A. There were animals 3 billion years ago; they just weren't fossilized. B. Animals are warm-blooded; the ocean was too cold for animals.
What do you mean by responsible? Do you want to know the genetics behind it, what the surface markers do, or why they are metically important? I think I can help.
The answer is the option A. removing plants from hillsides eliminates the root structures that anchor soil. Indeed the roots of trees, further to anchor the tress to the floor, serve as a net to which the soil attaches preventing the soil of been washed and removed by rainstorms
Photosynthesis is a process used by plants and other organisms to convert light energy into chemical chemical energy that can later be released to fuel the organisms activities.
Fluid filled sacs in the knee are specifically called Bursa or Bursae. Bursae is plural for Bursa.
A bursa is a closed fluid filled sac that function as a gliding surface to reduce friction between tissues of the body. Knee bursitis occurs when there is irritation or inflammation in one one of the knee bursa. The procedure of removing fluid-filled sac is called bursectomy. When the bursa become infected with bacteria, this condition is called septic bursitis.
