Answer:
There are two possible answers: Deep-sea vents provided the energy needed for the first organic compounds to form OR self-replicating RNA molecules passed on genetic information.
Explanation:
The reason for the first answer is due to the hypothesis that indicates that life (organic molecules) arose from inorganic molecules synthesized from the amino acids in those energy vents. This is called the metabolism first hypothesis. The Miller-Urey Experiment provided evidence that organisms could rise from inorganic molecules (they simulated under the conditions you would see on early Earth). The second hypothesis is the RNA World hypothesis (second answer) which suggests that the formation of RNA that could replicate (possible due to mutation or evolution), led to life that could preserve its genetic integrity through replication (greater stability to the organism) and create lipid bi-layer membranes/other organelles. Some scientists support the Metabolism First Hypothesis, while others are skeptical (this goes for the RNA World Hypothesis as well). However, the RNA World Hypothesis is for more reasonable in the fact that its main point is the fact that RNA molecules were able to replicate and maintain genetic stability despite early Earth conditions. Although either hypothesis could explain why all organisms share the same genetic code, the RNA World Hypothesis better explains the universality of DNA/RNA of genes that we see today.
The correct answer is D Fish ( someone asked me to explain why d is the answer) A sponge obviously doesn’t have a brain, a hydra is an organism and organisms don’t have brains ( hydra also doesn’t have eyes)
Answer:
<h2>A</h2>
Explanation:
1. Nucleus is a ball like structure which is found in the center of the cell only in eukaryotic cell, true nucleus is absent in prokaryotes.
2. Nucleus contains nucleic acid and is have double membrane which contain pores though which transport of molecules occurs.
3. DNA replication , transcription and RNA splicing occur in the nucleus.
Answer:
Parenchyma Cells, I believe
About 20 astronaut have faced fatalities during the space program.
