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Mathematics

Edexcel2024

5 2 2 2 (ii) Calculate a value for the enthalpy change of the Direct Ethanol Fuel Cell reaction, using your cycle. (1) Enthalpy change = kJ mol−1 ..............................................................

Question

Mathematics

Edexcel2024

2 (ii) Which variable affects the value of K ? p (1) A pressure B temperature C surface area of the catalyst D concentration of O (g)

Question

Mathematics

Edexcel2024

5 CO (g) −394

Question

Mathematics

Edexcel2024

Δ H r C H OH(l) + 3O (g) 3H O(l) + 2CO (g)

Question

Mathematics

Edexcel2024

2 p(cid:31)SO (cid:30)p(cid:31)O (cid:30)½ B 2 2 atm½ p(cid:31)SO (cid:30)

Question

Mathematics

Edexcel2024



Question

Mathematics

Edexcel2024

2 2 3 Equilibrium 2 H CO (aq)  H+(aq) + HCO−(aq)

Question

Mathematics

Edexcel2024

5 2 2 2 (a) Calculate the enthalpy change for the reaction using the mean bond enthalpy data. (3) Bond Mean bond enthalpy / kJ mol−1 C C 347 C H 413 C O 358 O H 464 O O 498 C O 805 Enthalpy change = kJ mol−1 .............................................................. *P76895A01228* DO NOT WRITE IN THIS AREA DO NOT WRITE IN THIS AREA DO NOT WRITE IN THIS AREA AERA SIHT NI ETIRW TON OD AERA SIHT NI ETIRW TON OD AERA SIHT NI ETIRW TON OD PMT (b) (i) Complete the enthalpy cycle for the overall reaction in the Direct Ethanol Fuel Cell. Include labels. (2) Substance Δ H / kJ mol−1 f C H OH(l) −277

Question

Biology

CAIE2024

(cid:44)(cid:1)(cid:1)(cid:1)(cid:1)(cid:9)(cid:1)(cid:1)(cid:1)(cid:1)(cid:1)(cid:1)(cid:2)(cid:4)(cid:44) (c) Concentrated urine contains a high concentration of solutes and a small volume of water. Different species of mammals vary in their ability to produce urine with a high solute concentration. Table 6.1 compares the ratio of the solute concentration of urine (U) to the solute concentration of blood plasma (P) in some mammal species. The habitats of the mammal species are also shown. Table 6.1 maximum ratio of solute concentration of urine mammal species habitat to solute concentration of blood plasma (U : P) beaver 1.7 : 1 rivers and lakes human 4.5 : 1 variable camel 8.0 : 1 desert rat 9.0 : 1 variable kangaroo rat 16.0 : 1 desert With reference to Table 6.1, suggest what the different values of U: P show about the ability of these mammal species to tolerate a shortage of water in their environment. ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... ............................................................................................................................................. [3] [Total: 11] © UCLES 2024 (cid:300) (cid:300) (cid:211) (cid:228) (cid:266) (cid:197) (cid:190) (cid:251) (cid:288) (cid:212) (cid:180) (cid:287) (cid:237) (cid:300) (cid:200) (cid:257) (cid:245) (cid:216) (cid:207) (cid:237) (cid:298) (cid:259) (cid:197) (cid:201) (cid:266) (cid:250) (cid:223) (cid:269) (cid:252) (cid:176) (cid:184) (cid:251) (cid:256) (cid:277) (cid:215) (cid:258) 9700/43/O/N/24 [Turn over (cid:293)(cid:293)(cid:261)(cid:213)(cid:245)(cid:181)(cid:197)(cid:213)(cid:229)(cid:229)(cid:261)(cid:261)(cid:261)(cid:213)(cid:197)(cid:245)(cid:213)(cid:213) NIGRAM SIHT NI ETIRW TON OD NIGRAM SIHT NI ETIRW TON OD NIGRAM SIHT NI ETIRW TON OD NIGRAM SIHT NI ETIRW TON OD NIGRAM SIHT NI ETIRW TON OD PMT * 0000800000014 *

