Answer:
Active transporters or ion pumps are transporters that convert energy from various sources—including adenosine triphosphate (ATP), sunlight, and other redox reactions—to potential energy by pumping an ion up its concentration gradient.
Explanation:
Answer:
C) The continents were once connected.
Explanation:
All the continents were once part of the super-continent called Pangaea. Continental drift split it into fragments and led to the formation of the present-day continents. Since all the continents were connected, some of the cacti native to tropical western Africa must have been carried to present-day America.
The cacti populations present in America and tropical western Africa accumulated genetic variations to get adapted to the prevailing environmental conditions. Separation of continents by continental drift led to their geographical isolation and prevented any interbreeding between the populations. Over generations, the cacti present in two continents evolved into separate species.
Explanation:
Hurricanes form over the warm ocean water of the tropics. When warm moist air over the water rises, it is replaced by cooler air. The cooler air will then warm and start to rise. This cycle causes huge storm clouds to form.