During contraction, the filaments slide past he thick filaments, shortening the sarcomere. The thick and thin filaments do the actual work of a muscle, and the way they do this is pretty cool. Thick filaments are made of a protein called myosin. At the molecular level, a thick filament is a shaft of myosin molecules arranged in a cylinder. Thin filaments are made of another protein called actin. The thin filaments look like two strands of pearls twisted around each other.
The next time he goes surfing, he will get tired a lot faster and will run out of breath a lot faster. He will also feel a lot more tired quicker than he used to.
Answer:
sponge
Explanation:
at first i was about to say cheese -_-