Question

Mathematics

Edexcel2024

H O(l) −286

Question

Mathematics

Edexcel2024

2 3 (a) (i) What are the expression and the units for the equilibrium constant (K ) for p this reaction? (1) Expression Units p(cid:31)SO (cid:30) A 3 atm2 p(cid:31)SO (cid:30)p(cid:31)O (cid:30)½

Question

Physics

Edexcel2024

A length of wire has a non-uniform cross-sectional area. There is an electric current in the wire. Which of the following is not constant along the length of this wire? A electric current B electron charge C electron drift velocity D number of free electrons per unit volume (Total for Question 7 = 1 mark)

Question

Biology

CAIE2024

Question

Biology

CAIE2024

(cid:44)(cid:1)(cid:1)(cid:1)(cid:1)(cid:9)(cid:1)(cid:1)(cid:1)(cid:1)(cid:1)(cid:1)(cid:1)(cid:3)(cid:44)

Question

Physics

CAIE2024

(a) (i) State what is meant by the Avogadro constant. ........................................................................................................................................... ........................................................................................................................................... ..................................................................................................................................... [1] (ii) State the relationship between the Avogadro constant N , the molar gas constant R and A the Boltzmann constant k. [1] (b) Two samples X and Y of ideal gases are both at thermodynamic temperature T. Sample X has volume V and consists of N molecules, each of mass m. Sample Y has volume 2V and consists of 2N molecules, each of mass 2m. (i) Complete Table 3.1 by giving expressions, in terms of some or all of N, m, T, V and the constants in (a)(ii), for the quantities indicated. Table 3.1 sample X sample Y pressure amount of substance mean-square speed of molecules internal energy [4] (cid:300)(cid:209)(cid:266)(cid:190)(cid:288)(cid:180)(cid:237)(cid:200)(cid:245)(cid:207)(cid:298)(cid:197)(cid:266)(cid:222)(cid:251)(cid:181)(cid:256)(cid:215) © UCLES 2024 (cid:300)(cid:224)(cid:192)(cid:250)(cid:219)(cid:288)(cid:277)(cid:281)(cid:208)(cid:249)(cid:237)(cid:250)(cid:199)(cid:189)(cid:274)(cid:265)(cid:272)(cid:258) 9702/43/O/N/24 (cid:293)(cid:181)(cid:261)(cid:213)(cid:181)(cid:277)(cid:229)(cid:181)(cid:197)(cid:229)(cid:229)(cid:197)(cid:261)(cid:277)(cid:261)(cid:245)(cid:261)(cid:213) NIGRAM SIHT NI ETIRW TON OD NIGRAM SIHT NI ETIRW TON OD NIGRAM SIHT NI ETIRW TON OD NIGRAM SIHT NI ETIRW TON OD NIGRAM SIHT NI ETIRW TON OD PMT * 0000800000009 *

Question

Mathematics

Edexcel2024

3 3 (i) Write the expression for the acid dissociation constant, K , for carbonic acid. a State symbols are not required. (1) (ii) A blood sample taken from an individual was analysed. Calculate the pH of the blood sample. Use your expression for K and the values shown. a K for carbonic acid = 4.50 × 10−7 mol dm−3 a [HCO–] = 0.0240 mol dm−3 [H CO ] = 0.00200 mol dm−3

Question

Mathematics

Edexcel2024

3 3 (i) When a person exercises vigorously the concentration of carbon dioxide (aq) in the blood increases. Explain how this increase in the concentration of carbon dioxide affects the pH of the blood. Refer to the equilibria in your answer. No calculation is required. (2) .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... (ii) Explain how the carbonic acid–hydrogencarbonate buffer system in Equilibrium 2 acts to restore the pH of the blood after a person has exercised. (2) .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... (Total for Question 4 = 14 marks)

