Which statement is true according to hooke's law? i think the answer is a! tell me if i'm right
a. if the force on a spring doubles, the distance it stretches doubles. b. if the force on a spring doubles, the springs length increases by some unknown amount. c. if the force on a spring doubled, the distance it stretches is halved.
d. if the force on a spring doubles, the springs length decreases by the same unknown amount.
1) homologous features:
these are the features or structures that have similar structure in several different organisms but function in a unique way in all of them. these structures indicate anatomical similarities as well as same ancestry of different organisms. for example, the forelimb of birds, humans, dogs and whales, perform different function in all these organisms. but when we analyse the layout of bones or layout of arrangement, we find that it is very similar across all of them. this indicates that, the ancestor of all these organisms was was, but with the passage of time when organism dispersed, and environmental conditions changed, it was evolved into different organisms as per favorable conditions.
2) molecular biology:
as we know that all living organisms are a compilation of billions and trillions of unique biological molecules, that group in unique fashion to constitute whole organism. interestingly, some biological molecules and the process of their formation can provide sound evidences of evolution. for example, dna, sequence of nucleotide in dna, amino acids, process of transcription, translation etc.
the study of evolution through molecular uniformity has led to the foundation of a novel branch of evolution called phylogenetics. the sequence of nucleotides in dna is used to find the best possible ancestor of any organism. for example, phylogenetic analysis has found that the origin of eukaryotes is from prokaryotes over the period of time.
3) fossil records:
fossils are the preserved remains of previously living organisms or their traces, dating from the distant past. this don't means that fossils represent complete skeleton of an organism, because many organisms don't even fossilize and those who fossilize don't have complete remains.nonetheless, the fossils that humans have collected offer unique insights into evolution over long timescales. for example, study of horse fossils has enabled the scientists to reconstruct a large, branching "family tree" for horses and their now-extinct relatives.
there are 64 codons that is contained in the mrna.explanation
the codons contained by the mrna produced by dna consist of three nucleotides and a single amino acid. the mrna uses uracil nucleotide as a base. the genetic code is known as a codon. there are almost sixty four codons but three of which do not code for amino acids. the codons found in the base pairs of strands of mrna during the process of translation.