AS Biology 9700 | Oct/Nov 2025 Paper 12 | Past Paper Solution | Part 1 | ⁨@biologybyhr⁩

Описание: In this video, I solve and explain CAIE AS Level Biology 9700 Oct/Nov 2025 Paper 12 (Paper 1 MCQs) in a clear, step-by-step manner to help you score high in your exams.

PART 2    • AS Biology 9700 | Oct/Nov 2025 Paper 12 | ...  


This is Part 1 of the complete past paper solution series. Every MCQ is explained with detailed concepts so you understand the logic behind the correct answer, not just memorize it. This video is perfect for students preparing for AS Level Biology 9700 exams, revision before mocks, or final CIE board preparation.

0:00 - INTRO
0:33 - Q1 A student observed some cells using a microscope with an eyepiece graticule.
3:47 - Q2 Which structures will be present in a cell that causes cholera?
5 :18 - Q3 Which organelles have a partially permeable membrane?
6:42 - Q4 Mouse cells were grown in a dish containing a growth medium. Radioactively labelled amino acids were added to the growth medium. The table shows the time taken for the radioactively labelled amino acids to appear in three different organelles, R, S and T.
10:34 - Q5 The electron micrograph shows a section through a cell.
12:29 - Q6 A student carried out four tests for biological molecules. The observations are shown in the table. The diagrams show molecules or parts of molecules. Which pair is present in the solution?
15:42 - Q7 The diagram shows some relationships between features of carbohydrates. Which row correctly matches the carbohydrate with some of its features?
18:07 - Q8 The diagram shows a triglyceride molecule. Which statement is correct for the structure and function of this triglyceride?
21:43 - Q9 Enzyme P has been found in a tropical grass. The enzyme catalyses the hydrolysis of the fungal polysaccharide, chitin, into amino sugar It also inhibits the activity of an enzyme in locust guts which catalyses the digestion of amylose. Which row describes the actions of enzyme P?
23:30 - Q10 Which bonds between amino acids hold the shape of the secondary structure and also the tertiary structure of proteins?
24:52 - Q11 Resilin is a protein found in the wings of insects. It is an elastic, fibrous protein and scientists have suggested that it may have an important role in allowing the wings of an insect to fold and unfold without damage. Peptidyl transferase is an enzyme which catalyses the condensation of amino acids during translation to form resilin
25:45 - Q12 Collagen is a protein that helps to strengthen and increase the elasticity and hydration of the skin. Aging can lead to dry skin and the formation of wrinkles, due to the body producing less collagen. Which row is correct for the structure of collagen in the skin?
28:19 - Q13 What is the effect of an enzyme in an enzyme-catalysed reaction?
29:19 - Q14 How is the Michaelis–Menten constant (Km) used?
30:56 - Q15 Some students investigated the effect of pH on the rate of starch digestion by amylase at 20 °C.They added 2cm3of a 1% amylase solution and 1 cm3of pH4 buffer to a test-tube.They added 2cm3of a starch solution, containing 0.02 g of starch, to the test-tube.They measured the time taken for the starch to be digested (to disappear).
33:40 - Q16 Which statements are correct for a non-competitive inhibitor of enzyme action?
1 Increasing the concentration of the enzyme’s substrate will reduce its effect
36:12 - Q17 What can increase the fluidity of the cell surface membrane at low temperatures? 1 double bonds between carbon atoms in the fatty acid chains
38:30 - Q18 Which statements about the proteins and glycoproteins in cell surface membranes are correct? 1 They can allow cells to bond together to form tissues
40:00 - Q19 In an experiment, four different-sized cubes of colourless agar were placed into a blue dye. The time taken for each cube to turn blue was recorded.
43:12 - Q20 The stalk of a dandelion flower is a hollow tube called a scape. Pieces of the scape are cut as shown by the dotted lines and placed in sucrose solutions of different water potentials. Which diagram shows the piece that is placed in the sucrose solution with the highest water potential

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