IGCSE Biology (0610) — May–June 2025, Paper 23
40 questions · every question answerable online with instant point-by-point AI marking against the official mark scheme.
Start with Question 1 →The diagram shows an aquatic plant in light. [Diagram: a test tube of water containing an aquatic plant at the bottom; light is directed at the plant from the left (arrow labelled…
Answer this question and get it marked →The diagrams show four organisms. Which organism is a prokaryote? [Diagrams (not to scale): A is a rod-shaped cell with a cell wall and coiled circular DNA but no nucleus; B is an…
Answer this question and get it marked →What happens when plant cells are placed in a sugar solution that has a lower water potential than the cytoplasm of the cells? A The cells gain water and become flaccid. B The…
Answer this question and get it marked →In a DNA molecule, bonds between pairs of bases hold two strands together. High temperatures can break these bonds to form two single strands of DNA. The base pair C and G is held…
Answer this question and get it marked →The diagram shows a process involving an enzyme in the human stomach. [Diagram: a Pac-Man-shaped enzyme (with a notch) combines with a triangular substrate labelled 1; an…
Answer this question and get it marked →What is the balanced chemical equation for photosynthesis? A 3CO2 + 3H2O - C6H12O6 + 3O2 B 6CO2 + 6O2 - C6H12O6 + 6H2O C 6CO2 + 6H2O - C6H12O6 + 6O2 D 6CO2 + 6H2O - 6C6H12O6 + 6O2
Answer this question and get it marked →A potato was removed from a potato plant. A 5 g cube of potato was cut and put into a beaker of distilled water. What is the most likely mass of the cube of potato after two…
Answer this question and get it marked →The diagram shows the direction of net movement of two substances across a human placenta. [Diagram: a central shaded bar represents the placenta, with tissue P on the left and…
Answer this question and get it marked →The diagram shows part of a cross-section of a leaf. Which structure is a palisade mesophyll cell? [Diagram: a labelled leaf cross-section. A points to a cell in the upper…
Answer this question and get it marked →A person has swollen, bleeding gums and slow wound healing. This could be caused by a lack of which nutrient in a diet? A calcium B fibre C iron D vitamin C
Answer this question and get it marked →Digested food molecules move into the cells of the body where they are used and become part of the cells. What is this a definition of? A absorption B assimilation C digestion D…
Answer this question and get it marked →The diagram shows part of the human digestive system. In which part does protein digestion begin? [Diagram: part of the human alimentary canal. A points to the oesophagus; B…
Answer this question and get it marked →The diagrams show cross-sections of a leaf, a root and a stem. [Diagrams (not to scale): leaf cross-section with 1 pointing to the upper tissue and 2 pointing to a vascular bundle…
Answer this question and get it marked →Which structures in humans and in plants normally carry amino acids? arteries phloem --- --- --- A yes yes B yes no C no yes D no no
Answer this question and get it marked →Through which pathway does blood leave the heart? A through arteries from the atria B through arteries from the ventricles C through veins from the atria D through veins from the…
Answer this question and get it marked →The photomicrograph shows some blood cells. [Photomicrograph: several pale, round, biconcave red blood cells (no nucleus) and one larger cell labelled X with a lobed (multi-lobed)…
Answer this question and get it marked →Which row shows the effects of cholera on the human body? movement of chloride ions effect of a build-up of chloride ions on water potential effect on volume of water leaving the…
Answer this question and get it marked →The plotted points, 1 and 2, on the graph show two different types of structure in the breathing system of a human. [Graph: y-axis is "relative diameter of lumen", x-axis is…
Answer this question and get it marked →Which process in plants uses energy from respiration? A cell division B osmosis C photosynthesis D transpiration
Answer this question and get it marked →Which sequence of statements explains the build-up and removal of an oxygen debt? 1 Anaerobic respiration occurs in muscles during vigorous exercise. 2 Faster and deeper breathing…
Answer this question and get it marked →What is filtered out of the blood in the glomerulus and into the nephron? glucose urea --- --- --- A yes yes B yes no C no yes D no no
Answer this question and get it marked →What can be broken down to form urea? A amino acids B fatty acids C sugars D vitamins
Answer this question and get it marked →The diagram shows a simple reflex arc. [Diagram: a hand (with a receptor in the skin) connected to the spinal cord. Neurone P runs from the receptor in the skin toward the spinal…
Answer this question and get it marked →The diagram shows a cross-section of an eye. [Diagram: cross-section of an eye. E points to the ciliary muscle (in the ciliary body); F points to the lens; G points to the…
Answer this question and get it marked →Which hormones increase the blood glucose concentration in humans? A adrenaline and glucagon B adrenaline and insulin C glucagon only D insulin only
Answer this question and get it marked →A shoot tip was placed on an agar block. Substances can diffuse through agar. Light was shone on the shoot tip from one direction. [Diagram: a shoot tip sits on an agar block that…
Answer this question and get it marked →The diagram shows reproduction in a potato plant. Potato X was planted into the ground and a plant grew from it. The plant then produced potato Y. [Diagram: a potato plant with…
Answer this question and get it marked →Which statement about pollination is correct? A Self-pollination increases the ability of the population to respond to changes in the environment by increasing variation. B…
Answer this question and get it marked →The graph shows changes in the thickness of the lining of the uterus wall during a menstrual cycle. [Graph: y-axis is "thickness of uterus wall lining", x-axis is "day of the…
Answer this question and get it marked →Which name is given to different versions of a gene? A allele B chromosome C length of DNA D protein
Answer this question and get it marked →The diagram shows the cells of a mammalian embryo shortly after fertilisation. [Diagram: a cluster of several similar cells (a ball of cells), each containing a nucleus, showing…
Answer this question and get it marked →The diagram shows the inheritance, in one family, of a sex-linked recessive disease. [Pedigree diagram with key: circle = female, square = male; shaded = affected, unshaded =…
Answer this question and get it marked →Which row describes continuous and discontinuous variation? continuous variation discontinuous variation --- --- --- A body mass in animals is an example caused by genes and the…
Answer this question and get it marked →Which statements describe an adaptive feature in an organism? 1 It helps an organism to survive and reproduce in its environment. 2 It always shows continuous variation. 3 It is…
Answer this question and get it marked →The graph shows the change in the percentage of bacteria resistant to antibiotic X. [Graph: y-axis is "percentage of bacteria resistant to antibiotic X", x-axis is "time". The…
Answer this question and get it marked →The diagram shows the flow of energy, in units of energy, through a food chain. producers (1000 units) - primary consumers (100 units) - secondary consumers (10 units) - tertiary…
Answer this question and get it marked →Which process in the nitrogen cycle can be caused by lightning and bacteria? A deamination B denitrification C nitrification D nitrogen fixation
Answer this question and get it marked →Which phase in the population growth curve shows when death rates are higher than birth rates? [Graph: y-axis is "number of organisms", x-axis is "time". The sigmoid (S-shaped)…
Answer this question and get it marked →What is a disadvantage of large-scale monocultures of crop plants? A a decrease in use of insecticides B a decrease in fossil fuel emissions C an increase in biodiversity D an…
Answer this question and get it marked →Some processes involved in the production of human insulin by genetic modification are listed. 1 insertion of the human insulin gene DNA into a cut bacterial plasmid 2 bacteria…
Answer this question and get it marked →