Smooth muscle has some unique properties, such as low energy usage, and the ability to maintain contraction over long periods. Tie these properties to the function of smooth muscle in the body.

Video transcript

Everyone. Let's take a look at this question together, which of the following is responsible for the ability of smooth muscle to maintain contraction over long periods of time. Is it answer choice? A high energy usage. Answer choice B latch bridges, answer choice Catp or answer choice D Glycogen. Let's work this problem out together to try to figure out which of the following answer choices allows smooth muscle to maintain contraction over long periods of time. So in order for the smooth muscle to maintain contraction over long periods of time, it requires constant contraction. However, this constant contraction must include low energy usage. And in order for that constant contraction in the muscle, it requires something to be attached to the acting filaments. So looking at our answer choices, what is something that is attached to acting to allow that constant contraction and includes low energy usage. Well, we know that answer choice. A high energy usage is just a characteristic of muscle activity and doesn't explain this ability. So answer choice A can be eliminated and we know that answer choice Catp or Adinos tri phosphate is what the cells use for energy and is required for muscle contraction. So A TP is also incorrect. And we know that answer choice D glycogen is a form of stored glucose in the muscle cells, which can be broken down to provide energy for that contraction. But it is not used to maintain that contraction over long periods of time. So answer choice D is also incorrect, which leaves us with only one remaining answer choice, which is answer choice B latch bridge is the correct answer. Since a latch bridge is a specialized type of a Myosin cross bridge that is found in those smooth muscles forming a bridge by attaching to ain allowing for that constant contraction with the low energy usage. Thanks to its low A TB ACE activity. No answer. Choice B is the correct answer. I hope you found this video to be helpful. Thank you and goodbye.