Answer: Cell membrane is layer which is present in all living cells. It is present under the cell wall but in some cases such as plant cells.
Explanation: It is composed of lipid bilayer and proteins embedded in it. Phospholipids, glycolipids and sterols is the composition. Its function is to protect the cell from extracellular environment. It is semipermeable membrane that js allow only selected molecules to pass.
<span> Enzymes are usually proteins but some also contain nucleic acids (RNA in particular) and the list of chemical reactions that are catalyzed by RNA has been expanding. So the answer is proteins.</span>
Answer:
Real dinosaurs can not be studied because they died out many years ago. so this is how we are learning about the past
Explanation:
Explanation:
Looking at the Ecological concept of Modern Ecology
we have
Atmosphere, Lithosphere, Biosphere, Niche, Environment, Habitat, Population, Ecosystem and Biotic community
Hydrosphere and Geosphere are not part
so Atmosphere is the correct answer
Borders are still guarded zealously and fought for - via wars when required and when not required in equal measure. I see nations fighting
over water that preciously scarce resource of the future. I see that terrorists still abound - the Osama Bin Laden types still roam the Earth terrorizing countries and peoples with newer weapons and newer methods of instilling terror. I see that the United States is no longer the sole superpower of the world -- the most powerful country on Earth. I see the most powerful countries dominating the world as being China, India, Brazil and Russia in that order. I see that China and India have become the equivalent of the US and the erstwhile Soviet Union - fighting another Cold War between them and competing for resources and influence around the world.