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>
A) genotype
Because the genotype means the genetic make-up of the cell, so saying that the genes of the plant are homozygous dominant show this genetic make-up of the plant.
Answer:
Climate and slavery
Explanation: Slaves were the main reason that there was food before the end when Abraham was president. Climate and slavery can change how the crops were grown. I'd also say the geography was messed up then due to the climate. (sorry if wrong Q-Q)
A star is formed within the clouds of dust. These clouds of dust are scattered throughout the galaxy. These dust clouds are called as nebula. The turbulence inside the dust clouds rise to form knots. These knots along with sufficient mass causes gas and dust to collapse with the help of gravitational force. These sequence of steps leads to form a star.
