Movement Into and Out of Cells
170 questions· page 1 of 17
Molecules and ions can be moved into and out of cells by active transport.
Which statement about active transport is not correct?
Options
A Active transport takes place only in plants.
B Active transport moves molecules and ions against a concentration gradient.
C Active transport uses energy to move molecules and ions.
D Molecules and ions are moved across partially permeable membranes by active transport.
Frogs are amphibians and so have a partially permeable skin. They live in and near water such as lakes and marshes, where the water contains a low concentration of mineral ions. They absorb any water they need through their skin.
Biologists are concerned that frogs living near coasts will be endangered if global warming leads to a rise in sea level. Sea water contains a high concentration of mineral ions.
What would happen to the frogs if their habitat became flooded with sea water?
Options
A Water would move into the frog by osmosis.
B Mineral ions would move out of the frog by diffusion.
C Water would move into the frog by diffusion.
D Water would move out of the frog by osmosis.
Which combination of factors will result in the fastest rate of diffusion across a membrane?
Options
| surface area of the membrane | temperature | |
|---|---|---|
| A | small | low |
| B | small | high |
| C | large | high |
| D | large | low |
A leaf is taken from some pondweed (Elodea) and placed on a microscope slide.
A drop of sodium chloride solution is added.
The cells of the leaf are then viewed through a light microscope.
Which statement describes the cells viewed through the microscope?
Options
A The cells are plasmolysed because water has moved in by osmosis.
B The cells are plasmolysed because water has moved out by osmosis.
C The cells are turgid because water has moved in by osmosis.
D The cells are turgid because water has moved out by osmosis.
What is a function of a plant cell wall?
Options
A to control loss of ions from the cell
B to control movement of glucose into the cell
C to prevent evaporation of water from the cell
D to prevent the cell bursting when water enters
Contact lenses are placed on the surface of the eye to correct problems with vision.
One type of contact lens is partially permeable and is normally stored in a sterile sodium chloride solution.
The sodium chloride solution has the same concentration as the fluid that covers the surface of the eye.
A person makes a mistake and stores their contact lenses in distilled water rather than sodium chloride solution.
They then place a contact lens on the surface of their eye.
Which pair of statements describe what then happens?
- Water from the eye fluid enters the contact lens by osmosis.
- Water leaves the contact lens and enters the eye fluid by osmosis.
- The contact lens shrinks.
- The contact lens swells.
Options
A 1 and 3
B 1 and 4
C 2 and 3
D 2 and 4
Which process involves the movement of molecules against a concentration gradient?
Options
A active transport
B diffusion
C osmosis
D transpiration
Which processes use energy obtained from respiration?
- contraction of intercostal muscles during breathing
- nitrate ions entering a root hair cell against the concentration gradient
- oxygen moving from the lungs into blood capillaries
- production of antibodies by lymphocytes
- water entering a bacterial cell by osmosis
Options
A 1, 2 and 3
B 1, 2 and 4
C 2, 3 and 4
D 3, 4 and 5
Which statement about osmosis is correct?
Options
A An animal cell immersed in distilled water will shrink.
B A plant cell immersed in distilled water will become flaccid.
C A plant cell immersed in a strong sodium chloride solution will become turgid.
D A plant cell immersed in a strong sodium chloride solution will become plasmolysed.
When animal cells and plant cells are placed in distilled water, the animal cells burst but the plant cells do not.
Which statement explains this difference?
Options
A Animal cells do not contain starch grains, so there is no osmosis.
B Only plant cells have a permanent vacuole which stores water.
C Plant cells have a stronger cell membrane than animal cells.
D The cell wall of plant cells resists turgor pressure.