Quizloet Depolarization of a cardiac muscle cell occurs as the result of a decrease in the permeability of the cell membrane to sodium. the opening of voltage-gated sodium channels. the closure of voltage-gated calcium channels. the opening of voltage-gated potassium channels. the closure of the voltage-gated sodium channels.

Christie's doctor recommends that she eat 40 grams of protein a day. she's already consumed 50% of her protein recommendation for the day. how many servings of the given snack should christie have to meet her daily protein recommendation?

Which of the following is a difference between active transport and facilitated diffusion? view available hint(s)which of the following is a difference between active transport and facilitated diffusion? facilitated diffusion can move solutes against a concentration gradient, and active transport cannot. active transport involves transport proteins, and facilitated diffusion does not. facilitated diffusion involves transport proteins, and active transport does not. active transport requires the expenditure of cellular energy, and facilitated diffusion does not.

Rease is an enzyme used by plants to break down urea (a nitrogen-containing compound) into carbon dioxide and ammonia. urease urea > > > carbon dioxide and ammonia ammonia is broken down by plants into a nitrogen source plants need to grow. thus, plants could not use urea as a nitrogen source unless it was first converted to ammonia. in soybean plants there are two different kinds of urease, one produced in the seeds and the other produced in the leaves of the plant. three types of soybean plants were used in a set of experiments: normal soybeans and two mutant strains, one lacking the urease in the seeds only (strain 1) and one lacking urease in the leaves only (strain 2). experiment 1 separate areas in a field were planted with normal, strain 1, and strain 2 soybeans. all types of soybeans appeared to grow, flower, and produce seeds equally well. there were no externally detectable differences among the strains. experiment 2 small pieces of plant leaves of equal weight were obtained from each type of soybean plant and separately placed on media in culture dishes. tissue growing in this way will become an unorganized clump of cells referred to as callus. to provide a controlled nitrogen source, half the tissue samples of each type were placed on media containing urea, and the other half of the samples were placed on media containing ammonia. after 30 days, the weight gain for each of the callus samples was determined. results are shown in the table below.