AP Bio Unit 2- Study Guide
contractile vacuoles
A membranous sac that helps move excess water out of the cell.
In what way do the membranes of an eukaryotic cell vary?
Certain proteins are unique to each membrane.
Cell reproduction
Nucleus, DNA, centioles
Which structure is common to plant and animal cells?
mitochondrion
In mitochondria, exergonic redox reactions
provide the energy that establishes the proton gradient.
Which of the following is a hydrophobic material?
wax
EXPLAIN how membranes participate in 3 of the following biological processes (1)
1. Muscle contraction- Motor neuron or axon terminal releases neurotransmitter or acetylcholine ACh (idk what this is y'all); ACh binds to receptors; Depolarization or Na+ moves in through membrane channels or depolarizes; Depolarization changes permeability of sarcoplasmic reticulum (SR) or Ca2+ released from SR; Ca2+ active transport into SR; Repolarization or maintenance of membrane potential (Na+/K+ pump); Smooth or cardiac muscle gap junctions directly transfer membrane potential between cells.
Explain why there is a difference in percent of mass change of the egg in the different sucrose solutions
1— Egg gains mass if solute concentration is lower outside of egg (hypotonic) causing water to move into egg 1— Egg loses mass if solute concentration is higher outside of egg (hypertonic) causing water to move out of egg 1— Water moves from low solute/high water concentration to high solute/low water concentration
Dialysis tubing is permeable to water molecules but not to sucrose. Four dialysis tubes are half filled with 5 percent, 10 percent, 20 percent, and 40 percent sucrose solutions, respectively, and two dialysis tubes are half filled with distilled water. The dialysis tubes are all sealed at both ends, and the initial masses are determined. Five dialysis tubes are placed into beakers containing distilled water, and the sixth dialysis tube, containing distilled water, is placed into a 40 percent sucrose solution. The masses of the dialysis tubes are recorded at 30-minute intervals for 90 minutes, as shown in the table below. The contents of which dialysis tube are initially isotonic to the distilled water in the beaker
5
evaluate the hypothesis that cells shaped like rectangular solids 1 and 2 are better suited for slow metabolism and the long‑term storage of energy‑containing molecules than are cells shaped like rectangular solids 4 and 5.
A cell's surface area to volume ratio limits the cell size. It is proven that cells with smaller sizes are more effective and have long-term storage of energy in comparison to large cells. Cells shaped 1 and 2 have a smaller surface area to volume ratio that supports long‑term storage of energy and is better in slow metabolism than rectangular solids 4 and 5. Hence, because of the smaller surface area to volume ratio 1 and 2 cells has better functions.
Which of the following factors would tend to increase membrane fluidity?
A greater proportion of unsaturated phospholipid
peroxisome
A microbody containing enzymes that transfer hydrogen from various substrates to oxygen, producing and then degrading hydrogen peroxide.
The light reactions of photosynthesis supply the Calvin Cycle with
ATP and NADPH
If an enzyme in solution is saturated with substrate, the most effective way to obtain a faster yield of products is to
Add more of the enzyme
Which chemical group is most likely to be responsible for an organic molecule behaving as a base?
Amino
DESCRIBE the relationship between the dimensions of the rectangular solids and their SA-V ratios
As cells increase in size, the surface area and volume do not usually increase proportionally to length. The greater the diameter of a single-celled organism, the lower the surface area to volume ratio. It is this relationship that restricts the size of a particular cell. Cells must be able to take up and eliminate substances rapidly and efficiently. They must also be able to distribute substances throughout the cell. Most of this distribution occurs by diffusion, which is relatively slow and dependent on random molecular motion.
Which of the following statements is a correct distinction between autotrophs and heterotrophs?
Autotrophs, but not heterotrophs, can nourish themselves beginning with CO2 and other nutrients that are inorganic.
The following questions refer to the following diagram. For each phrase or sentence, select the labeled part to which it is most closely related. Each option may be used once, more than once, or not at all for each group. Site of modification and packaging of proteins and lipids prior to export from the cell
C
Which of the following categories includes all the others in the list?
Carbohydrate
In the late 1980s, sticklebacks from a marine population colonized Loberg Lake, a freshwater lake in Alaska. Starting in 1990, researchers sampled fish from the lake every four years and recorded the armor-plate phenotypes of the male sticklebacks in each sample. The armor-plate phenotypes were categorized as either complete (plates extending from head to tail), partial (plates extending from head to abdomen), or low (a few plates near the head only). The results are shown in the table below. Which of the following descriptions of cell type I and cell type II are most consistent with the data?
