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 you’ll 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.

the electromagnetic energy from the sun arrives in the form of visible and invisible light.

cells use diffusion to get substances in and out of themselves. that diffusion will occur across the cell membrane or the outer covering of the cell. because we are talking about the surface of the cell, surface area and volume are  important factors here. as a cell increases in size, its surface area and volume increase as well.  we call that the surface area to volume ratio (sa: vol).  but the catch is that  volume increases at a greater rate than surface  area. in other words, as a cell gets bigger, the sa: vol gets smaller. so a really small cell like bacteria is mostly cell membrane (surface) with very little contents (volume). a really big cell like an egg, is mostly insides with a super thin membrane. so what ends up happening is that the cell cannot efficiently diffuse all of the stuff it needs in/out to survive. therefore cell size is limited to about 100mm. so how do we make organisms bigger than 100mm? cells divide! by dividing and becoming multicellular, organisms are able to grow!   check out the diagrams i attached to see the effect of sa: vol. i hope this ! good luck!

after a the power stroke, adp is released, but the cross-bridge formed is still in place. atp then binds to myosin, moving the myosin to its high-energy state, releasing the myosin head from the actin active site.