Answer:
To ensure their survival by reproducing
The Opponent-Process theory of color vision holds that we perceive colors because of pairs the receptors that make antagonistic responses. <span />
It’s 4 because meiosis is the process that happens first, it is the production of sex cells which are gametes. These gametes which are egg cells and sperm cells meet during sexual inter coarse, fertilization occurs. This fertilization causes the formation of the zygote which then converts to embryo.
Hope this helps:)
Answer:
The Miller and Urey experiment is a well-known classic experiment in which hypothetical conditions of the early Earth's evolution were simulated to test the possibility of chemical evolution. In fact, this was an experimental test of the hypothesis previously expressed by Alexander Oparin and John Haldane that the conditions that existed on primitive Earth promoted chemical reactions that could lead to the synthesis of organic molecules from inorganic ones. It was held in 1953 by Stanley Miller and Harold Urey. The apparatus designed for the experiment included a mixture of gases corresponding to the notion of the composition of the atmosphere of the early Earth in the 1950s, and electric discharges passing through it (simulating lightning strikes on the ground). The Miller and Urey experiment is considered one of the most important experiments in the study of the origin of life on Earth.
b
I am not that sure but I think endocrine cell don't contain blood vessels