An important difference between single-unit and multiunit smooth muscle is the a. numerous gap junctions in single-unit smooth muscle, which allow many cells to work together as a sheet. b. longer actin and myosin filaments in multiunit smooth muscle, which allow coordination of contraction. c. ability of single-unit fibers to change into multiunit fibers when advantageous. d. closely controlled individual fibers in single-unit smooth muscle to allow fine control and graded contractions by selective activation.

the answer will be a) proteins i believe

the correct answer is: b. pantala flavescens, because these organisms would have a high level of genetic variation due to sexual reproduction.  

because involves two organisms (parents) whose genetic material combines, sexual reproduction leads to genetic variation in new generations of offspring. the offspring is an unique organism, with new genome, more protected with the higher ability to adapted. this process is fundamental to evolution.

the two answers are a, the population of birds with large beaks will increase on the island, and c, the trait for large beaks will be passed on to future generations through natural selection. the reason for that is because if the birds that have beaks developed for eating small seeds lose all of their food, they will go hungry and eventually starve because they physically cannot eat the large seeds, therefore making the population of large beaked birds higher. also, if the trait of large beaks are dominant on the island over small beaks, then over time the large beaked birds will reproduce more and more, while the smaller beaked birds will reproduce less and less because they can't survive with the food provided. that leads to the trait of small beaks disappearing and the trait of large beaks taking over the island.