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The DNA makes RNA from it that is messenger RNA that goes to RER which has ribosomes responsible for making proteins. The RNA has copied information with help of which it calls out for amino acids for bonding that are then bonded in the protein factory (RER) . Hence the proteins are formed.

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Genes are the basis of genetics and heredity, the are basically building blocks for traits and characterisitics. When genes are expressed outwardly or physically, such as a gene coding for hair or eye color, that is called a phenotype. To understand how a simple gene can make a person's hair brown or blonde, you have to understand the journey they make.

Flow of information diagram: DNA at top, then RNA by transcription, then protein by translation, which produces a trait, shown as flowers at the bottom.

Genes flow from gene to DNA to RNA (through transcription) to Protein (through translation) to protein to phenotype

Genes information is first translated to DNA. DNA or deoxyribonucleic acid is made up of four nitrogenous bases, (A) adenine, (C) cytosine, (G) guanine, and (T) thymine. The order of how these bases are paired is a code for genetic information. The information from that DNA is then transferred to RNA through a process called transcription. RNA, unlike DNA is single stranded and consists of ribose as as the sugar instead of deoxyribose and instead of the base thymine, it has (U) uracil. During transcription, one strand of DNA is made into an RNA strand with complementary bases. So since A pairs with T or U and C pairs with G, if a DNA strand had the sequence AACGGCTTC, its complementary RNA strand would be UUGCCGAAG. That strand it made is called a messenger RNA molecule or mRNA.

1.) What would be the complemetary RNA strand to the DNA sequence AAGTGCCGTGAATGT? (Answer at the end)

mRNA synthesis diagram: a DNA double strand (sense strand AGCTGACCTAGCGGACAA, partner TCGACTGGATCGCCTGTT) and the mRNA strand AGCUGACCUAGCGGACAA below.

The next step is from RNA to protein through a process called translation. The mRNA molecule created from transcription is then used to make animo acids that code for proteins. Translation occurs at ribosomes, the mRNA enters the ribosome where it is coded and translated into which amino acid will be produced. There are 20 amino acids and three of the base pairs code for which amino acid will be produced, this is called the triplet code.

Circular codon chart read from the inside out: first base ring (U, C, A, G), then second base, then third base on the outside, with amino acids and stop codons at the edge.

Starting at the first base inside and going outward utnil you reach the last one is the animo acid the triplet makes. When a stop codon is reached, the process ends. UAA, UAG, and UGA code for stop codons. AUG codes for methionine.

2.) What would be the animo acid that would be the product of the triplet CAG?

That chain of amino acids is then condensed to form a protein. These proteins then in turn control physical characteristics, or phenotypes. Phenotype should not be confused with genotype, genotype codes for a phenotype. Phenotype is the physical characteristics of something that can be seen, such as hair color.

3.) What is the correct flow of genes to phenotype?

Cartoon of genotype to phenotype: a pair of chromosomes labeled Genotype, an arrow reading 'Codes for', and a brown mouse labeled Phenotype.
Three butterfly diagrams: genotype AA and Aa both have dark wings, while genotype aa has light wings. Each genotype's alleles are shown as labeled markers on the body.

Genotype coding for wing color of butterflies. Just the presence of one dominant allele codes for a dark phenotype, the presence of two recessive alleles code for light wing color.

Concept check answers:

  1. UUCACGGCACUUACA
  2. Glutamine
  3. Gene to DNA to RNA to animo acid to protein to phenotype

Type a concept, like “slope” or “photosynthesis”.

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