In an area with an ecological gradient, the relative abundance of plants and animals changes according to
a. human population
b. elevation
c. biome type
d. number of species

What are some possible short and long term medical concerns for crew members on longer space exploration trips

The unique structure of the neuron is dedicated to the efficient and rapid transmission of neural signals. the relationship between neurons, the spinal cord, and the brain constitutes an elaborate communication system throughout the human body. all but one of the functions listed below are a result of this interaction.

Is there any solid scientific evidence that humans have been cloned?