Answer:
A
Explanation:
Living organisms adapt to their moves and positions in response to the environmental changes for their protection or to their advantage. When an entity reacts to the changes in its surroundings, it is referred to as stimulus while the reaction to the stimulus is referred to as a response. Common stimuli are sound, light, air, heat, smell, taste, water and gravity.
Think of burning your finger of fracturing your bone without any pain sensation. It may certainly sound like a superpower or an ideal situation, however, when it comes to the standpoint of survival, it can be disastrous.
It is a characteristic behaviour of living entities to respond to stimuli with the intervention of the Nervous System. It is an organ system ascribed to send signals from the spinal cord and the brain throughout the body and then back from all the body parts to the brain. Neuron acts as the mediator and is the basic signalling unit of the Nervous system.
Pain is the body’s way of letting us know that something is not right. It can prevent further injuries or push us to seek medical attention. Moreover, all of this is possible because humans can respond and react to stimuli due to control and coordination among the various organs and organ systems.
Control and Coordination in simple multicellular organisms take place through only the Nervous system which coordinates activities of our body. It is the control system for all our actions, thinking, and behaviour.
Answer:
No, CREs usually don't account for differences in gene expression levels.
Explanation:
<em>Cis</em>-regulatory elements (CREs) are non-coding DNA regions that regulate adjacent gene <em>transcription</em>. They usually do it by binding to transcription factors. They are in charge of influencing the rate of which transcription occurs, and less with how much a gene is expressed. On the other hand, trans-regulatory elements are DNA sequences that encode for upstream regulators that can modify or regulate <em>gene expression levels</em>.
Therefore, cis elements are not really in charge of expression levels, mostly transcription rates of single genes, rather. Trans elements are more involved in expression levels.