Cell Type I Animal cell surrounded by a plasma membrane only Cell Type II Plant cell surrounded by a plasma membrane and a cell wall
Identify the rectangular solid that represents the cell with the smallest amount of plasma membrane per volume of cytoplasm is
Cell four represents the cell with the smallest amount of plasma volume per volume of cytoplasm.
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 mutated aquaporins exhibit moderate turgor pressure and are hypertonic.
Lysosomes
Digests food or breaks down dead cell
nuclear envelope
Double membrane perforated with pores that control the flow of materials in and out of the nucleus.
Identify FOUR organelles that should be present in the eukaryotic organism and describe the function of each organelle. (3)
ER (endoplasmic reticulum) Internal transport or compartmentalization.
What is the most likely pathway taken by a newly synthesize proteins that will be secreted by a cell?
ER-> Golgi-> vesicles that fuse with plasma membrane
EXPLAIN how membranes participate in 3 of the following biological processes (2)
Egg fertilization- Sperm acrosome releases hydrolytic enzymes via exocytosis; Sperm binds to egg's receptors; Fusion of sperm and egg plasma membranes; Fusion of egg and sperm nuclear membranes or nuclei; Separation of fertilization membrane
According to the fluid Mosaic model of membrane structure proteins of the membrane are mostly
Embedded in a lipid bilayer
Which of the following best describes a process that occurs within the Golgi complex?
Enzymatic modification of newly synthesized integral membrane proteins
Catabolism is an anabolism as _________________ is to _______________.
Exergonic; endergonic
endoplasmic reticulum (ER)
Extensive membranous network, continuous with outer nuclear membrane, composed of smooth and rough (ribosome-studded) regions. Provides mechanical support, carries out protein synthesis on membrane-bound ribosomes, and plays a role in intracellular transport.
Cytoskeleton
Forms framework for movement of organelles
smooth endoplasmic reticulum
Functions include detoxification and lipid synthesis.
rough endoplasmic reticulum
Functions to compartmentalize the cell, provides mechanical support, provides site-specific protein synthesis on membrane-bound ribosomes and plays a role in intracellular transport.
The enzyme amylase can break glycosidic linkages between glucose monomers only if the monomers are in the alpha form. Which of the following could amylase break down?
Glycogen, starch, and amylopectin
IDENTIFY 3 macromolecules that are components of the plasma membrane in a eukaryotic cell and DISCUSS structure and function of each. (at least 1 structure & 1 function per macromolecule) (3)
Glycolipid/Glycoprotein: STRUCTURE-carbohydrate (chains) linked to lipid or protein. FUNCTION-cell recognition; Attachment to external molecule or another cell.
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?
Golgi Complex
Based on Table 1, which of the following best explains the difference in water potential between certain solutions and the grapes?
Grape soda and NaClNaCl have a lower water potential because these two solutions caused the grape to lose water.
The immediate energy source that drives ATP synthesis by ATP synthase during oxidative phosphorylation is the
H+ concentration across the membrane holding ATP synthase.
Which of the following best predicts the effect of not having ATP available to supply energy to this process?
H+ ions will stop moving through the protein.
Endosymbiotic theory
How a large cell and an ingested bacteria could easily become dependent on another for survival
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?
In both plant cells and fungal cells, the cell wall surrounds the outside of the cell membrane.
phospholipid
In plasma membrane, hydrophilic phosphate portions face toward aqueous external or internal environments, while hydrophobic fatty acid portions face each other within membrane itself.
Water is constantly diffusing into the cytosol of freshwater single-celled organisms. In order to maintain the proper solute concentrations in the cytosol, contractile vacuoles pump out the excess water. An experimenter placed single-celled organisms into various saline concentrations and recorded the ATP used by the contractile vacuole. The data are shown in the graph. Of the following, which additional investigation can be used to determine when the cells are in an isotonic solution?
Increasing the salinity of the environment a little at a time until the ATPATP usage reaches a minimum
Endosymbiotic evidence
Inner membranes of both organelles have enzymes and transport systems that are homologous to living prokaryotesThe ribosomes of the mitochondria and plastids are extremely similar in size, nucleotide sequence, and sensitivity to certain antibiotics
EXPLAIN how membranes participate in 3 of the following biological processes (3)
Intercellular signaling- Release of chemical signals via exocytosis; Receptors in membrane bind ligands or chemical signals OR chemical signals pass through membrane (neurotransmitters, hormones); Ligand-gated ion channels open/close; Cascade of cellular events, including enzymatic reactions and second messengers (g-proteins, cAMP, Ca2+); Antibodies activate immune function; Describe gap junctions, plasmodesmata (communicating junctions).
