From the heart, this blood is pumped to the lungs, where carbon dioxide passes into the alveoli to be exhaled. The heart then pumps the oxygen-rich blood through vessels to your cells. As the blood nears cells, it enters capillaries again. Oxygen moves out of the capillaries and into the cells. Cells send carbon dioxide and other wastes through the capillaries into the blood to be carried away. Next, blood flows back toward your heart to be pumped to the lungs. Carbon dioxide flows through capillaries back into the lungs. The carbon dioxide then flows out of the body back into the air. Every time we take in glucose in the form of food and breathe in oxygen, we exhale carbon dioxide and water vapor. The blood picks up more oxygen at the lungs, and the cycle begins again! Water transport across cell membranes occurs by diffusion and osmosis. The cell‐membrane osmotic water permeability varies from cell to cell, depending on the composition of the lipid bilayer and the presence or absence of water pores. The two main pathways for plasma‐membrane water transport are the lipid bilayer and water‐selective
From the heart, this blood is pumped to the lungs, where carbon dioxide passes into the alveoli to be exhaled. The heart then pumps the oxygen-rich blood through vessels to your cells. As the blood nears cells, it enters capillaries again. Oxygen moves out of the capillaries and into the cells. Cells send carbon dioxide and other wastes through the capillaries into the blood to be carried away. Next, blood flows back toward your heart to be pumped to the lungs. Carbon dioxide flows through capillaries back into the lungs. The carbon dioxide then flows out of the body back into the air. Every time we take in glucose in the form of food and breathe in oxygen, we exhale carbon dioxide and water vapor. The blood picks up more oxygen at the lungs, and the cycle begins again! Water transport across cell membranes occurs by diffusion and osmosis. The cell‐membrane osmotic water permeability varies from cell to cell, depending on the composition of the lipid bilayer and the presence or absence of water pores. The two main pathways for plasma‐membrane water transport are the lipid bilayer and water‐selective