Polar and Ionic compounds
Answer:
The correct answer is d all of the above
Explanation:
There are many reasons behind increasing the concentration of atmospheric carbon dioxide such as
1 Burning of fossil fuels such as coal,petroleum increases the level of atmospheric carbon dioxide.
2 Increase in Argiculture also increases the level of green house gases such as CO2.
3 Clearing of lands for increasing population and agriculture by cutting down trees also adversely effect the normal 02:CO2 ratio in the atmosphere.
Answer: PCR allows us to target and amplify one specific segment of DNA that is a few hundred base pairs in length out a complete genome of over 3 billion base pairs.
Explanation:
Lipid bilayer model was proposed for its structure but it was modified and new structure is according to fluid mosaic model. Plasma membrane is selectively permible as it selects small molecules like lipid etc (composition is also of lipid and as solubility principle like dissolve like) so large and charged molecules like plasma and ion can't pass through it. Lipid are in form of layer so at the chain when ever other phosphate group attach the place conjugate molecule (phospholipid ) formed