The answer is; the skeletal system and the nervous system
The skeletal system (muscle and bone) give you rigidity and enable your legs to support your weight. The muscles also act on the bone as a fulcrum allowing it possible for them to contract and make motion possible.
The nervous system is important in the coordination of movement. The brain is the center for locomotor action. This ensures you are able to place one foot in front of the other in sequence and moving your arm in concert.
Darwin lived in a time where natural selection was a strange theory among scientists and researchers. This was especially true when other researcher Lamarck argued that organisms passed on helpful traits to their offspring, that they magically could form a new trait to adapt to their environment and then pass it onto their offspring. For example, if a giraffe was too short to reach food, it would grow a larger neck in its lifetime and then pass that trait onto its offspring. Darwin argued that, through the process of survival of the fittest, that short giraffe would die off and never receive the chance to pass on its shortness to future populations. Thus, taller giraffes would survive— they can reach food, shorter giraffes can’t— and the short genes would disappear. The fact that Darwin was introducing a new theory that nobody was used to at the time was peculiar, so he had few people on his side until long after his observations.
Another problem Darwin had was the lack of technology. To travel, Darwin would have to use boats to reach far away places, and of course, this took time.
The final problem Darwin had was the extra time it took for evolution, a process that can take up to millions of years. Evolution didn’t occur over night— it took time for Darwin to conduct experiments, observe, conduct them again, come to a conclusion, and so on.
Hope this helped a little!
<span>Correct matches: chemicals with their descriptions.
1. abscisic acid ( is the hormone that regulates survival functions of a plant, such as the opening and closing of stomata)
2. auxins (chemicals produced in plants that are characterized by their ability to induce cell elongation and cell division in stems)
3. cytokinins (chemicals that helps plant cells divide)</span>
<span>4. ethylene (a hormone that promotes ripening of fruit or blooming of flowers) </span>
<span>5. gibberellins (chemicals produced by plants that stimulate stem elongation, seed germination, and flowering) </span>
Answer:
Explanation:
Water vapor is the most important greenhouse gas. ... However, water vapor does not control the Earth's temperature, but is instead controlled by the temperature. This is because the temperature of the surrounding atmosphere limits the maximum amount of water vapor the atmosphere can contain.
