Answer:
The correct answer is: d. REs activity is best preserved by freezing the RE and thawing it out for brief periods of time as needed.
Explanation:
- Restriction enzymes can be defined as endonucleases that can recognize specific nucleotide sequence in a DNA (Deoxyribonucleic acid) sequence and cause breakage of phosphodiester bond in the DNA at the target site. Hence, it has the capacity of cleaving a DNA sequence.
- These are made up of proteins which are required to be present in the accurately folded conformation in order to function.
- Any form of alteration in the three-dimensional structure of the protein induced due to physical, chemical, mechanical or physiological factors can cause denaturation of the protein which in turn can render the protein non-functional.
- Freezing of restriction enzymes (REs) directly without the use of glycerol will cause the movement of water molecules within the proteins as well layering of water molecules on the protein surface.
- At low temperature these water molecules change to ice crystals which can alter the conformation of the protein or can cause breakage of peptide bonds in the proteins by physical force.
- This can cause the protein to get denatured and hence non-functional.
- Hence, it is never advisable to preserve REs by freezing directly without glycerol.
- Glycerol forms a layer around the protein molecules and prevents the protein molecules from coming into direct contact with the water molecules and hence prevents protein denaturation.
Answer:
Tendons may also attach muscles to structures such as the eyeball. A tendon serves to move the bone or structure. A ligament is a fibrous connective tissue which attaches bone to bone, and usually serves to hold structures together and keep them stable.
Answer:
Independent Variable:
temperature
dependent variable:
chirps
Hypothesis:
the lower the temperatures the less chirps
constants:
temperature or food and water
repeated trails:
success and failure
control:the experiment
Answer:
It should be A
Explanation:
The Golgi apparatus is made up of stacks of membrane sacs. Transport vesicles, carrying proteins from the endoplasmic reticulum, enter the Golgi apparatus to be modified and stored. Eventually, these proteins are sent on to their final destinations inside or outside of the cell.
<span>Covered by the two cerebral hemispheres, the diencephalon is
the structure of the central nervous system that surrounds the third ventricle.
It is composed of several other structures. The most important of them are the
Thalamus, which plays a very important role in movements and emotions; and the
Hypothalamus, which provides functions including thermoregulation, appetite and
regulation of the sleep-wake cycle.</span>
