of lower concentration. It is an active process in which molecules move from a region of lower concentration to one of higher concentration.
It is a passive process in which molecules move from a region of higher concentration to a region of lower concentration.
The CFTR protein is made up of 1,480 amino acids linked together in a chain. Some humans produce a version of the CFTR protein in which phenylalanine (an amino acid) has been deleted from position 508 of the amino acid chain. Which of the following best predicts how the amino acid deletion will affect the structure of the CFTR protein? It will have no observable effect on the structure of the CFTR protein. It will affect the primary structure of the CFTR protein, but the other levels of protein structure will not be affected. It will affect the secondary and tertiary structures of the CFTR protein, but the primary structure will not be affected. It will affect the primary, secondary, and tertiary structures of the CFTR protein.
It will affect the primary, secondary, and tertiary structures of the CFTR protein.
Carbon's valence of four most directly results from Its four electrons in the valence shell that can form four covalent bonds Its tetrahedral shape Its very slight electronegativity Its ability to form single, double, and triple bonds
Its four electrons in the valence shell that can form four covalent bonds
Changing the shape or morphology of the mitochondrial inner membrane can change the efficiency of mitochondrial function. Which of the following outcomes will most likely result from a change in the shape of the mitochondrial inner membrane from a highly folded surface to a smooth, flat surface? Mitochondria will become more efficient because the inner mitochondrial membrane will become more permeable to ions. Mitochondria will become more efficient because the total volume of the mitochondria will increase. Mitochondria will become less efficient because the inner mitochondrial membrane will become less permeable to large molecules. Mitochondria will become less efficient because the surface area of the inner mitochondrial membranes will decrease.
Mitochondria will become less efficient because the surface area of the inner mitochondrial membranes will decrease.
A typical bag of fertilizer contains high levels of nitrogen, phosphorus, and potassium but trace amounts of magnesium and calcium. Which of the following best matches the fertilizer component with the molecule in which it will be incorporated by organisms in the area? Nitrogen will be incorporated into nucleic acids. Phosphorus will be incorporated into amino acids. Potassium will be incorporated into lipids. Magnesium will be incorporated into carbohydrates.
Nitrogen will be incorporated into nucleic acids.
If ATP breakdown (hydrolysis) is inhibited, which of the following types of movement across cell membranes is also inhibited? Movement of oxygen into a cell Movement of water through aquaporins Passage of a solute against its concentration gradient Facilitated diffusion of a permeable substance
Passage of a solute against its concentration gradient
Which of the following statements best explains the processes of passive and active transport? Passive transport is the net movement of substances down a concentration gradient that requires metabolic energy. Active transport is the movement of substances up a concentration gradient that does not require energy. Passive transport is the net movement of substances down a concentration gradient that does not require metabolic energy. Active transport is the movement of substances up a concentration gradient that requires energy. Passive transport is the net movement of substances up a concentration gradient that requires metabolic energy. Active transport is the movement of substances down a concentration gradient that does not require metabolic energy. Passive transport is the net movement of substances up a concentration gradient that does not require metabolic energy. Active transport is the movement of substances down a concentration gradient that requires energy.
Passive transport is the net movement of substances down a concentration gradient that does not require metabolic energy. Active transport is the movement of substances up a concentration gradient that requires energy.
The polar covalent bonds of water molecules Help water to dissolve nonpolar solutes. Lower the heat of vaporization and lead to evaporative cooling. Promote the formation of hydrogen bonds. Create a crystalline structure in liquid water.
Promote the formation of hydrogen bonds.
A major distinction between prokaryotes and eukaryotes is the presence of membrane-bound organelles in eukaryotes. Describe the structure and function of TWO eukaryotic membrane-bound organelles other than the nucleus.
Smooth ER: Is a network of folded membranous material that lacks ribosomes. Funciton is to synthesize lipids, metabolize carbohydrates, detoxify poisons, drugs, and alcohol, and store calcium ions. Golgi Apparatus: Is known as the shipping and receiving center of the cell. It is made up of flattened membranous sacs called cisternae that are arranged in stacks that have polarity. Its function is to modify products that come from the endoplasmic reticulum, manufacture certain macromolecules, and store and packages materials into transport vesicles.
Which of the following statements correctly describes the normal tonicity conditions for typical plant and animal cells? The animal cell is in a hypotonic solution, and the plant cell is in an isotonic solution. The animal cell is in an isotonic solution, and the plant cell is in a hypertonic solution. The animal cell is in a hypertonic solution, and the plant cell is in an isotonic solution. The animal cell is in an isotonic solution, and the plant cell is in a hypotonic solution.
The animal cell is in an isotonic solution, and the plant cell is in a hypotonic solution.