Cell connections
Junctions: plasmodesmata and gap junctions
Contains hydrolytic enzymes associated with the intracellular digestion of macromolecules
Lysome
Digestion
Lysosomes, vesicle, vacuoles
glycolipids
Membrane carbohydrates that are covalently bonded to lipids.
glycoproteins
Membrane carbohydrates that are covalently bonded to proteins.
Golgi complex
Membrane-bound structure that consists of a series of flattened membrane sacs. Functions include the correct folding and chemical modification of newly synthesized proteins and packaging (in vesicles) for protein trafficking
vacuole
Membrane-enclosed sac that plays many and differing roles including storage and release of macromolecules and cellular waste products. In plants, a specialized large one serves many functions from storage of pigments or poisonous substances to retention of water for turgor pressure.
lysosomes
Membrane-enclosed sacs that contain hydrolytic enzymes, which are important in intracellular digestion, the recycling of a cell's organic materials, and programmed cell death (apoptosis).
Cyanide bonds to at least one molecule involved in producing ATP. If a cell is exposed to cyanide, most of the cyanide will be found in the
Mitochondria
Energy production
Mitochondria, chloroplasts
The manner in which several different ions and molecules move through a cell membrane is shown in the diagram above. For each ion or molecule, the relative concentration on each side of the membrane is indicated. Which of the following accurately describes one of the movements taking place?
Na+ transport out of the cell requires ATP hydrolysis.
Prokaryotes vs. Eukaryotes
No internal membrane vs. membrane bound organelles
If an enzyme is added to a solution where its substrate and product are in equilibrium, what will occur?
Nothing, the reaction will stay at equilibrium.
Identify FOUR organelles that should be present in the eukaryotic organism and describe the function of each organelle. (1)
Nucleus Contains hereditary information/DNA/chromosomes or is the site of RNA synthesis.
Protein production
Nucleus, DNA, ribosomes, ER, Golgi apparatus, vesicles
We can be sure that a mole of table sugar and a mole of Vitamin C are equal in their
Number of molecules
Centioles
ONLY IN ANIMAL CELLS, Help the cell to divide for mitosis and meiosis
Describe the structure and function of TWO eukaryotic membrane-bound organelles other than the nucleus.
One would be the lysosomes which when you look at it, kind of looks like a bag that has enzymes in it. Its function is to break down the molecules, waste, and food using digestive enzymes. Another one would be chromoplast which has a structure that has the ability to identify two membranes with pigments. Its function is to help store the pigments.
When a substance moves across the plasma membrane along a concentration gradient at a rate faster than would be expected by simple diffusion alone but without the expenditure of metabolic energy, the process is best described as
Osmosis
The final electron acceptor of the electron transport chain thst functions in aerobic oxidative phosphorylation is
Oxygen
If ATP breakdown (hydrolysis) is inhibited, which of the following types of movement across cell membranes is also inhibited?
Passage of a solute against its concentration gradient
Which of the following processes includes all others?
Passive transport
IDENTIFY 3 macromolecules that are components of the plasma membrane in a eukaryotic cell and DISCUSS structure and function of each. (at least 1 structure & 1 function per macromolecule) (2)
Phospholipids OR Lipid with phosphate: STRUCTURE-gylcerol,2 fatty acids,and polar head group w/ phosphate; Lipid bilayer; Hydrophilic/polar head and hydrophobic/nonpolar tails. FUNCTION-selectively permeable; Fluidity; Separates cell from environment,barrier.
The structural level of a protein least affected by a disruption in hydrogen bonding is the
Primary level
homeostasis
Process of maintaining a steady state condition (stable environment) inside a cell or entire organism - "internal balance"
Plasma cell membrane
Protect the cell and regulate the movement of substances through the cell
Which of the following components of the cell membrane is responsible for active transport?
Protein
This group of questions refers to the following groups of biological compounds. (A) Proteins (B) Carbohydrates (C) Nucleic acids (D) Lipids (E) Steroids Synthesized at the ribosome
Proteins
IDENTIFY 3 macromolecules that are components of the plasma membrane in a eukaryotic cell and DISCUSS structure and function of each. (at least 1 structure & 1 function per macromolecule) (1)
Proteins (if using these, you must say these are proteins: integral, peripheral, pump, receptor, transport, tight junction, gap junctions, channel, enzyme): STRUCTURE-Polypeptides, amino acids; Integral, transmembrane, and embedded form channels; Peripheral are on surface; Structure fit to substrate or ligand. FUNCTION-transport; Enzyme or catalysts; Signal transduction; Recognition; Cell junction; Attachment: extracellular matrix-cytoskeleton.
