Questions at end of lectures Flashcards
Describe the characteristics of life as defined by biologists. What signs of life are present in a fossil?
a
Describe the basic tenets of natural selection. What is wrong with the following statement? A seal’s body shape changes so that it is very hydrodynamic to swim in the ocean.
a
How does the term population relate to the term community? Cell to organism?
a
What is the role of the control group in hypothesis testing?
a
Describe the commonalities in biological knowledge generated by Indigenous people and academic biologists.
a
How does the polarity of water lead to hydrogen bonding? What substances will be hydrophobic?
a
Describe the different properties of the various states of water. How does this relate to evaporative cooling, freezing?
a
How is pH calculated? How do the relative concentrations of hydrogen and hydroxide ions of solutions of different pHs differ?
a
Describe some ways in which the physical properties of water can affect biological systems.
a
If the pH of a solution is decreased from 9 to 7, it means that the ___ .
a) concentration of OH- has increased two fold compared to what it was at pH 9.
b) concentration of H+ has decreased to one tenth of what it was at pH 9.
c) concentration of H+ has increased two fold compared to what it was at pH 9.
d) concentration of OH- has decreased to one hundredth compared to what it was at pH 9.
e) concentration of H+ has increased 100 fold compared to what it was at pH 9 and concentration of OH- has decreased to one hundredth of what it was at pH 9.
e)
What are the acids and bases? Describe some examples of the biological relevance of pH.
a
What are the buffers? What is the importance of buffers in biological systems?
a
Describe variety of different configurations that can be formed with carbon as a backbone for molecules.
a
What are isomers? Describe the different types of isomers. Why are they biologically meaningful?
a
Write the structure of the functional groups described in this lecture and describe the associated properties.
a
Describe the difference in the biological vs colloquial meaning of organic.
a
Which is a basic functional group that can accept H+ and become positively charged?
a) --OH
b) O
||
--C--
c) O
||
--C--O--H
d) --NH2
e) --SHd) amino group, because it can ionize
Describe the reactions involved in polymerization and depolymerization.
a
Describe the general structure of an amino acid. In what ways do the 20 major amino acids differ? Be able to classify the amino acids based on those differences.
a
Describe how polypeptides form, including the functional groups involved in formation of the bond.
a
Describe the four levels of protein 3D structure and how they are maintained. What is the importance of these 3D structures?
a
Describe with examples, the factors that can lead to malfunction of a protein and how can protein misfolding can be corrected. Use the following in your answer: gene, denaturation, chaperonin, sickle cell anemia.
a
What makes one amino acid different from another?
a) different side chains (R groups) attached to a carboxyl carbon
b) different side chains (R groups) attached to the amino groups
c) different side chains (R groups) attached to an alpha carbon
d) different structural and optical isomers
e) different asymmetric carbons
c)
Describe the general structure of monosaccharides and polysaccharides. Describe the structural variation in monosaccharides (linear).
a
Describe how glucose forms a ring in solution. What isomers are possible?
a
Describe the structures and functions of starch, glycogen, cellulose, and chitin.
a
Describe how starch and cellulose are formed. Why can humans digest starch but not cellulose?
a
Describe the components of a nucleoside and nucleotide.
a
Describe the arrangement of sugars, nitrogenous bases and phosphate in a polynucleotide in general and in DNA specifically.
a
The D enantiomer of glucose is found in living organisms. Chemists can make an L enantiomer of glucose but it cannot be used by the enzyme hexokinase. What is the best explanation for this?
a) L glucose has a different number of atoms than the other enantiomer.
b) L glucose is an open ring and the other isoform is a closed ring.
c) L glucose is a pentose sugar and the other isomer is a hexose sugar.
d) L glucose is a polymer and D glucose is a monomer.
e) The enzyme has evolved to fit the 3D structure of the other enantiomer.
e)
Describe the structure of a fatty acid and the ways in which different fatty acids and triacylglycerols can differ from one another.
a
Describe the structure and bonds involved in the formation of triacylglycerols and phospholipids.
a
Describe the interactions of phospholipids with water.
a
Describe the structure and biological importance of cholesterol and other sterols.
a
What are the necessary components of all cells? What is their function?
a
Describe the basic structure of a plasma membrane? What physical factors are involved in membrane structure?
a
Which of the following statements concerning saturated fats is false?
a) They are more common in animals and than plants.
b) They have multiple double bonds in the carbon chains of their fatty acids.
c) They generally solidify at room temperature.
d) They contain more hydrogen than unsaturated fats having the same number of carbon atoms.
e) They are one of several factors that contribute to atherosclerosis.
b)
Describe the fluid mosaic model of cell membranes with respect to the phospholipids and proteins.
a
Why are flip flops of phospholipids within the membrane seldom?
a
What is the effect of unsaturation on membrane fluidity? How do some organisms respond to maintain fluidity in the face of temperature changes?
a
What factors constrain cell size?
a
Describe the differences and similarities between prokaryotic and eukaryotic cells.
a
Discuss how the following relate to each other in regard to history of life on earth: first cells, eukaryotic cells, photosynthesis, oxygen revolution, multicellular organism.
a
Month % saturated fatty acids January 59 March 58 May 42 August 25 November 49
a) this invertebrate lives on land
b) the habitat of this invertebrate is coldest in August
c) the proportion of unsaturated fatty acids is highest in January
d) the gill membrane lipids of this invertebrate are most fluid in January
e) the gill membrane lipids of this invertebrate are least fluid in August
b) % of saturated fatty acids in the gills of an invertebrate that exhibits homeoviscous adaptation to temperature change
Compare a nucleoid and a nucleus. Describe the structure of a nucleus.
