Movement in and out of cells

• Diffusion is the movement of particles from a region of higher concentration to a region of lower concentration till equilibrium is reached
• Osmosis is diffusion through a membrane
• Active transport requires energy to move against concentration gradient
• Passive transport does not require energy as it moves with concentration gradient
• Active transport requires energy (ATP) to move molecules against their concentration gradient
• Diffusion is important because it allows gasses like oxygen to enter the alveoli and carbon dioxide to leave the alveoli
• size of particle affects diffusion as the larger the slower the rate of diffusion. The smaller the particle the faster the rate of diffusion
• the temperature affects rate of diffusion as the particles have more kinetic energy at higher temperatures
• surface area affects diffusion as the larger the surface area the the faster the rate of diffusion and the smaller the surface area the slower the rate of diffusion
• distance affects rate of diffusion as the shorter the distance the faster diffusion takes place
• Concentration gradient affects diffusion as the concentration gradient is the difference in concentration between the two places
• Osmosis is the movement of water from a region of high concentration to a region of low concentration across a partially permeable membrane