Question

Biology

CAIE2024

hours You must answer on the question paper. No additional materials are needed. INSTRUCTIONS ● Answer all questions. ● Use a black or dark blue pen. You may use an HB pencil for any diagrams or graphs. ● Write your name, centre number and candidate number in the boxes at the top of the page. ● Write your answer to each question in the space provided. ● Do not use an erasable pen or correction fluid. ● Do not write on any bar codes. ● You may use a calculator. ● You should show all your working and use appropriate units. INFORMATION ● The total mark for this paper is 100. ● The number of marks for each question or part question is shown in brackets [ ]. This document has 24 pages. [Turn over *3337887198* PMT * 0000800000001 * (cid:44)(cid:1)(cid:1)(cid:1)(cid:1)(cid:9)(cid:1)(cid:1)(cid:1)(cid:1)(cid:1)(cid:1)(cid:1)(cid:2)(cid:44) (cid:172)(cid:79)(cid:138)(cid:62)(cid:160)(cid:52)(cid:109)(cid:72)(cid:117)(cid:79)(cid:170)(cid:69)(cid:138)(cid:96)(cid:124)(cid:53)(cid:128)(cid:87) (cid:172)(cid:96)(cid:75)(cid:113)(cid:84)(cid:164)(cid:157)(cid:117)(cid:96)(cid:139)(cid:133)(cid:144)(cid:59)(cid:49)(cid:161)(cid:147)(cid:149)(cid:130) (cid:165)(cid:149)(cid:117)(cid:85)(cid:53)(cid:53)(cid:101)(cid:53)(cid:53)(cid:101)(cid:101)(cid:69)(cid:69)(cid:85)(cid:101)(cid:85)(cid:53)(cid:85) DC (PB/SG) 336398/4 © UCLES 2024 * 0000800000002 *

Question

Biology

CAIE2024

The leaves of many plants have stomata that show a regular daily rhythm of opening and closing over a period of 24 hours. (a) Explain why it is important for plants to open and close their stomata in a daily rhythm. ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... ............................................................................................................................................. [3] (b) Fig. 2.1 shows the results of an experiment to monitor this rhythm over three days and nights for the plant Arabidopsis thaliana. The percentage of open stomata is shown. Each day consisted of 14 hours of light (white bar) and each night consisted of 10 hours of darkness (black bar). 100 Key day open night stomata 50 / %

Question

Physics

CAIE2024

(cid:44)(cid:1)(cid:1)(cid:1)(cid:1)(cid:9)(cid:1)(cid:1)(cid:1)(cid:1)(cid:1)(cid:1)(cid:2)(cid:2)(cid:44) Fig. 4.2 shows the variation with T of the product pV for samples of the two gases, where p is the pressure of the gas and V is the volume of the gas.

Question

Biology

CAIE2024

(cid:44)(cid:1)(cid:1)(cid:1)(cid:1)(cid:9)(cid:1)(cid:1)(cid:1)(cid:1)(cid:1)(cid:1)(cid:1)(cid:6)(cid:44) ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... ............................................................................................................................................. [6] (c) The experiment was repeated with A. thaliana plants that were left in darkness from 14 to 96 hours. The results are shown in Fig. 2.2. 100 Key day open night stomata 50 / %

Question

Physics

CAIE2024

(a) (i) State what is meant by the Avogadro constant. ........................................................................................................................................... ........................................................................................................................................... ..................................................................................................................................... [1] (ii) State the relationship between the Avogadro constant N , the molar gas constant R and A the Boltzmann constant k. [1] (b) Two samples X and Y of ideal gases are both at thermodynamic temperature T. Sample X has volume V and consists of N molecules, each of mass m. Sample Y has volume 2V and consists of 2N molecules, each of mass 2m. (i) Complete Table 3.1 by giving expressions, in terms of some or all of N, m, T, V and the constants in (a)(ii), for the quantities indicated. Table 3.1 sample X sample Y pressure amount of substance mean-square speed of molecules internal energy [4] (cid:300)(cid:209)(cid:266)(cid:190)(cid:288)(cid:180)(cid:237)(cid:200)(cid:245)(cid:207)(cid:298)(cid:197)(cid:266)(cid:222)(cid:250)(cid:181)(cid:256)(cid:215) © UCLES 2024 (cid:300)(cid:223)(cid:285)(cid:250)(cid:211)(cid:286)(cid:298)(cid:239)(cid:206)(cid:268)(cid:241)(cid:287)(cid:277)(cid:287)(cid:251)(cid:298)(cid:276)(cid:258) 9702/41/O/N/24 (cid:293)(cid:213)(cid:197)(cid:213)(cid:245)(cid:181)(cid:261)(cid:245)(cid:229)(cid:197)(cid:245)(cid:261)(cid:197)(cid:213)(cid:229)(cid:277)(cid:197)(cid:213) NIGRAM SIHT NI ETIRW TON OD NIGRAM SIHT NI ETIRW TON OD NIGRAM SIHT NI ETIRW TON OD NIGRAM SIHT NI ETIRW TON OD NIGRAM SIHT NI ETIRW TON OD PMT * 0000800000009 *

