What is symbiosis? what are the three major types of symbiosis?

You will create a molecular clock model for an arthropod gene. follow these guidelines to make your model: . your timeline will span from 90 million years ago to the present. the common ancestor in your model is an arthropod that lived 90 million years ago. the gene that you'll track codes for a protein in the species venom . the dna sequence youll track contains 10 nitrogen bases. you can choose the order of the bases and where the mutations occur. this gene mutates at a rate of approximately 0.76 base pairs every 17.1 million years. to build your model,/ calculate the estimated time period it takes for 1 base pair to mutate. the first time period will only show the common ancestor. at the beginning of the second time period, three lineages will diverge from the common ancestor, each with a different mutation in their gene sequences. the first and third descendant species will survive for the rest of the timeline. the second descendant species was extinct 50 million years ago. calculate how long it will take for one full base pair mutation to occur. explain your reasoning by constructing a mathematical equation

How secretion and excretion both are different? explain in simple language.

Which of the following statements is true regarding a basic amino acid? a.) the hydrophilic r group of a basic amino acid will be located on the interior of a protein b.) the positively charged r group of a basic amino acid could bind dna c.) the r group of a basic amino acid would only be able to form covalent bonds with other molecules d.) a basic amino acid would be considered both polar and hydrophobic e.) all of the above