Answer:
1. Skin Creams
Explanation:
An independent variable is the only variable that is changed while the rest is kept the same. In this setup, the doctor is using different creams on the same patient with the same skin condition so the independent variable is the skin cream and not the skin condition.
Answer:
Human, nervous system, nerve tissue, neurons.
Explanation:
The organism is the biggest, in this case is a human, a human is composed of systems, and then organ tissue, and organ tissue is made out of cells.
Answer:
Testing positive for HIV means a high chance of death and a good chance of lower reproduction rates. But some people are immune to HIV, which makes them more evolutionarily fit, likely to live longer, likely to reproduce more, which would increase the frequency of the immune allele in the population. Over time, this increase in frequency of the gene that causes immunity could spread across the human race and cause it to evolve.
The earliest forms would be plants and other life like that, and current day would be mostly humans and animals and a lot of plants are disappearing
That organelle is the mitochondria