Animal cells have plasma membrane while plant cells have
cell wall and cell membrane.
A plant cell has 1 large vacuole while an animal cell has
more than 1 vacuole which is smaller compared to the vacuoles of a plant cell.
The vacuole of a plant cell is hypertonic because it takes up to 90% of the
cells volume.
A plant cell has chlorophyll or chloroplasts (which gives
colors to plants), animal cells does not have chloroplasts.
Cell division is also called mitosis (this term is used for
both animal and plant cells, no difference on that). For plant cells,
centrifugal division occurs, its starts in the middle going outwards creating
the cell plate. For animal cells, division is centripetal that it comes from
the outside going toward the center and that is called the cleavage furrow.
Anopheles is a genus of mosquito first described and named by J. W. Meigen in 1818. About 460 species are recognised; while over 100 can transmit human malaria, only 30–40 commonly transmit parasites of the genus Plasmodium, which cause malaria in humans in endemic areas.
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.
For the last question it's either C or D.
Answer: The correct option is E ( Intermediate filaments are unpolarized).
Explanation:
Intermediate Filaments are usually associated with cells that can withstand mechanical stress which includes claws of animals, hair and makes up the dead remnants of the epidermal cell of the skin. Therefore without the supporting network of intermediate filaments, an epithelium remains intact but the cells are prone to damage by abrasive forces.
Intermediate filaments are so named because they are thicker than actin filaments and thinner than microtubules or muscle myosin filaments
The properties or characteristics of an intermediate filaments that explains the lack of motor proteins is as a result of its subunits which are elongated, not globular and are associated in an anti-polar manner. Therefore, the overall filament has no polarity, and therefore no motor proteins move along intermediate filaments