What does an electrocardiogram (ECG) measure? How does it work?
What will be an ideal response?
Ans: An ECG records the electrical activity of the heart. It is measured by placing electrodes at locations around the heart. Because different parts of the heart contract at different times (e.g. the atria contract before the ventricles), potential differences are created between these regions which are detected by the electrodes.
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Programmed cell death is known as ____.
A. autophagy B. mitosis C. apoptosis D. meiosis E. cell genesis
Two technologies that sped progress of the human genome project in 1991 were
A) recombinant DNA technology and PCR. B) amniocentesis and chorionic villus sampling. C) the invention of the Internet and personal computers. D) expressed sequence tags and microarrays.
Which of the following would not be a valid reason to use PCR?
(A) Help in analyzing DNA of ancient remains of fossilized wholly mammoth (B) Help in determining the DNA of a hair sample found at a crime scene (C) Help in analyzing the genome of a virus (D) Help transferring DNA from a plasmid containing GFP into E. coli
Imagine an artificial cell made with a selectively permeable membrane that allows water to pass through but does not allow sugar to pass
If the artificial cell contains a 1% sugar solution and then you place the cell in a 2% sugar solution, what happens? A) There is no movement of water. B) Water leaves the cell because the solution is hypertonic to the cell. C) Sugar diffuses in and water diffuses out until equilibrium is reached. D) Water enters the cell because the solution is hypotonic to the cell.