Identify a type of molecular movement which is highly selective and requires special membrane proteins, but does not require energy.
The type of molecular movement which is highly selective and requires special membrane proteins but does not require energy is passive diffusion.
Facilitated diffusion facilitates movement of molecules or ions which are larger in size, polar or charged to move across a cell membrane which is selectively permeable. It uses membrane proteins like carrier and channel proteins for facilitating the movement of the substances along the concentration gradient.
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Halophytes may show cell pressure very much higher than atmospheric pressure. Explain how this can happen?Biology - Exemplar
Define Uniport, Symport and Antiport. Do they require energy?
I) Uniport: When a single substance moves in a single direction across a cell membrane, it is called uniport.
II) Antiport: When two substances move in the opposite direction across a cell membrane, it is called antiport.
III) Symport: When two substances move in the same direction across a cell membrane, it is called symport.
Biology - Exemplar
Comment on the experimental setup
a. What does the setup demonstrate?
b. What will happen to the level of water if a blower is placed close to setup.
c. Will the mercury level fluctuate (go up/down) if phenyl mercuric acetate is sprayed on leaves?
Biology - Exemplar
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How is facilitated diffusion different from diffusion?Biology - Exemplar
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