Q1.
The diagram shows a cell.
 
(a)     (i)      Use words from the box to name the structures labelled A and B .

	cell membrane	chloroplast	cytoplasm	nucleus	
A ___________________________
B ___________________________
(2)
(ii)     The cell in the diagram is an animal cell.
How can you tell it is an animal cell and not a plant cell?
Give two reasons.
1. ____________________________________________________________
______________________________________________________________
2. ____________________________________________________________
______________________________________________________________
(2)
(b)     Oxygen will diffuse into the cell in the diagram.
Why?
Use information from the diagram.
___________________________________________________________________
___________________________________________________________________
(1)
(c)     The cell shown in the diagram is usually found with similar cells.
Draw a ring around the correct answer to complete the sentence.

	 	an organ.	
 
	Scientists call a group of similar cells	a system.	
 
	 	a tissue.	
(1)
(Total 6 marks)
Q2.
Cells, tissues and organs are adapted to take in different substances and get rid of different substances.
The table shows the concentration of four ions outside cells and inside cells.
 
Ion	Concentration outside cells in mmol per dm3	Concentration inside cells in mmol per dm3	
Sodium	140	    9	
Potassium	    7	138	
Calcium	    2	  27	
Chloride	118	    3	
(a)     Use information from the table above to complete the following sentences.
Sodium ions will move into cells by the process
of __________________________________ .
Potassium ions will move into cells by the process
of __________________________________ .
(2)
(b)     Some students investigated the effect of the different concentrations of sugar in four drinks, A, B, C and D, on the movement of water across a partially permeable membrane.
The students:
•        made four bags from artificial partially permeable membrane
•        put equal volumes of 5% sugar solution in each bag
•        weighed each bag containing the sugar solution
•        placed one bag in each of the drinks, A, B, C and D
•        after 20 minutes removed the bags containing the sugar solution and weighed them again.
The diagram below shows how they set up the investigation.
 
(i)      The bag in drink A got heavier after 20 minutes.
Explain why.
______________________________________________________________
______________________________________________________________
______________________________________________________________
______________________________________________________________
(3)
(ii)     In which drink, A, B, C or D, would you expect the bag to show the smallest change in mass?
 
Tick (✔) one box.	 	
 
A		 	B		 	C		 	D		
(1)
(iii)     Explain why you think the bag you chose in part (b)(ii) would show the smallest change.
______________________________________________________________
______________________________________________________________
______________________________________________________________
______________________________________________________________
(2)
(Total 8 marks)
Q3.
(a)     The concentration of sulfate ions was measured in the roots of barley plants and in the water in the surrounding soil.
          The table shows the results.
 
 	Concentration of sulfate ions in mmol per dm3	
Roots of barley plants	1.4	
Soil	0.15	
          Is it possible for the barley roots to take up sulfate ions from the soil by diffusion?
          Draw a ring around your answer. Yes / No
          Explain your answer.
___________________________________________________________________
___________________________________________________________________
___________________________________________________________________
___________________________________________________________________
(2)
(b)     Some scientists investigated the amounts of sulfate ions taken up by barley roots in the presence of oxygen and when no oxygen was present.
          The graph below shows the results.
 
(i)      The graph shows that the rate of sulfate ion uptake between 100 and 200 minutes, without oxygen, was 0.4 arbitrary units per minute.
         The rate of sulfate ion uptake between 100 and 200 minutes, with oxygen, was greater.
         How much greater was it? Show clearly how you work out your answer.
______________________________________________________________
______________________________________________________________
______________________________________________________________
Answer __________ arbitrary units
(2)
(ii)     The barley roots were able to take up more sulfate ions with oxygen than without oxygen.
         Explain how.
______________________________________________________________
______________________________________________________________
______________________________________________________________
______________________________________________________________
______________________________________________________________
______________________________________________________________
(3)
(Total 7 marks)

Mark schemes
Q1.
(a)     (i)      A = nucleus
1
B = (cell) membrane
1
(ii)     any two from:
ignore shape
•        no (cell) wall
•        no (large / permanent) vacuole
•        no chloroplasts / chlorophyll
2
(b)     because high to low oxygen / concentration or down gradient
allow ‘more / a lot of oxygen molecules outside’
ignore along / across gradient
1
(c)     a tissue
1
[6]
Q2.
(a)     diffusion
1
active transport
1
this order only
(b)     (i)      concentration (of sugar) in the bag was higher (than in the drink)
allow concentration (of sugar) in the drink was lower (than in the bag)
or
higher concentration of water outside the bag or in the drink / boiling tube
allow higher water potential outside the bag or lower water potential inside the bag
1
(so) water moved in (to the tubing)
allow water moves down its concentration gradient
do not allow sugar moving
1
by osmosis
allow diffusion (of water)
do not allow sugar moving by osmosis or water moving by active transport
1
(ii)     B
1
(iii)     close(st) to the concentration in the bag or to 5%
allow small(est) diffusion gradient or close(st) to an equilibrium
1
(so rate of) diffusion / osmosis is slow
allow (so) less water moves in (to the bag)
ignore ref. to sugar
1
[8]
Q3.
(a)     No
no mark
if yes max 1 for correct statement
          diffusion is down the concentration gradient
accept by diffusion ions would leave the root
1
          to enter must go up / against the concentration gradient
or concentration higher in the root
or concentration lower in the soil
1
(b)     (i)      0.9 or 3.25
for correct answer with or without working
if answer incorrect 1.3 or their rate – 0.4 gains 1 mark
or 130 – 40 or 90 gains 1 mark
2
(ii)     (uptake) by active transport
1
         requires energy
         more energy from aerobic respiration
1
         or
         more energy when oxygen is present
1
[7]