exam 1 prep Flashcards
(62 cards)
Which reaction is likely coupled with hydrolysis of ATP?
endergonic reactions
Which of the following is true of all eukaryotes (check all that apply)?
- Their cells contain organelles
- Their cells have plasma membranes
- Their cells lack cell walls
- They are multicellular (ie. composed of >1 cell)
- Their cells’ nuclei contain DNA
- Their cells contain organelles
- Their cells have plasma membranes
- Their cells’ nuclei contain DNA
Which of the following is an organelle that functions to break down sugars to generate a molecule that serves as a source of energy for many biological processes?
- Mitochondria
- Nucleus
- Chloroplasts
- Lysosome
- Smooth endoplasmic reticulum
Mitochondria
Which of the following would NOT be visible using a light microscope?
- Ribosomes
- Nucleus
- Mitochondria
- A whole eukaryotic cell
- A whole bacterial cell
Ribosomes
If the plasma membrane of a cell became dysfunctional, what would you predict to be an immediate consequence for the cell?
- Proteins that need to leave the cell wouldn’t be made
- Lipids would not be broken down for reuse
- Toxic substances could enter the cell
- ATP synthesis would be disrupted
- DNA would not be replicated
Toxic substances could enter the cell
Animal cells have mitochondria while plant cells have chloroplasts instead of mitochondria.
- True
- False
False
Approximately how big, in millimeters, is the Escherichia coli cell shown in Figure 1a in its shortest dimension (ie. focusing on its main body, not including the structures that extend off the main body)?
Figure 1a = 0.5um
- 5
- 0.005
- 0.0005
- 50
- 500
- 0.05
0.0005
Relative to the bacterium, approximately how many fold bigger is the human corneal epithelial cell (from the cornea of an eye, shown in Figure 1b) in its’ shortest dimensions?
Figure 1a = 0.5 um
Figure 1b = 5 um
~40x ~1/10 ~500x ~1/500x ~10x ~1/40
~40x
Which of the following bonds do NOT result from an attraction between opposing partial or full charges (check all that apply)?
- hydrogen bonds
- ionic bonds
- polar bonds
- hydrophobic interactions
- nonpolar bonds
- polar bonds
- hydrophobic interactions
- nonpolar bonds
consider the reaction A B where Keq for A->B = 0.02 and initial concentrations are A = 1000 uM and B = 10 uM.
Given enough time, which of the following will be the outcome?
- The final concentration of A will be equal to B
- The concentrations of A and B will not change
- It is impossible to tell from the information given
- More A will be generated
- More B will be generated
More B will be generated
consider the reaction A B where Keq for A->B = 0.02 and initial concentrations are A = 1000 uM and B = 10 uM.
What is the initial ΔG of the A->B reaction?
0.01 It is impossible to tell from the information given 0 <0 >0
<0
A(n) _________ reaction requires a sustained input of energy. In contrast, sustained energy is not required for a(n) ________ reaction to proceed.
endergonic
spontaneous
What type of reaction with the ΔG below could be suitably coupled to the reaction A + B -> C, ΔG = 9.6 kcal/mole in order to increase the rate of generating C.
ΔG = -11 kcal/mole ΔG = -6.7 kcal/mole ΔG = -9.5 kcal/mole ΔG = 10.5 kcal/mole ΔG = 9.7 kcal/mole
ΔG = -11 kcal/mole
Which of the following statements best describes the primary structure of a protein?
- The linear sequence of amino acids in a polypeptide chain
- The 3-D conformation of a multisubunit protein
- The 3-D conformation of an entire polypeptide chain
- The local structure of a polypeptide chain stabilized only by hydrogen bonds
- The assembly of multiple polypeptide subunits
The linear sequence of amino acids in a polypeptide chain
Though the amino acids phenylalanine and tyrosine are very similar in size and shape, tyrosine can engage in noncovalent interactions that are not possible for phenylalanine. What would most likely underlie these tyrosine-dependent interactions that phenylalanine can’t support?
- hydrophobic interactions
- ionic bonds
- hydrogen bonds
- polar bonds
- polar bonds and hydrogen bonds
ionic bonds
Assume that the circled atoms/chemical groups in glycine and alanine shown below in Figure 4 would still be present when these amino acids are incorporated into the silk protein referenced above in Figure 3. Which of them could be engaged in the bonds/interactions that stabilize individual beta sheets in silk (check all that apply)?
- Hydrogen attached to the Nitrogen
- Oxygen double bonded to the non-centered Carbon
In the silk proteins referenced above in Figure 3, the R groups of glycine and alanine are engaged in the bonds/interactions that stabilize the packing of multiple beta sheets together in stacks in a manner that excludes water.
If you wished to design silk fibers that are less stable in the presence of water (ie. can’t exclude water completely) what amino acid replacements for glycine and alanine would you propose? Include in your answer the types of bonds/interactions that glycine and alanine R groups likely form in silk and why your replacements would create instability for silk in the presence of water.
Since glycine and alanine R groups are likely formed due to van der Waals interactions, the hydrophobic interactions would undergo in the presence of water which means a replacement could be any polar or charged amino acid. The hydrophilic replacements in the new R group would create instability for silk in the presence of water because they can interact with water due to their partial or full charges.
The enzymatic activity of kinases catalyzes:
- The hydrolysis of ATP
- The removal of a phosphate group from a molecule
- The hydrolysis of GTP
- The transfer of a phosphate group from GTP to a target molecule
- The transfer of a phosphate group from ATP to a target molecule
The transfer of a phosphate group from ATP to a target molecule
An allosteric regulator can increase the catalytic activity of an enzyme by binding to a site far from the enzyme’s active site.
True
False
True
The theme of structure informing function is something that runs throughout biology. In three (3) sentences or less, please give one example of this that you have learned about in Biology 205 so far and provide the rationale for your choice.
- presence of high level of certain organelles for specialized cell function, like highly numbers of mitochondria for muscle cell function in cytoskeletal contractions and movements
- protein structure informing specificity for particular binding partners, such as enzymes for their substrates
- hydrophobic inside of membranes prevents many substances from easily entering the cell, enabling the function of membranes as barriers.
Since kinases transfer phosphate groups from ATP or GTP. Kinases only transfer phosphate groups from ATP
True
False
True
Describe key properties that something must have to be considered alive.
movement, breathing or respiration, excretion, growth, sensitivity and reproduction…
Cellular organization, the ability to reproduce, growth & development, energy use, homeostasis, response to their environment, and the ability to adapt
What is a cell
Cells are the basic building blocks of all living things. A cell is a mass of cytoplasm that is bound externally by a cell membrane….
Unicellular
living things made up of a single cell
