Active transport: pumps and vesicles
Grade 9 Science Worksheet
Circle the best answer.
Read this first
Use this
Membrane drawing (model, not to scale). A bilayer: a top row of round heads, tails meeting in the middle, and a bottom row of round heads, with watery fluid outside the cell above and watery fluid inside the cell below. Letter P points to a sodium-potassium pump across the bilayer, with 1 ATP label beside it. A note says the pump runs 4 cycles and uses 1 ATP in each cycle.
Ari’s drawing shows a sodium-potassium pump that runs 4 cycles and uses 1 ATP in each cycle. How many ATP are used, and how many ions move?
- 12 ATP used, 12 sodium ions out, 8 potassium ions in
- 4 ATP used, 12 sodium ions out, 12 potassium ions in
- 4 ATP used, 12 sodium ions out, 8 potassium ions in
- 4 ATP used, 8 sodium ions out, 12 potassium ions in
A sodium-potassium pump in Bo’s drawing has moved 12 potassium ions into the cell, using 1 ATP per cycle. How many sodium ions has it moved out, and how many ATP has it used?
- 18 sodium ions out, using 6 ATP
- 8 sodium ions out, using 4 ATP
- 18 sodium ions out, using 12 ATP
- 12 sodium ions out, using 6 ATP
Use the table
Lab card (model data), not to scale. Counts before the sodium-potassium pump P, which sits in a bilayer, runs.
Ion Outside the cell Inside the cell sodium ions 40 15 potassium ions 10 30 A note says pump P then runs 3 cycles. The card is read about only: a teacher counted the ions, and no one handled anything.
Esme reads the counts before a pump runs 3 cycles. What are the counts after the 3 cycles?
- Sodium: 49 outside, 6 inside; potassium: 4 outside, 36 inside
- Sodium: 43 outside, 12 inside; potassium: 7 outside, 33 inside
- Sodium: 46 outside, 9 inside; potassium: 1 outside, 39 inside
- Sodium: 31 outside, 24 inside; potassium: 16 outside, 24 inside
Jun watches potassium ions move through protein P from outside (4 ions) to inside (20 ions), with an ATP label beside P. What kind of transport is this?
- Primary active transport, because the ions move down their gradient
- Secondary active transport, because the gradient does the work
- Primary active transport, because ATP powers the protein directly
- Facilitated diffusion, because a protein helps the ions cross
Use this
Membrane drawing (model, not to scale).
Luz’s drawing shows carrier H moving glucose from outside (30 molecules) to inside (10 molecules), with no ATP label. What kind of transport is this?
- Facilitated diffusion, because glucose moves down its gradient with no ATP
- Secondary active transport, because the carrier changes shape
- Primary active transport, because glucose moves down its gradient
- Primary active transport, because a carrier protein is used
Milo’s drawing shows a membrane folding around a large particle and engulfing it into a vesicle. Which process is this?
- Pinocytosis, which takes in a small drop of fluid
- Exocytosis, which brings a large particle into the cell
- Phagocytosis, which engulfs a large particle
- Receptor-mediated endocytosis, which binds one kind of substance
Receptor proteins on Noah’s cell membrane bind one kind of substance, and the membrane pinches in around it. Which process is this?
- Exocytosis, which takes in one specific substance
- Receptor-mediated endocytosis, which takes in one specific substance
- Phagocytosis, which engulfs a large particle of any kind
- Pinocytosis, which takes in a drop of fluid
Use this
Membrane drawing (model, not to scale). A bilayer: a top row of round heads, tails meeting in the middle, and a bottom row of round heads, with watery fluid outside the cell above and watery fluid inside the cell below. Letter P points to a sodium-potassium pump that faces the inside of the cell. 3 sodium ions are attached to it, 1 ATP has been split, and a phosphate group is attached to P. Outside the cell: 2 potassium ions.
Ren’s drawing shows a sodium-potassium pump after ATP has been split. What does the pump do next?
- It lets go of the 3 sodium ions inside the cell and takes up more
- It changes shape to face the outside and binds 3 potassium ions
- It changes shape to face the outside and lets go of the 3 sodium ions
- It stays facing the inside while the sodium ions slip out
Use this
Membrane drawing (model, not to scale). A bilayer: a top row of round heads, tails meeting in the middle, and a bottom row of round heads, with watery fluid outside the cell above and watery fluid inside the cell below. Letter P points to a sodium-potassium pump with an ATP label beside it. Outside the cell: 20 sodium ions and 20 potassium ions. Inside the cell: 20 sodium ions and 20 potassium ions. The pump then runs for many cycles with enough ATP.
Tala’s cell starts with equal counts on both sides, and pump P runs for many cycles with enough ATP. Which prediction fits?
- More sodium ions outside and more potassium ions inside
- The same number of each ion on both sides, because pumps even them out
- More sodium ions inside and more potassium ions outside
- More of both kinds of ion outside, because pumps move ions out
Use this
Membrane drawing (model, not to scale). A bilayer: a top row of round heads, tails meeting in the middle, and a bottom row of round heads, with watery fluid outside the cell above and watery fluid inside the cell below. Letter G points to a protein across the bilayer that carries sodium ions and glucose molecules into the cell together; no ATP label is beside G. Outside the cell: 60 sodium ions and 10 glucose molecules. Inside the cell: 8 sodium ions and 25 glucose molecules.
Zee’s drawing shows protein G open, with sodium ions and glucose outside. Predict what happens to the glucose molecules at G.
- They move in, and G uses ATP directly to carry them
- They stop, since glucose would have to move toward more glucose
- They keep moving in, carried by sodium ions moving down their gradient
- They move in with no energy source, since carriers use no energy