The plant growing up a brick wall would be both exhibiting and gravitropism, hope this helps
Answer: If we kill all the organisms in one trophic level, then transfer of energy as well as matter to next higher level will stop. It will lead to over- population at one particular level causing amongst the individuals. This would seriously disturb the food chain and can cause the collapse of an ecosystem even.
Red blood cells and lots of blood clots due to plasma and platelets
To protect them from ultraviolet rays from the sun.