1) Pemphigus vulgaris is an autoimmune disorder in humans in which antibodies are produced against the cadherins of desmosomes. The blistering of the skin and mucous membranes characteristic of this disorder is probably a result of _____.
a) a decrease in flexibility of the cell membrane
b) an inadequate number of G-protein receptors
c) inadequate production of cytoskeletal proteins
d) a loss in cell-cell adhesion
2) What function does kinesin have in cells ?
a) Kinesin associates with actin for muscle movements.
b) Kinesin helps flagella and cilia to move
c) Kinesin escorts carries proteins with NLS into the nucleus
d) Kinesin carries vesicles and organelles along micotubule tracks.
3) The CO2 from the breakdown of glucose is released during;
a) glycolysis and acetyl CoA formation
b) acetyl CoA formation and the citric acid cycle
c) glycolysis and electron transport chain
d) fermentation and glycolysis
4) Why are there several types of pigments arranged into antenna complex in photosystems?
a) To enable the plant to absorb green light for photosynthesis
b) To facilitate the absorption of carbon dioxide by a larger surface area
c) To increase the number of components in the electron transport chain that prodces ATP
d) To increase the amount and range of wavelengths of light absorbed by the plant
5) The primers added by primase enzyme during DNA replication are _____.
a) proteins that bind to single-stranded DNA
b) short DNA sequences
c) short amino acid sequences (peptides)
d) short RNA sequences
6) Which of the following is an example for 'a protein binding to DNA'?
a) G-protein binds GTP
b) a signal binds to a receptor
c) cAMP binds to the CAP protein
d) repressor binds to the operator in lac operon
7) Which of the following types of mutation would convert a proto-oncogene into an oncogene?
a) a mutation that blocks transcription of the proto-oncogene
b) a mutation that greatly increases the amount of the proto-oncogene protein
c) a mutation that creates an unstable proto-oncogene mRNA
d) a deletion of most of the proto-oncogene coding sequence
8) Which of the following chemical bonds have the lowest energy stored?
a) C-H bonds
b) C-O bonds
c) C-C bonds
d) All of these bonds have equivalent amount of energy.
9) If you shake pohospholipids with a hydrophobic solvent (instead of with water), they will still form bilayers. The heads of phospholipid molecules in this bilayer would be pointed towards;
a) exterior of the membrane
b) interior of the membrane
c) both interior and exterior of the membrane, randomly