Answer:
When calcium concentration increases during depolarization, it shifts the conformation of troponin and tropomyosin, and actin is able to associate with myosin. As calcium is taken up again by the sarcoplasmic reticulum the muscle cell relaxes.
Answer:
Increase in transcription
Explanation:
Transcription is the process of forming RNA from DNA. It can be controlled by many factors like a repressor. Repressor can bind to the operator region of the promoter and hinder the movement of RNA Polymerase enzyme, halting the process.
Here, it is given that the repressor needs to first bind to an effector molecule X. Once it binds to X, it is activated and then it can bind to operator of gene A to inhibit its transcription. If the X binding domain on repressor is mutated it wont be able to bind to X. Thus it wont get activated and wont be able to attach to operator region to inhibit transcription. Hence, transcription process will keep going on uncontrolled.
Answer:
B
Explanation:
Oxygen is the final acceptor of electrons in the process of oxidative phosphorylation. Without oxygen, the process becomes jammed with electrons.
The earth is surrounded by <em>a layer of</em> gases called the <em>atmosphere</em>. The atmosphere is very <em>important </em>to life on <em>Earth</em> and does many <em>things</em> to help protect life and help<em> life </em>to survive.
The atmosphere absorbs the <em>heat</em> from the <em>Sun </em>and keeps the heat <em>inside</em> the atmosphere helping the <em>Earth </em>to stay warm, called the <em>Greenhouse </em>Effect.
