The right ventricle pumps the oxygen-poor blood to the lungs through the pulmonary valve. The left atrium receives oxygen-rich blood from the lungs and pumps it to the left ventricle through the mitral valve. The left ventricle pumps the oxygen-rich blood through the aortic valve out to the rest of the body.
All plants have a cell wall, all mammals have a cell membrane. a cell membrane is semi-permeable it allows mammal cells to absorb needed nutrients, oxygen and deposit waste into the blood stream where it is excreted through urine and feces. a plant cells nutrients are absorbed through the root system and leaves, waste is excreted in the form of oxygen through the plant itself.
Answer:
It is B
Explanation:
I had this question on my test last week
My Answer: The death rate begins to fall, but birth rates remain high for a time.
Why?: Many of our countries are in Stage 2, that is why the government is concerned about our overpopulation.
Hope I helped! :D
It is a unicellular organism. Yeast are a polyphyletic group of species within the kingdom fungi. They are predominantly unicellular.