Question

Physics

CAIE2024

(a) Define specific latent heat. ................................................................................................................................................... ................................................................................................................................................... ............................................................................................................................................. [2] (b) A dish containing 7.2 × 10–5 m3 of a substance rests on a laboratory bench. The substance is initially a liquid of density 710 kg m–3. Atmospheric pressure is 1.0 × 105 Pa. The liquid is heated at its boiling point so that it completely vaporises. The increase in the internal energy of the substance during this process is 17.6k J. The final volume of the vapour is 0.017 m3. (i) Show that the magnitude of the work done on the substance when it vaporises is 1.7 kJ. [2] (ii) Use the information in (b)(i) to calculate the thermal energy Q, in kJ, supplied to the substance to cause it to vaporise. Q = ..................................................... kJ [2] (iii) Use your answer in (b)(ii) to determine a value for the specific latent heat of vaporisation L , in kJ kg–1, of the substance. V L = .............................................. kJ kg–1 [2] V (cid:300)(cid:209)(cid:266)(cid:190)(cid:288)(cid:180)(cid:237)(cid:200)(cid:245)(cid:207)(cid:298)(cid:197)(cid:266)(cid:221)(cid:250)(cid:182)(cid:256)(cid:215) © UCLES 2024 (cid:300)(cid:236)(cid:186)(cid:251)(cid:206)(cid:299)(cid:271)(cid:244)(cid:207)(cid:243)(cid:243)(cid:199)(cid:295)(cid:298)(cid:182)(cid:193)(cid:280)(cid:258) 9702/42/O/N/24 (cid:293)(cid:181)(cid:229)(cid:277)(cid:245)(cid:277)(cid:293)(cid:245)(cid:261)(cid:261)(cid:293)(cid:261)(cid:197)(cid:181)(cid:229)(cid:181)(cid:277)(cid:213) NIGRAM SIHT NI ETIRW TON OD NIGRAM SIHT NI ETIRW TON OD NIGRAM SIHT NI ETIRW TON OD NIGRAM SIHT NI ETIRW TON OD NIGRAM SIHT NI ETIRW TON OD PMT * 0000800000009 *

Question

Mathematics

Edexcel2024

5 The equation for the second stage is shown. SO (g) + ½O (g)  SO (g) ΔH = −196 kJ mol−1

Question

Biology

CAIE2024

Lunularia cruciata is a primitive plant. Its body consists of a flattened sheet of photosynthetic tissue called a thallus. Fig. 5.1 shows L. cruciata with two different types of reproductive structure, labelled A and B, on its surface. A B Fig. 5.1 (a) Structures A and B and the thallus of L. cruciata are haploid. Explain what is meant by haploid. ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... ............................................................................................................................................. [2] (b) Structure A contains pale discs of tissue, C, that can germinate into new L. cruciata. The new plants that develop from C are genetically identical to the parent plant in Fig. 5.1. Structure B contains male sperm that are chemically attracted to swim to female eggs on a neighbouring parent plant. When the egg and sperm fuse, they form structure D. Structure D develops to produce spores that grow into new plants that are genetically different from the two parent plants. Identify which of the structures A, B, C and D are: associated with sexual reproduction ………………………………………… produced by mitosis ………………………………………… the site of meiosis ………………………………………… Each letter may be used once, more than once, or not at all. [3] (cid:300)(cid:209)(cid:266)(cid:190)(cid:288)(cid:180)(cid:237)(cid:200)(cid:245)(cid:207)(cid:298)(cid:197)(cid:266)(cid:221)(cid:250)(cid:184)(cid:254)(cid:215) © UCLES 2024 (cid:300)(cid:228)(cid:197)(cid:250)(cid:212)(cid:293)(cid:282)(cid:264)(cid:227)(cid:243)(cid:268)(cid:194)(cid:220)(cid:177)(cid:270)(cid:299)(cid:285)(cid:258) 9700/43/O/N/24 (cid:293)(cid:213)(cid:213)(cid:213)(cid:181)(cid:181)(cid:197)(cid:245)(cid:197)(cid:261)(cid:245)(cid:261)(cid:197)(cid:213)(cid:293)(cid:245)(cid:197)(cid:213) NIGRAM SIHT NI ETIRW TON OD NIGRAM SIHT NI ETIRW TON OD NIGRAM SIHT NI ETIRW TON OD NIGRAM SIHT NI ETIRW TON OD NIGRAM SIHT NI ETIRW TON OD PMT * 0000800000011 *

