every cell has work to do but different cells may have different jobs in multicellular organisms, cell with the same type of job often work together. These group of specialized cell from tissue in turn, tissue often group together to form larger units called organs the heart is an organ; so is the stomach.
Oparin and Haldane's theory and Miller's experiment are the proof that long complex molecules that carry information such as DNA, might have formed on early earth.
Explanation:
Oparin and Haldane Hypothesis states that life on Early earth could have evolved by chemical evolution.
Oparin and Haldane said that the reducing atmosphere of the early earth caused simple inorganic molecules to react by using sunlight and formed molecules like amino acids and nucleotides.
These monomers combined to form polymers, they would have attained self-replicating tendency eventually these would have assembled into structures and these macromolecules had also made membrane-bound organelle.
Although this hypothesis is not fully accepted but part of it which talks about formation of molecules is accepted.
Millers and Urey in their experiment created an artificial reducing environment like that of early earth. They used a heated pool of water, atmospheric gases like H2O,CH4,N2, NH4 and sparks of electricity. After running the experiment for some days they found that amino acids, sugars, lipids and other organic molecules had formed.
Their hypothesis is not fully accepted but part of is evident that organic building block is formed from inorganic constituent on the earth.
Answer:
The statement that says "Energy enters a food chain as heat energy and leaves it as light energy" is false.
Explanation:
The energy that enters the food chains, first of all, is light energy from the sun. This energy is assimilated by plants to convert it into chemical energy, through photosynthesis.
When energy flows from producers, plants, to consumers and decomposers, a great amount of <u>energy is lost, in the form of </u><u>heat energy</u>, due to the metabolism of living beings. Additionally, the second law of thermodynamics states that when energy passes from one form to another it leads to disorder in the system, which would also explain the loss of energy.
The true statement is "Energy enters a food chain as <u>light energy</u> and leaves it as <u>heath energy"</u>.
Answer:
The atomic number of phosphorus is 15. It has zero charge because it has 15 electrons.
