Answer:
The animals present body structure is due to evolution. It is seen in each part including the structure of the heart. The vertebrate heart becomes complex from a simpler form.
Invertebrates, the heart of fishes is two-chambered having one auricle and one ventricle. The deoxygenated blood gets purified in the gills. They are aquatic and no lungs for breathing. The hearts pump a mixture of oxygenated and deoxygenated blood to the body.
The amphibians and reptiles have 3 chambered heart as they lead terrestrial mode of life. The gills modified into the lungs. The left auricle receives pure blood and the right auricle receives deoxygenated blood. The blood purified in the lungs and in the ventricle, both types of blood get a mix. The ventricle pumps the mixed-blood throughout the body.
In the case of birds and mammal, the heart is 4 chambered and the oxygenated and deoxygenated blood are separated. These two are higher vertebrates. No mix of pure and impure blood, the body receives only the oxygenated blood.
This shows to construct the phylogenetic tree of vertebrates - the fishes should be in the bottom, and above it amphibians, reptiles, then, mammals and birds on the top branch of the tree. As the chambers and structure of the hearts modified one after another.
<span>Evolution can best be summed up by statement D - change in a population through genetic variation over time. The other statements do not refer to evolutionary changes, as these are changes that occur slowly, rather than suddely or with speed.</span>
Activation energy is what the type of energy is called
D i think is the answer most of all
Answer:
Please see below
Explanation:
The white board displays helpful info with regards to a QR scanner associated with the day's lesson plan. The shelves on the far end of the classroom holds up relevant books and other objects that will prove educational for the students. Some schedules have been put up too for the ease of the students.