Identify FOUR organelles that should be present in the eukaryotic organism and describe the function of each organelle. (2)
Ribosomes Site of protein synthesis.
vesicle
Small membrane-bound sac that functions in moving products into, out of, and within a cell.
Identify FOUR organelles that should be present in the eukaryotic organism and describe the function of each organelle. (4)
Smooth ER Lipid synthesis or detoxification or transport
Based on the trends shown in the data, EXPLAIN why some rectangular cells include folds or projections in their plasma membranes.
Some rectangular cells include folds or projections in their plasma membrane to increase their SA, which wold also increase the SA-to-V ratio
cell wall
Strong layer of complex carbohydrates around the cell membrane in plants (cellulose), fungi (chitin) and prokaryotes (peptidoglycan).
Many mammals control their body temperature by sweating. Which property of water is most directly responsible for the ability of sweat to lower body temperature?
The absorption of heat by the breaking of hydrogen bonds
Which statement is true of all atoms that are anions?
The atom has more electrons than protons.
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 expand as water moves osmotically into the cells from the blood.
Why are cells so small?
The cellular surface area-to-volume ratio affects a biological system's ability to obtain resources and eliminate waste products. Surface area-to-volume ratio is maximized with small volume.
Paramecia are unicellular protists that have contractile vacuoles to remove excess intracellular water. In an experimental investigation, paramecia were placed in salt solutions of increasing osmolarity. The rate at which the contractile vacuole contracted to pump out excess water was determined and plotted against osmolarity of the solutions, as shown in the graph. Which of the following is the correct explanation for the data?
The contraction rate increases as the osmolarity decreases because the amount of water entering the paramecia by osmosis increases.
plasma membrane
The membrane at the boundary of every cell that acts as a selective barrier, thereby control the exchange of material in and out of cell. Consists of phospholipids, proteins, cholesterol, glycoproteins and glycolipids.
When electrons flow along the electron transport chains of mitochondria, which of the following changes occurs?
The pH of the matrix increases.
Enzymes that break down DNA catalyze the hydrolysis of the covalent bonds that join nucleotides together. What would happen to DNA molecules treated with these enzymes?
The phosphodiester linkages of the polynucleotide backbone would be broken.
Which of the following statements correctly describes any chemical reaction that has reacher equilibrium?
The rates of the forward and reverse reaction are equal.
Why not make cells infinitely small?
Then we couldn't fit the "machinery" inside
Which of the following statements concerning unsaturated fats is true?
They have double bond in the carbon chains of their fatty acids.
Graph on the axes to illustrate water movement into and out of the egg
Title, labels of axes (X must be molar concentration, Y may be change jn mass or % change in mass) 1— Appropriate data selected (molar concentration vs. % change in mass) 1— Axis and data correctly scaled 1— Line graph correctly plotted according to data selected (X and Y axis positions are correct)
transport vesicles
Vesicles in transit from one part of the cell to another.
Which statement best describes the effect on water transport across the cell membrane if the aquaporin in the figure ceases to function?
Water molecules will still be able to move across the cell membrane but at a slower rate.
Which structure is not part of the endomembrane system?
chloroplast
Which metabolic pathway is common to both fermentation and cellular respiration of a glucose molecule?
glycolysis
The bonds that are broken when water vaporizes are
hydrogen bonds between water molecules.
Which structure-function pair is mismatched?
microtubule; muscle contraction
Compared with 31P, the radioactive isotope 32P has
one more neutron.
Which cell would be best for studying lysosomes?
phagocytic white blood cell
Which of the following does not occur during the Calvin cycle?
release of oxygen
Which of the following is present in a prokaryotic cell?
ribosome
ribosomes
small, universal structures (found in all forms of life) comprised of ribosomal RNA (rRNA) and protein. The site of translation of the genetic instructions, according to mRNA sequence, synthesizes proteins. mitochondria
chloroplasts
specialized organelles with double outer membrane found in photosynthetic algae and plants.
Most cells cannot harness heat to perform work because
temperature is usually uniform throughout a cell.
Most CO2 from catabolism is released during
the citric acid cycle.
In the term trace element, the adjective trace means that
the element is required in very small amounts.
The reactivity of an atom arises from
the existence of unpaired electrons in the valence shell.
Which action could produce a carbonyl group?
the replacement of the --OH of a carboxyl group with hydrogen
Organic chemistry is currently defined as
the study of carbon compounds
Some bacteria are metabolically active in hot springs because
their enzymes have high optimal temperatures.