Question

Biology

CAIE2024

(cid:44)(cid:1)(cid:1)(cid:1)(cid:1)(cid:9)(cid:1)(cid:1)(cid:1)(cid:1)(cid:1)(cid:1)(cid:1)(cid:8)(cid:44) (b) A new hand‑held technological device shows the main type of respiratory substrate being used in the cells of a person. The device consists of a carbon dioxide sensor and air‑flow meter. The person inhales through the device for a fixed time and then exhales into it. The device calculates the respiratory quotient (RQ) value to show whether the cells are mainly respiring carbohydrates or lipids. (i) Explain how the device calculates the RQ value and how this shows whether the cells are mainly respiring carbohydrates or lipids. … ........................................................................................................................................ ........................................................................................................................................... … ........................................................................................................................................ … ........................................................................................................................................ … ........................................................................................................................................ … ........................................................................................................................................ … ........................................................................................................................................ ..................................................................................................................................... [4] (ii) State the difference in the relative energy values of carbohydrates and lipids as respiratory substrates, and explain the reasons for the difference. … ........................................................................................................................................ … ........................................................................................................................................ … ........................................................................................................................................ … ........................................................................................................................................ … ........................................................................................................................................ … .................................................................................................................................. [3] [Total: 11] © UCLES 2024 (cid:300) (cid:300) (cid:211) (cid:228) (cid:266) (cid:200) (cid:190) (cid:251) (cid:288) (cid:217) (cid:180) (cid:285) (cid:237) (cid:292) (cid:200) (cid:279) (cid:245) (cid:218) (cid:207) (cid:246) (cid:298) (cid:268) (cid:197) (cid:291) (cid:266) (cid:278) (cid:222) (cid:271) (cid:252) (cid:220) (cid:182) (cid:195) (cid:254) (cid:285) (cid:215) (cid:258) 9700/43/O/N/24 [Turn over (cid:293)(cid:181)(cid:293)(cid:277)(cid:245)(cid:181)(cid:293)(cid:213)(cid:261)(cid:277)(cid:261)(cid:197)(cid:261)(cid:245)(cid:197)(cid:245)(cid:293)(cid:213) NIGRAM SIHT NI ETIRW TON OD NIGRAM SIHT NI ETIRW TON OD NIGRAM SIHT NI ETIRW TON OD NIGRAM SIHT NI ETIRW TON OD NIGRAM SIHT NI ETIRW TON OD PMT * 0000800000008 *

Question

Mathematics

Edexcel2024

2 3 V O as the catalyst.

Question

Biology

CAIE2024

N = estimate of population size n = number of individuals captured in first sample

Question

Biology

CAIE2024

unmarked) captured in second sample m = number of marked individuals recaptured in

