Answer:
by looking at their physical features, the fossil record, and dna sequences
Answer:
1. A. carbon,hydrogen,nitorgen and oxygen
2.C. Nucleotides
3.A.Brain
4.D. Polysaccharide
5. B.Amino acids contain nitrogen; fatty acids and sugars do not.
Scientists found that the first living things were likely prokaryotic because eukaryotic are evolved from the prokaryotic only.
<h3>What do you mean by Natural selection?</h3>
Natural selection may be defined as favorable variations that assist the organisms to survive and reproduce in a particular habitat.
Individuals that are better suited to their environment are likely to have more offspring and pass their genetic material on to future generations. This theory is referred to as Natural selection.
Scientists hypothesize that oxygen began to accumulate in the Earth's atmosphere after the appearance of living things with the ability to Photosynthesize.
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The given statement is TRUE.
A positive feedback loop causes a self amplifying cycle in which a physiological change leads to even greater change in the same direction.
A negative feedback loop is a process in which the body senses a change, and activates mechanisms to reverse that change.
What is a positive feedback loop?
In nature, a positive feedback loop happens when the outcome of a reaction increases that reaction. A positive feedback loop pushes a system further away from the equilibrium goal if we consider a system in homeostasis. It takes place when something needs to happen quickly and does this by enhancing the effects of a product or event.
<u>Example</u> : Ripening of fruit
In nature, there is a strange phenomenon when a tree or bush may suddenly and silently begin to ripen all of its fruit or veggies. This is the first instance of a beneficial biological feedback loop we've found. If we see an apple tree with many apples, they all appear to ripen over night, going from being unripe to ripe to overripe. The first apple to ripen will mark the start of this. It releases ethylene (C2H4) via its skin when it is ripe. The apples nearby ripen as a result of being exposed to this gas. As soon as they are ripe, they too begin to generate ethylene, which continues to ripen the rest of the tree in a manner akin to a wave.
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