Most of the marine animals have a stream lined body, which means, they have a sharp and pointed at the front. The pointed front of the organism allow to cut the resistance of the water. In case, the body is not pointed at the front and it is blunt, the water current and flow would resist the movement of the organism further. So, for the locomotion purpose, it is important to have a streamlined body. Further smooth and hair less body also decrease the resistance during the movement in the water.
<h2>Answer</h2>
Spontaneous generation does not support cell theory because
- <u>A. All cells arise from preexisting cells</u>
Correct me if I'm wrong
<h3>#CarryOnLearning</h3>
Explanation:
Food gives us energy and builds our body. If we do not eat regularly, we will become weak.
Answer:
This suggests that the moustache is a releaser for aggression.
Explanation:
<em>Fixed action patterns</em> are instinctive programmed responses in different species that are triggered by a specific external sensory stimulus. These stimuli are called sign stimuli or releaser. When the sign occurs, the animal starts a sequence of acts in response to the stimulus and continuous until the series of actions is completed.
The black feathers resembling a mustache in a <em>Northern flickers</em> male are an external sensory stimulus. This trait that can provoke another male to respond aggressively, as a f<em>ixed action pattern</em>.
This trait might be considered as an <em>unconditioned stimulus</em>, which <em>provokes an unlearned or reflex reaction</em>. These aggressive responses are triggered by reflex.
Bird migrations began with the recession of the glaciers during the ice age. You will notice a great increase in insects in the spring time and early summer.The birds moved North to take advantage of this increase in the food supply that followed the warming in the spring and early summer. Their reproductive organs temporarily developed so they could lay eggs and raise a family. Look at the early flush of Night crawlers in the moist times of the early rains. By mid summer most of the insects have matured, mated and died. Their eggs have hatched and turned to larva and moved underground until next spring. The shortening of the days causes the reproductive functions to decrease and signals the birds that the food will soon become scarce. They move back to the area that makes it the easiest to find food and avoid freezing. which of course is the warmer climates nearer the equator. Not all birds move past the Tropics at approximately 30 degrees. Some like Chickadees may move down from Mi or Mn or Canada only as far south as Indiana. Some migrations may be quite short. For example from the mountains down to the plains. They don't generally reproduce in the warmer winter climes they migrate to. In the spring time they migrate along paths of the retreating glaciers. As the climate warms away from the tropics the birds follow the emerging insects etc to the birds selected breeding grounds.with increased insects and longer days to feed the hatching's. It is necesary to understand why they move to cooler climates in the summer to under stand why they move to eh warmer ones in the fall. As the days shorten the food supply dwindles and the babies have fledged. They move to warmer climates in winter to rest and refuel for the next years migration.