a
Describe the structure, function, and relationships among the following: endoplasmic reticulum, golgi, smooth and rough ribosomes, plasma membrane proteins.
a
Trace the path of a protein from synthesis to deposition in the plasma membrane.
a
Distinguish between autophagy and phagocytosis. Describe the role of lysosomes in autophagy and phagocytosis.
a
Describe the structure of a mitochondrion.
a
Which of the following is not synthesized in the rough ER?
a) endoplasmic reticulum proteins
b) extracellular matrix proteins
c) secreted proteins
d) mitochondrial proteins
e) plasma membrane proteins
d)
Describe the internal structure of mitochondria and chloroplasts.
a
Describe the theory regarding the evolution of the first photosynthetic eukaryotes. What is the evidence for this?
a
What is the cytoskeleton? What are the functions of the various types of cytoskeletal fibers?
a
Describe the arrangement of microtubules in a eukaryotic cilium. What is the difference between the extracellular portion and the basal body?
a
Describe and compare the extracellular structures of bacteria, plants, and animals.
a
How is the first endoplasmic reticulum thought to have formed?
a) from endosymbiosis of a photosynthetic prokaryote
b) from endosymbiosis of a prokaryote with aerobic metabolism
c) fusion of a mitochondria with the nuclear envelope
d) fusion of golgi membranes with the nuclear envelope
e) from an infolding of the plasma membrane in a prokaryote
e)
Describe the similarities and differences among simple diffusion, facilitated diffusion, and active transport using the words permeability, ATP, concentration gradient and protein.
a
Describe osmosis using the correct terminology associated with tonicity.
a
Describe the response of animal, plant and Paramecium to isotonic, hypotonic, and hypertonic solutions.
a
Describe how ATP is used in active transport using the example of the sodium potassium pump, and including the stages of the pumps action.
a
What is a membrane potential? Describe how active transport can create a membrane potential. How does this relate to “electrochemical gradients.”
a
A solute can enter the cell without the use of ATP but not if a certain transmembrane protein is blocked. What does this likely indicate?
a) The solute is non-polar and is in lower concentration outside the cell.
b) The solute is polar and is in higher concentration outside the cell.
c) The solute is a hydrocarbon and is in higher concentration outside the cell.
d) The solute can only enter the cell via active transport.
e) The transport protein is the sodium potassium pump.
b)
Why is an energy input necessary for plant cells to accumulate sucrose? What is the source of energy and how is it involved in the process?
a
Describe the ways in which cells bring bulk food items/large molecules into the cell against a gradient.
a
Describe the catalytic cycle of an enzyme using the proper terminology.
a
What is enzyme activity? Describe the factors that can affect enzyme activity, including allosteric factors.
a
Describe how enzymes can evolve to adapt to changing environmental conditions.
a
Which of the following best describes how ATP is used to accumulate sucrose in a plant cell by cotransport?
a) ATP phosphorylates the sucrose transporter, providing the energy for transport of sucrose down its gradient.
b) ATP is used by a proton pump to move hydrogen ions and sucrose ions down their gradient together
c) ADP phosphorylates the sucrose transporter, allowing sucrose to be moved against its gradient
d) the proton pump uses ATP to create a proton gradient into the cell which is used by the sucrose transporter to move sucrose against its gradient
e) the sucrose transporter uses the potential energy of extracellular sucrose to move it against its concentration gradient.
d)
Describe how allosteric inhibition is involved in shutting off a metabolic pathway. Why might this be necessary?
a
Describe the sucrose proton transporter described in the last lecture in terms of the free energy dynamics.
a
A reaction has a delta G of =10 kcal/mol. How would you classify this reaction? Do the products or the reactants have a higher free energy? Can the hydrolysis of one ATP molecule power this reaction? Why or why not?
a
Describe the overall redox reaction of the catabolism of glucose.
a
Write the reactions for the oxidation of NADH and the reduction of NAD+. What happens to the hydrogens and electrons in each case?
a
ATP hydrolysis has a delta G of -7.4 kcal/mol. Which of the following is true regarding ATP hydrolysis?
a) It can provide the necessary energy for a reaction with a delta G of +8 kcal/mol.
b) It can provide the necessary energy for a reaction with a delta G of -2 kcal/mol.
c) It can provide the necessary energy for a reaction with a delta G of +3.4 kcal/mol.
d) It requires an input of 7.4kcal/mol energy to occur.
e) It is endergonic.
c)
What is the relationship between glucose, NAD+, NADH and oxygen in cellular respiration?
a
What is the investment stage in relation to glycolysis?
a
Name the overall reactants and products of glycolysis and the citric acid cycle.
a
Examine the stages of glycolysis and the citric acid cycle and identify the redox reactions, substrate level phosphorylations and isomerizations.
a
Compare the locations of glycolysis and the citric acid cycle in eukaryotes and prokaryotes.
a
A cell biologist prepares some isolated mitochondria. She measures the rate of activity an enzyme of the Krebs cycle, citrate synthase, by following the appearance of some of the products of the reaction with a radio-labelled substrate that she will add. Since there are no substrates from the cytosol in her isolated mitochondrial preparation, which of the following will she label and provide to the mitochondria?
a) FADH2
b) ATP
c) Pyruvate
d) Glucose
e) NADH
c)
