Answer :3. similarities among vertebrate forelimbs suggest that they evolved from a common ancestor.
Explanation:
The study of differences and similarities in the anatomy of different species is comparative anatomy. It is based on the concept that
1.)Homologous structures which are present in different species, because they have a common decent and must have evolved divergently from a shared ancestor. Theses anatomic structures may not be used for the same purposes. For example the forelimb of fox and whale.
2. Some structures (Analogous)which are similar in different organisms must have evolved ,(acquired through natural selection) through convergent evolution in similar environment, and not inherited from a recent ancestor. These organisms usually use these structures for a common purpose. For example the streamline body shape of shark and porpoises, which though are used for a common purpose of swimming, were inherited from different ancestors.
. Example of comparative anatomy is the common bone structures in forelimbs of fox, whales, bats, and humans. These appendages is made up of the same basic parts; despite serving different functions.
Comparative anatomy helps scientists in classification of organisms based on their similar characteristics of their anatomical structures.
The biggest challenge is rejection. Sometimes the human body will not accept the pig organ unfortunately.
Hope this helped. Good luck !
Gaurd cells is right answer that is option C .
Hope it helps.
Heart rate is controlled by the two branches of the autonomic (involuntary) nervous system. The sympathetic nervous system (SNS) and the parasympathetic nervous system (PNS). The sympathetic nervous system (SNS) releases the hormones (catecholamines - epinephrine and norepinephrine) to accelerate the heart rate. The parasympathetic nervous system (PNS) releases the hormone acetylcholine to slow the heart rate. Such factors as stress, caffeine, and excitement may temporarily accelerate your heart rate, while meditating or taking slow, deep breaths may help to slow your heart rate.
