3.3 Active transport Flashcards
What is active transport?
Active transport is the movement of particles from a lower concentration to a higher concentration (against the concentration gradient) through a cell membrane, using energy from respiration.
What is the role of carrier proteins in active transport?
Carrier proteins are embedded in the cell membrane. They bind to specific molecules and move them through the membrane against the concentration gradient, using energy from respiration.
Why is active transport important for organisms?
Active transport allows organisms to move molecules or ions against a concentration gradient, which is important for processes like ion uptake by root hair cells or glucose absorption.
How does active transport work in root hair cells?
Root hair cells use active transport to take up ions like nitrates and magnesium from the soil. Since the concentration of these ions is higher inside the root hair cell, energy is needed to move them into the cell against the gradient.
How does active transport work in glucose uptake?
In the small intestine and kidney tubules, glucose is absorbed into cells against its concentration gradient through carrier proteins, using energy from respiration.
Can active transport move large particles into cells?
Yes, active transport can move large particles into cells via phagocytosis, where the cell membrane engulfs the particles (e.g., white blood cells engulfing bacteria).
