<span>The tissue is a group of structurally and functionally similar cells and their extracellular matrix. Grouping of those similar cells enables them to carry out a specific function. In the hierarchy of structural organisation tissue is level between cells and a complete organ. Functional grouping together of multiple tissues forms an organ.</span>
<span>The person can prepare by eating the right food, exercise, hydration of self and condition oneself for the incoming adventure like extreme. And also the human body systems respond to changes in the external environment, the nervous system and hormones enable us to respond to external changes. </span>
Answer:
1. It was a control variable
2. Type of insulation
3. Temperature
4. Plastic lids <em>or </em>Water <em>or </em>Half Full <em>or </em>Direct Sunlight
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.
