Imagine that Mendeleev's model never existed. What challenges would come about as a result?

Mendaleev classified element due to which it was very easy to study elements.

If the periodic table didn't exist, we would have no visibility of the true atomic number of chemicals. 

Atomic number is the identical property of an element on which all the experiments are based .

If there would not such type of model existed :-

No new discoveries would possible.

This world would be unknown about the chemical properties  log matter.

In school, Brendan has been conditioned to get up from his seat every time he hears the school bell ring.

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for six years an artificial fertilizer is used on a apple orchard the orchard is next to a stream which empties in to a slat water bay during the last 5 years researchers have observed an increase in algae in the bay they have also sampled fish populations in the bay each year apex...

Answer:

Effective food supply was most likely an effect on society that resulted from improvements in blood handling during World War I and World War II.

Need this store of protein: 

The seed consists of three components: embryo, endosperm (sometimes perisperm), and seed-coat. Both endosperm and embryo are the products of double fertilization, whereas the seed-coat develops from the maternal, ovular tissues. The seed habit is a significant advancement in the evolution of higher plants.

Anatomy of seed :-

Seed storage proteins provide a source of amino acids and reduced N necessary for germination and early growth of the seedling.

Rank the following cities in order of earthquake risk from high risk to low risk:

Answer with explaination:

 An attempt to document and identify all biological species living in some defined area, usually a park, reserve, or research area. The numbers of species on earth is rapidly diminishing, knowing what species are around will give us an idea of what we're losing, how our actions are affecting the environment.

99% percentage of errors does our body's "auto-correct",system detect.

Errors associated with protein mismatch and translation is automatically detected by the body system. Once, mismatch occurs, synthesis stops, hence, this error is almost always detected at all times. Therefore, the percentage of errors automatically detected is about 99%.

Explaination:

They perform a valuable service as Earth's cleanup crew. Without decomposers, dead leaves, dead insects, and dead animals would pile up everywhere. Imagine what the world would look like! More importantly, decomposers make vital nutrients available to an ecosystem's primary producers—usually plants and algae.

He solved Ptolemy's model by providing elliptical orbits.he determined that planets travels faster when closer to sun.