Cells must use energy to move a substance against a concentration gradient (i. e., from a compartment with a low concentration of the substance to a compartment with a higher concentration). which of the following processes would require a cell to expend energy? choose all of the correct answers. transport of sodium ions out of cells transport of sodium ions into cells transport of potassium ions out of cells transport of potassium ions into cells transport of calcium ions out of cells transport of calcium ions into the cytoplasm of a cell from the ecf transport of calcium ions out of the cytoplasm of a cell and into an organelle that has a high concentration of calcium ions. transport of calcium ions out of an organelle that has a high concentration of calcium ions and into the cytoplasm of a cell.

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