Question

Biology

CAIE2024

second sample population size = ......................................................... [2] [Total: 10] The boundaries and names shown, the designations used and the presentation of material on any maps contained in this question paper/insert do not imply official endorsement or acceptance by Cambridge Assessment International Education concerning the legal status of any country, territory, or area or any of its authorities, or of the delimitation of its frontiers or boundaries. Permission to reproduce items where third‑party owned material protected by copyright is included has been sought and cleared where possible. Every reasonable effort has been made by the publisher (UCLES) to trace copyright holders, but if any items requiring clearance have unwittingly been included, the publisher will be pleased to make amends at the earliest possible opportunity. To avoid the issue of disclosure of answer‑related information to candidates, all copyright acknowledgements are reproduced online in the Cambridge Assessment International Education Copyright Acknowledgements Booklet. This is produced for each series of examinations and is freely available to download at www.cambridgeinternational.org after the live examination series. Cambridge Assessment International Education is part of Cambridge Assessment. Cambridge Assessment is the brand name of the University of Cambridge Local Examinations Syndicate (UCLES), which is a department of the University of Cambridge. (cid:300)(cid:209)(cid:266)(cid:190)(cid:288)(cid:180)(cid:237)(cid:200)(cid:245)(cid:207)(cid:298)(cid:197)(cid:266)(cid:222)(cid:249)(cid:182)(cid:260)(cid:215) © UCLES 2024 (cid:300)(cid:228)(cid:200)(cid:252)(cid:215)(cid:291)(cid:261)(cid:292)(cid:215)(cid:249)(cid:245)(cid:174)(cid:252)(cid:274)(cid:271)(cid:203)(cid:285)(cid:258) 9700/43/O/N/24 (cid:293)(cid:245)(cid:277)(cid:213)(cid:245)(cid:245)(cid:229)(cid:245)(cid:197)(cid:197)(cid:213)(cid:261)(cid:197)(cid:181)(cid:293)(cid:245)(cid:245)(cid:213) NIGRAM SIHT NI ETIRW TON OD NIGRAM SIHT NI ETIRW TON OD NIGRAM SIHT NI ETIRW TON OD NIGRAM SIHT NI ETIRW TON OD NIGRAM SIHT NI ETIRW TON OD PMT

Question

Biology

CAIE2024

(cid:44)(cid:1)(cid:1)(cid:1)(cid:1)(cid:9)(cid:1)(cid:1)(cid:1)(cid:1)(cid:1)(cid:1)(cid:1)(cid:3)(cid:44)

Question

Biology

CAIE2024

(a) Fig. 1.1 is a diagram of part of a Bowman’s capsule and a glomerular capillary. A B Fig. 1.1 (i) Identify structures A and B. A ........................................................................................................................................ B ........................................................................................................................................ [2] (ii) The glomerular filtrate is produced in the Bowman’s capsule by the process of ultrafiltration. State the conditions required for ultrafiltration. ........................................................................................................................................... ........................................................................................................................................... ........................................................................................................................................... ........................................................................................................................................... ..................................................................................................................................... [2] (cid:300)(cid:205)(cid:266)(cid:190)(cid:288)(cid:180)(cid:237)(cid:200)(cid:245)(cid:207)(cid:298)(cid:197)(cid:266)(cid:221)(cid:250)(cid:183)(cid:254)(cid:215) © UCLES 2024 (cid:300)(cid:224)(cid:201)(cid:242)(cid:209)(cid:296)(cid:297)(cid:275)(cid:215)(cid:246)(cid:243)(cid:243)(cid:259)(cid:203)(cid:209)(cid:235)(cid:269)(cid:258) 9700/42/O/N/24 (cid:293)(cid:197)(cid:293)(cid:213)(cid:245)(cid:213)(cid:293)(cid:213)(cid:261)(cid:293)(cid:245)(cid:261)(cid:197)(cid:277)(cid:197)(cid:277)(cid:277)(cid:213) NIGRAM SIHT NI ETIRW TON OD NIGRAM SIHT NI ETIRW TON OD NIGRAM SIHT NI ETIRW TON OD NIGRAM SIHT NI ETIRW TON OD NIGRAM SIHT NI ETIRW TON OD PMT * 0000800000003 *

