Read each scenario below and then complete the paragraphs to illustrate how specific enzymes catalyze various metabolic reactions. Responses will be used more than once.

Scenario 1:
Lactase is produced within the small intestine. Its role is to break down lactose sugars into the simple sugars glucose and galactose. Individuals lacking lactase are considered to be "lactose intolerant".
In scenario 1, lactase is the , lactose sugar is the and the simple sugars are the .
Scenario 2:
When strands of DNA are growing, DNA polymerase recruits nucleotides to create the growing DNA strand. This allows for DNA replication to occur
In scenario 2, DNA polymerase is the , the nucleotides are the and the newly grown strand is the .
Scenario 3:
Rennet is a substance found in calf stomachs to aid in milk digestion. It contains a molecule called rennin which causes milk to curdle, producing curds and whey. Rennin is an important part of cheese production.
In scenario 3, rennin is the , milk is the and curds and whey are the of this reaction.

Why was the sample heated in step 5? describe the chemical principles involved in the reasoning behind this step?

The scales shown in the introduction measure mass, or the amount of matter in a particular object. the scientific law of conservation of mass states that matter cannot be created or destroyed during a chemical reaction, but it can change from one form to another. did the simulation support this scientific law? explain why or why not.

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