Cholesterol is an important component of animal cell membranes. Cholesterol molecules are often delivered to body cells by the blood, which transports the molecules in the form of cholesterol-protein complexes. The complexes must be moved into the body cells before the cholesterol molecules can be incorporated into the phospholipid bilayers of cell membranes. Based on the information presented, which of the following is the most likely explanation for a buildup of cholesterol molecules in the blood of an animal? The animal's body cells are defective in exocytosis. The animal's body cells are defective in endocytosis. The animal's body cells are defective in cholesterol synthesis. The animal's body cells are defective in phospholipid synthesis.
The animal's body cells are defective in endocytosis.
A spherical bacterial cell has a radius of 3um. The human egg cell has a radius of 100um. Which statement correctly indicates the cell that is able to more efficiently exchange materials with the external environment and provides a correct explanation? The egg cell, because it has the smallest surface-to-volume ratio. The egg cell, because it has the largest surface-to-volume ratio. The bacterial cell, because it has the smallest surface-to-volume ratio. The bacterial cell, because it has the largest surface-to-volume ratio.
The bacterial cell, because it has the largest surface-to-volume ratio.
Intravenous (IV) solutions administered to patients are normally isotonic. Which of the following is most likely if an IV of distilled water is administered to a patient? The cells that are exposed to hypotonic solutions will shrink as a result of salt moving into the blood. The liver will secrete additional bile salts into the blood to raise the tonicity of the administered fluid. The cells that are exposed to hypotonic solutions will expand as water moves osmotically into the cells from the blood. The patient's respiration rate will slow to compensate for the higher levels of circulating blood.
The cells that are exposed to hypotonic solutions will expand as water moves osmotically into the cells from the blood.
Which of the following is true of both starch and cellulose? They are both polymers of glucose. They are cis-trans isomers of each other. They can both be digested by humans. They are both used for energy storage in plants.
They are both polymers of glucose.
Organelles such as mitochondria and the endoplasmic reticulum have membranes that compartmentalize reactions and other metabolic processes. To function properly, the organelles must move substances across their membranes. Which of the following statements describes a feature shared by mitochondria and endoplasmic reticulum that increases the efficiency of their basic functions? They have rigid, nonfluid membranes. They have highly folded membranes. They have membranes composed of many carbohydrates. They have double membranes, with one membrane enclosed within the other.
They have highly folded membranes
The stems and fruits of pineapple plants contain a group of protein-digesting enzymes collectively called bromelain and are often used as an antibrowning agent for fruits and vegetables. Fruits and vegetables brown when they are bruised during transport or sliced and exposed to air. This browning is controlled by enzymatic pathways that produce brown pigments. The browning of fruits and vegetables reduces the nutritional value of the food, so antibrowning agents such as bromelain are used. Identify the type of monomer of which this enzyme is composed.
amino acids are the monomers
About 25 of the 92 natural elements are known to be essential to life. Which four of these 25 elements make up approximately 96% of living matter? carbon, sodium, hydrogen, nitrogen carbon, oxygen, phosphorus, hydrogen oxygen, hydrogen, calcium, nitrogen carbon, hydrogen, nitrogen, oxygen
carbon, hydrogen, nitrogen, oxygen
A cell is treated with a drug that prevents the formation of new lysosomes. The cell continues to transcribe the genes that code for the hydrolytic enzymes that are normally found in lysosomes and continues to translate the mRNAs for those proteins on membrane-bound ribosomes. The hydrolytic enzymes are most likely to accumulate in which of the following cellular structures? Nucleus Mitochondrian Smooth Endoplasmic Reticulum Golgi Complex
golgi complex
All of the following cell components are found in prokaryotic cells EXCEPT DNA ribosomes cell membrane nuclear envelope enzymes
nuclear envelope
Which of the following is a major cause of the size limits for certain types of cells? limitation on the strength and integrity of the plasma membrane as cell size increases the difference in plasma membranes between prokaryotes and eukaryotes evolutionary progression in cell size; more primitive cells have smaller sizes the need for a surface area of sufficient area to support the cell's metabolic needs
the need for a surface area of sufficient area to support the cell's metabolic needs
Humans and mice differ because their cells have different small organic molecules. their cells make different types of large biological molecules. their cells make different types of lipids. their cells have some differences in the sequence of nucleotides in their nucleic acids.
their cells have some differences in the sequence of nucleotides in their nucleic acids.
The tertiary structure of a protein is the bonding together of several polypeptide chains by weak bonds. order in which amino acids are joined in a polypeptide chain. unique three-dimensional shape of the fully folded polypeptide. organization of a polypeptide chain into an α helix or β pleated sheet.
unique three-dimensional shape of the fully folded polypeptide.