A frog heart has 3 chambers, 1 ventricle and 2 atria. One atrium (the right) receives deoxygenated blood from the frog's body (in the systemic circulation) and then pumped to the single ventricle wherein it will go to the lungs to be oxygenated. Another atrium (the left) received oxygenated blood from the lungs then pumped to the single ventricle wherein it will go to the systemic circulation. In the single ventricle, some form of mixing of the oxygenated and deoxygenated blood happens but since the frog is a cold blooded animal, the decrease in the concentration of oxygen is deemed superficial.
This advancement allows the frog to live on land using the lungs as the primary organ for oxygenation of the blood.
True. They were originally formed by the growth of layer upon layer of cyanobacteria, a single-celled photosynthesizing microbe that lives today in a wide range of environments ranging from the shallow shelf to lakes, rivers, and even soils. It is a prokaryote, with no nucleus.
A mutation is a change in trait. For example people who are lactose intolerant are normal, but people that can can drink milk without a problem have mutated. Hopefully this makes sense and helped.
What? im aorry i dont understanf
