Answer:
A <u><em>receptor</em></u> is a protein that recognizes and responds to a signal.
Explanation:
A receptor is a protein molecule present on the cells on which the signalling molecules can bind and generate a physiological response. Some receptor molecules can also respond to Sun and light. Each type of cell has specific receptors molecules and hence can respond to specific signals. The receptor molecules hence tend to receive signals for a cell. Molecules such as hormones bind to the receptors.
According to Charles Darwin's theory of Evolution by natural selection, organisms that possess heritable traits that enable them to better adapt to their environment compared with other members of their species will be more likely to survive, reproduce, and pass more of their genes on to the next generation.
(n.d.). Retrieved from http://www.nas.edu/evolution/Definitions.html
One word answer:Adaptation:
Answer:
7
Explanation:
There are 12 total pairs of ribs. 1-7 are attached directly to the sternum by costal cartilages, making them true pairs. 8-10 are fake pairs, which means they're attached indirectly to the sternum. And 11 and 12 and free floating ribs, meaning they aren't attached.