Answer:
4. The cell has chloroplasts to turn sunlight into food
Magnolias, laurel, barberry, early sycamores, and palms.
<span>Norepinephrine uses the Second
Messenger System, which means, cells signal to each other what molecules have
been released that will trigger a physiological reaction. </span>
<span>
This phenomenon is activated after the ligand (ion or molecule) is bonded to its receptor
(protein molecule), creating a variation that causes a chain-reaction, that will
finally activate the Second Messenger. The latter will activate intercellular
molecules that will be able to control the cell’s activity. </span>
Quite sure C is correct ;) remember that humans are also placental mammals.
Edwin Hubble used the Doppler effect to determine that the universe is expanding. After years of scientific research and observation of different celestial bodies through a telescope, Hubble found that the light from distant galaxies was shifted towards the red end of the spectrum. This red shift indicates that stars are moving away from us and from each other. This phenomenon is called the 'expansion of the universe', also known as the big band theory.
