The correct answer is that "t<span>roponin holds the tropomyosin in place on the actin".
In excitation-contraction coupling, tropomyosin prevents the interaction between actin and myosin in resting muscles. In the event of excitation, there is release of calcium from the sarcoplasmic reticulum wherein the troponin will bind this calcium and will release tropomyosin and expose myosin enabling it to attach to actin and therefore facilitating muscle contraction.</span>
Answer: B
Explanation: Because Light and thermal are two different things of heat and if one of the cores of heat gets any cooler than it is than it may burn out and there wwill no longer be heat so the food brin come in at the middle (Core) of the heat and just like a microwave it had different heats but its core of the heat stays the excact same
The external ear structure is called the Pinna.
The Pinna helps to channel sound waves into the ear.
Many animals have the ability to move their pinna towards the direction of sound.
I have attached an image of a dog's ear to show you the external structure called the Pinna.
I hope this helps! I'm happy to answer any other questions you might have :)
[Image sourced from: https://www.msdvetmanual.com/dog-owners/ear-disorders-of-dogs/ear-structure-and-function-in-dogs]
That thing is called abrasion.