Answer:
True and The respiratory system is a biological system consisting of specific organs and structures used for gas exchange in animals and plants
Answer: Option E (B and D are the only examples.
Mediterranean ecosystem with hot dry summer and fire can be found on various continents across the globe. Plants in these ecosystem have evolve similar adaptations to survive these circumstances.
Echidnas are egg laying mammals that live in Australia and new Guinea. They are sometimes known as spiny anteaters since they are covered in spines and mostly eat ants and termites. As such they resemble south American anteaters and hedgehogs but are not closely related to them. Instead echidnas descended from an aquatic platypus like ancestor.
Explanation:
Divergent evolution is a process where different organisms with different anscetors evolve independently and develop similar traits due to their adaptation to similar environment.
Another example is the similarities between hummingbird and hummingbird moth, the evolved from different ancestors and yet posses similar characteristics.
The OLFACTORY AND THE GUSTATORY SYSTEMS have receptors which die out after sometimes because of direct exposure to the environment.
The olfactory system has to do with the perception of smell while the gustatory system has to do with taste stimuli. For these two basic sense organs, their perception rate is always highest when they are newly exposed to a stimuli, after continuous exposure to the stimuli their receptors die out.
Well, scientists depend on science.They use the process of observation. But there are processes for these. The processes are;
Asking a question; Scientists wonder how specific happenings can be explained, they look for an answer.
They perform research; the scientists study the particular thing, and look for reasons for a particular happening.
They form a hypothesis; a hypothesis is a statement which is not universally true, they are observations that haven't been agreed upon.
They test their hypothesis; they perform experiments to find out if their hypothesis is true.
They analyse the data and draw a conclusion; they record their hypothesis and write down their end result.
They pass across their result; they pass their new observation across to other people.
Hope i helped. Have a nice day.
The Precambrian time refers to the time 4.5 billion to 542 millions year ago. This period is characterized by having reduced atmosphere and included reduced compounds. Scientists believed that atmosphere at that time was devoid of free oxygen and CO2 was present in excess. Before the complex life evolved on the Earth, the Precambrian Earth's ocean contained dissolved carbon dioxide.
