For an organism to function, substances must move into and out of cells. Three processes contribute to this movement - diffusion, osmosis and active transport.
What will happen if a spray of perfume is released into one corner of a room?
Particles of the perfume will move by osmosis but remain most concentrated in the corner where they were sprayed
Particles of the perfume will diffuse until they are spread evenly through the room
The movement of the particles of the perfume will be limited so they will remain concentrated in the corner of the room
Which factor will decrease the rate of diffusion across a membrane?
Increasing the surface area of the membrane
Increasing the differences in concentration outside and inside the membrane
Decreasing the temperature
What is the surface area to volume ratio of a cube with sides 7 cm?
What happens to red blood cells when they are placed in water?
They shrivel as water is lost by osmosis
The cells are unchanged as water moves in and out by osmosis
The cells swell up and burst
Which of the following organisms has the largest surface area to volume ratio?
Why does a mouse experience more problems with heat loss than an elephant?
The mouse is less active than the elephant
The mouse does not eat as much food as the elephant, so will not generate as much heat by respiration
The mouse has a larger surface area to volume ratio
Which of the following is a correct statement about osmosis?
Water moves from a concentrated solution to a dilute solution across a partially permeable membrane
Water moves from a region of high concentration to a low concentration across a partially permeable membrane
Water and sugar move from a region of high concentration to a low concentration by osmosis
The mass of a cylinder of beetroot was 2.5 g. If its final mass in an osmosis experiment was 2.7 g, what was the increase in mass in per cent?
If the decrease in mass of a cylinder of beetroot was 0.62 g in 48 minutes, what was the rate of water loss?
0.013 g h-1
0.78 g h-1
29.76 g h-1
Which of the following involves passive movement?
The movement of glucose through the gut wall into the blood
The movement of carbon dioxide into a leaf
The movement of mineral ions into a plant root hair cell