TLS Online TPP Program

#Question id: 23629


Mechanical shearing is often the preferred method of fragmenting genomic DNA when constructing a genomic DNA library. Why would this method be preferred over complete digestion with restriction enzymes?

#Unit 14. Methods in Biology
  1. Enzymes might produce fragments that are too small or too large to be cloned.
  2. Enzyme cleavage can interrupt important gene sequences, in which case not all genes may be represented in the library.
  3. Shearing ensures the library contains overlapping fragments of DNA, which makes it possible to perform a chromosome walk.
  4. All of the above
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TLS Online TPP Program

#Question id: 12060

#Unit 7. System Physiology – Animal

 Eating a meal leads to a large increase in gastric acid secretion that peaks within about 5 min and returns to normal about 4 hr after a meal is taken. How long after a meal does the pH of the gastric contents reach its lowest level (in hours)?

TLS Online TPP Program

#Question id: 12061

#Unit 7. System Physiology – Animal

Cystic fibrosis (CF) is an inherited disorder of the exocrine glands, affecting children and young people. Mucus in the exocrine glands becomes thick and sticky and eventually blocks the ducts of these glands (especially in the pancreas, lungs, and liver), forming cysts. A primary disruption in the transfer of which ion across cell membranes occurs in CF leading to decreased secretion of fluid?

TLS Online TPP Program

#Question id: 12062

#Unit 7. System Physiology – Animal

Mass movements are often stimulated after a meal by distention of the stomach (gastrocolic reflex) and distention of the duodenum (duodenocolic reflex). Mass movements often lead to which of the following?

TLS Online TPP Program

#Question id: 12068

#Unit 7. System Physiology – Animal

Prolonged changes in neuronal activity are usually achieved through the activation of

TLS Online TPP Program

#Question id: 12069

#Unit 7. System Physiology – Animal

Post-tetanic facilitation is thought to be the result of

TLS Online TPP Program

#Question id: 12070

#Unit 7. System Physiology – Animal

A 26-year-old man develops glomerulonephritis, and his GFR decreases by 50% and remains at that level. For which of the following substances would you expect to find the greatest increase in plasma concentration?