The answer is; Ca2+ from the sarcoplasmic reticulum binds to tropomyosin
When the ca2+ ions bind to the tropomyosins on the actin filament, the tropomyosins are displaced and this exposed the myosin binding sites on the actin filament. The ADP + Pi (attached to the myosins heads), from the previous cycle, is released allowing the cocking of the myosin heads hence pulling on the actin filament. ATP then binds on the ATP-site on the myosin heads casing a release of the myosin heads from their site in the actin. This also hydrolyzes the ATP. This is one cycle of the cross-bridge cycle.
Answer:
Downstream, along the river is vague and middle of town makes no sense, upstream would mean that the pollution would run right past the town and cities and could pollute the town's and cities
Answer:
Wild Fires
Explanation:
Wild Fires are caused many factors including discarded cigarettes . These can be prevented when people stop to smoke in the forest and obey the fire protocols in the forest
Answer and Explanation:
The Immune System. It comprises the white blood cells, lymphatic system, etc. The immune response is the production of antibodies in response to antigens present in pathogens and other foreign matter.
The leukocytes are formed in the bone marrow of long bones and lymph nodes. Their function is to protect the body from invasion of foreign material like bacteria and viruses( pathogens). They help fight against infections by engulfing and digesting pathogens and production of antibodies which are proteins that bind to pathogens. Their number increases greatly during infections.