Early pre-cambrian period the atmosphere consisted only of nitrogen and carbon dioxide without oxygen.
<span>A Prokaryotic cell does not contain a nucleus. It only contains one chromosome and is a single-celled organism. It was the only form of life on earth for millions of years. Examples of a Prokaryotic cell are the different types of bacteria present today.
</span><span>Autotrophs obtain energy by the process of photosynthesis. Any living organism need energy to survive and autotrophs are no different. Two types of autotrophs are present and they are Photoautotrophs and Chemoautotrophs. The Photoautotrophs rely on the energy produced during the process of photosynthesis and the Chemoautotrophs get their energy from most of the inorganic substances. Phtoautotrophs actually get their energy from the sunlight and then convert it into reusable form. In case of Chemoautotrophs ammonia is an important source of energy for them.</span>
Answer:
D variations in individuals are not heritable
Explanation:
Genetic variation in individuals is what drives evolution. In a population of individuals in an environment, with the adequate resources, overpopulation can occur. However, resources are usually a limiting factor for population growth: there is not sufficient food/shelter etc. for everyone to survive.
Some individuals are better suited to success in the environment. This is because of random variation in their DNA that has arisen that give them a selective advantage. This allows them to thrive, take advantage of the limited resources over other members of the population, and be more likely to survive to reproductive age. This is natural selection.
Because this variation is genetic (in the DNA), they can then pass it on to their offspring. Over time, this leads to evolution over time.
e. There are haploid, diploid, and triploid cells.
Answer:
Mitosis makes new diploid cells. Meiosis makes haploid cells. Examples are egg and sperm