Answer:
In allosteric inhibition, a regulatory molecule binds to a location other than the active site, resulting in a change in enzyme shape that allows the active site to bind substrate.
Explanation:
Allosteric regulation of an enzyme can be positive or negative, but it always involves effector molecules that bind to non-active site of the enzyme and change its conformation. That site of binding is called allosteric or regulatory site. If the enzyme activity is enhanced effector molecule is called allosteric activator but if the activity is decreased effector molecules are allosteric inhibitors.
Answer:
When a cell was examined under a microscope, it was found that it did not have a cell wall . It has a cell membrane which shows the viewed cell under microscope is an animal cell
Explanation:
Only plant cell has cell wall which gives rigidity and shape to the cell unlike animal cell which has a cell membrane. The cell would comprise of chloroplast, nucleus, golgi apparatus, mitochondria among others
Answer:
D. Psychrophile
Explanation:
Psychrophiles or cryophiles are a type of extremophiles i.e. they live in extreme environment. They grow well in low temperatures ranging from -20 to +10 degree Celsius.
Here, the bacteria was incubated at different temperatures. It did not show growth at standard incubation temperature of 37°C which indicates that it might be an extremophile preferring either very hot or very cold environment. But it also did not show growth at 50°C which means that it does not survive well at high temperature.
Lab bench top has generally colder surface compared to the surrounding environment and a little growth was observed there which indicates that this bacteria might require cold temperature for growth. The result was finally confirmed with abundant growth observed inside refrigerator which is only possible if it is a psychrophile.
Answer: The base pair rule for RNA is that adenine pairs with uracil, thymine pairs with adenine and cytosine pairs with guanine.
Explanation: RNA contains adenine, uracil, cytosine and guanine while DNA contains adenine, thymine, cytosine and guanine. Thymine is not found in RNA while uracil is not found in DNA. In RNA base pairing, Watson and Crick proposed a rule that wherever adenine is found in DNA, Uracil occurs in the complementary RNA strand, wherever thymine is found in the DNA strand, adenine is found in the complementary RNA strand and wherever guanine occurs in the DNA strand, cytosine is found in the complementary RNA strand.
