Quiz 3.A - Answers
1) What is diffusion?
Diffusion is the net movement of particles from a place where there is a high concentration of them to a place where there is a lower concentration of them
2) What influences the rate of diffusion?
Temperature, concentration gradient and surfaces area to volume ratio
3) Do the particles in diffusion move with or against the concentration gradient?
With
4) What is osmosis?
Osmosis is the net movement of water molecules through a partially permeable membrane from a dilute solution to a more concentrated solution
5) What is a partially permeable membrane?
Partially permeable means that some substances are let through and other substances are not let through. For example, water is able to pass through the membrane in visking tubing, but sucrose is unable to pass through the membrane.
6) What does water potential mean?
Water potential refers to how free the water molecules are to move
7) Is the water potential of pure water greater or less than the water potential of a sucrose solution?
Greater. The water potential of pure water is greater than the water potential of a sucrose solution.
8) What is active transport?
Active transport moves in substances against a concentration gradient (which means that a substance moves from a place where there is a low concentration to a place where there is a higher concentration of that substance)
9) Do the particles in active transport move with or against the concentration gradient?
Against
10) Out of diffusion, osmosis and active transport, which one(s) use energy? And what type of energy is used?
ATP require energy and it requires ATP. Diffusion and osmosis do not require any energy.
11) What influences the rate of osmosis?
Temperature, concentration gradient, surfaces area to volume ratio and water potential
12) Where does active transport occur?
The small intestine
13) Fill in the gaps:
The alveoli are responsible for gas exchange. Oxygen _______ from the alveoli into the blood stream/ capillary, and carbon dioxide __________ from the blood stream /capillary into the alveoli.
Diffuses, diffuses
Diffusion is the net movement of particles from a place where there is a high concentration of them to a place where there is a lower concentration of them
2) What influences the rate of diffusion?
Temperature, concentration gradient and surfaces area to volume ratio
3) Do the particles in diffusion move with or against the concentration gradient?
With
4) What is osmosis?
Osmosis is the net movement of water molecules through a partially permeable membrane from a dilute solution to a more concentrated solution
5) What is a partially permeable membrane?
Partially permeable means that some substances are let through and other substances are not let through. For example, water is able to pass through the membrane in visking tubing, but sucrose is unable to pass through the membrane.
6) What does water potential mean?
Water potential refers to how free the water molecules are to move
7) Is the water potential of pure water greater or less than the water potential of a sucrose solution?
Greater. The water potential of pure water is greater than the water potential of a sucrose solution.
8) What is active transport?
Active transport moves in substances against a concentration gradient (which means that a substance moves from a place where there is a low concentration to a place where there is a higher concentration of that substance)
9) Do the particles in active transport move with or against the concentration gradient?
Against
10) Out of diffusion, osmosis and active transport, which one(s) use energy? And what type of energy is used?
ATP require energy and it requires ATP. Diffusion and osmosis do not require any energy.
11) What influences the rate of osmosis?
Temperature, concentration gradient, surfaces area to volume ratio and water potential
12) Where does active transport occur?
The small intestine
13) Fill in the gaps:
The alveoli are responsible for gas exchange. Oxygen _______ from the alveoli into the blood stream/ capillary, and carbon dioxide __________ from the blood stream /capillary into the alveoli.
Diffuses, diffuses