The answer is D. the curculitory system transports hormons.
I think its A
A dog will bark at animals and cars, but only if the environment permits.
-Seth
The Sun's outer gases extend far beyond the photosphere (Figure 6). Because they are transparent to most visible radiation and emit only a small amount of light, these outer layers are difficult to observe. The region of the Sun's atmosphere that lies immediately above the photosphere is called the chromosphere.
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 and Explanation:
The steps of the sliding filament theory are:
Muscle activation: breakdown of energy (ATP) by myosin.
Before contraction begins, myosin is only associated with a molecule of energy (ATP), which myosin breaks down into its component molecules (ADP + P) causing myosin to change shape.
Muscle contraction: cross-bridge formation
The shape change allows myosin to bind an adjacent actin, creating a cross-bridge.
Recharging: power (pulling) stroke
The cross-bridge formation causes myosin to release ADP+P, change shape, and to pull (slide) actin closer to the center of the myosin molecule.
Relaxaction: cross-bridge detachment
The completion of the pulling stroke further changes the shape of myosin. This allows myosin and ATP to bind, which causes myosin to release actin, destroying the cross-bridge. The cycle is now ready to begin again.
The repeated cycling through these steps generates force (i.e., step 2: cross-bridge formation) and changes in muscle length (i.e., step 3: power stroke), which are necessary to muscle contraction.
