One hypothesis that is in the scientific community which relates to the origin of the building blocks for life is that they were formed when lightning struck water.
Answer:
d. dynamic receptor proteins
Explanation:
In the skin there are several receptor cells that can pick up various stimuli such as temperature, pressure and pain. They can be classified into mechanoreceptor, thermoreceptor and pain receptor cells. When we are dealing with mechanical stimuli like pressure, mechanoreceptors respond to stimuli by sending the signal to the brain.
Light touches on the skin are received by nerve endings called Meissner corpuscles and Merkel discs. Already more intense pressures (such as a handshake) are received by receptors called Pacini corpuscles.
Answer:
C
Explanation:
oxygen levels are high in the summer while the sun is shining and plants are photosynthesizing but they can drop in the winter
If it were single celled, then it would need some form of protection so the answer would be C. an outer covering
