BIOLOGY PAPER 2 Questions with
complete solution 2025
1.2 = 0.155
1.3 = 180
3.5 = 0.4 and 39.6
6.5 = 48%
7.5 = 0.60 - correct answers MATHS
1.2
1.3
3.5
6.5 - HWE
7.5
-Colonisation by pioneer species
-Pioneer species change the environment factors
-Environment becomes less hostile for other or new species
-Increases biodiversity
to climax community - correct answers 1.1 - Describe and explain how
succession occurs
-Change in sequence of amino acids
-Change in hydrogen/ionic/disulphide bonds
-Alters tertiary structure - correct answers 2.1 - Explain how a single base
substitution causes a change in the structure of this polypeptide.
, -Produce healthy red blood cells
-No faulty red blood cells produced
-Stem/marrow cells continuously divide - correct answers 2.2 - Use this
information to explain how HSCT is an effective long-term treatment for SCD.
FOR GENE THERAPY
-No destruction of bone marrow
-Donors are not required
-Less chance of rejection
AGAINST GENE THERAPY
-Sickle red blood cells still produced
-Long-term effect not know - correct answers 2.3 - Evaluate conclusion -
method of gene therapy will be a more effective long-term treatment for SCD
than HSCT.
-Tip produces IAA
-Affects concentration of IAA
-Mitosis/division occurs in shoot tips
-Affects shoot length - correct answers 3.1 - Explain why the student removed
the shoot tip from each seedling.
For respiration provides ATP for growth - correct answers 3.2 - Explain why
the student added glucose solution to each Petri dish.
To prevent evaporation which alters concentration of IAA solution - correct
answers 3.3 - Explain why the lids were kept on the Petri dishes
complete solution 2025
1.2 = 0.155
1.3 = 180
3.5 = 0.4 and 39.6
6.5 = 48%
7.5 = 0.60 - correct answers MATHS
1.2
1.3
3.5
6.5 - HWE
7.5
-Colonisation by pioneer species
-Pioneer species change the environment factors
-Environment becomes less hostile for other or new species
-Increases biodiversity
to climax community - correct answers 1.1 - Describe and explain how
succession occurs
-Change in sequence of amino acids
-Change in hydrogen/ionic/disulphide bonds
-Alters tertiary structure - correct answers 2.1 - Explain how a single base
substitution causes a change in the structure of this polypeptide.
, -Produce healthy red blood cells
-No faulty red blood cells produced
-Stem/marrow cells continuously divide - correct answers 2.2 - Use this
information to explain how HSCT is an effective long-term treatment for SCD.
FOR GENE THERAPY
-No destruction of bone marrow
-Donors are not required
-Less chance of rejection
AGAINST GENE THERAPY
-Sickle red blood cells still produced
-Long-term effect not know - correct answers 2.3 - Evaluate conclusion -
method of gene therapy will be a more effective long-term treatment for SCD
than HSCT.
-Tip produces IAA
-Affects concentration of IAA
-Mitosis/division occurs in shoot tips
-Affects shoot length - correct answers 3.1 - Explain why the student removed
the shoot tip from each seedling.
For respiration provides ATP for growth - correct answers 3.2 - Explain why
the student added glucose solution to each Petri dish.
To prevent evaporation which alters concentration of IAA solution - correct
answers 3.3 - Explain why the lids were kept on the Petri dishes