Question

Biology

CAIE2024

(cid:44)(cid:1)(cid:1)(cid:1)(cid:1)(cid:9)(cid:1)(cid:1)(cid:1)(cid:1)(cid:1)(cid:1)(cid:1)(cid:4)(cid:44) (b) As the newly formed glomerular filtrate passes along the proximal convoluted tubule, selective reabsorption takes place. The fluid remaining in the proximal convoluted tubule eventually forms urine. Table 1.1 lists three of the components of blood plasma that enter the glomerulus in a healthy person. Complete Table 1.1 by writing: • increased, if the component is present and is higher in concentration than in blood plasma • decreased, if the component is present and is lower in concentration than in blood plasma • same, if the component is present and is of the same concentration as blood plasma • not present, if the component is absent. You may use each response once, more than once or not at all. Table 1.1 component of blood plasma component in newly component in urine entering glomerulus formed glomerular filtrate glucose large plasma proteins urea [3] (c) Sweating during exercise can lead to a response in the posterior pituitary gland and in the kidney. State the response to sweating that occurs in the posterior pituitary gland and the response that occurs in the kidney. ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... ............................................................................................................................................. [2] [Total: 9] © UCLES 2024 (cid:300) (cid:300) (cid:207) (cid:224) (cid:266) (cid:202) (cid:190) (cid:241) (cid:288) (cid:217) (cid:180) (cid:290) (cid:237) (cid:293) (cid:200) (cid:291) (cid:245) (cid:226) (cid:207) (cid:260) (cid:298) (cid:254) (cid:197) (cid:182) (cid:266) (cid:215) (cid:221) (cid:179) (cid:252) (cid:261) (cid:183) (cid:235) (cid:254) (cid:285) (cid:215) (cid:258) 9700/42/O/N/24 [Turn over (cid:293)(cid:197)(cid:277)(cid:277)(cid:181)(cid:181)(cid:261)(cid:181)(cid:277)(cid:277)(cid:229)(cid:261)(cid:197)(cid:245)(cid:229)(cid:213)(cid:261)(cid:213) NIGRAM SIHT NI ETIRW TON OD NIGRAM SIHT NI ETIRW TON OD NIGRAM SIHT NI ETIRW TON OD NIGRAM SIHT NI ETIRW TON OD NIGRAM SIHT NI ETIRW TON OD PMT * 0000800000004 *

Question

Biology

CAIE2024

Several different processes can affect allele frequencies in populations. (a) Outline the processes that may affect allele frequencies in wildlife populations. ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... ............................................................................................................................................. [6] (b) The process of selective breeding changes allele frequencies in a population. Plant breeders use selective breeding to improve crop plants such as maize. Explain how selective breeding can be used to obtain a variety of maize where the plants are vigorous and of uniform height. ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... ............................................................................................................................................. [3] [Total: 9] (cid:300)(cid:205)(cid:266)(cid:190)(cid:288)(cid:180)(cid:237)(cid:200)(cid:245)(cid:207)(cid:298)(cid:197)(cid:266)(cid:223)(cid:250)(cid:183)(cid:256)(cid:215) © UCLES 2024 (cid:300)(cid:224)(cid:202)(cid:244)(cid:217)(cid:300)(cid:279)(cid:294)(cid:213)(cid:254)(cid:261)(cid:173)(cid:245)(cid:271)(cid:231)(cid:187)(cid:277)(cid:258) 9700/42/O/N/24 (cid:293)(cid:245)(cid:197)(cid:277)(cid:245)(cid:181)(cid:261)(cid:277)(cid:245)(cid:181)(cid:213)(cid:261)(cid:261)(cid:245)(cid:261)(cid:213)(cid:277)(cid:213) NIGRAM SIHT NI ETIRW TON OD NIGRAM SIHT NI ETIRW TON OD NIGRAM SIHT NI ETIRW TON OD NIGRAM SIHT NI ETIRW TON OD NIGRAM SIHT NI ETIRW TON OD PMT * 0000800000005 *

Question

Biology

CAIE2024

The treatment of many diseases has been improved by the use of genetic technology in medicine. (a) Explain what is meant by genetic engineering. ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... ............................................................................................................................................. [3] (b) (i) Leber Congenital Amaurosis (LCA) is an inherited eye disease. In LCA, the photoreceptor cells in the retina die at an early age. This causes impaired vision (reduced eyesight) in children, which can progress to blindness. Mutations in different genes cause different forms of LCA. One form of this disease, LCA2, is caused by a mutation in the RPE65 gene. Gene therapy has been used to treat LCA2. Outline how an inherited eye disease, such as LCA2, is treated with gene therapy. ........................................................................................................................................... ........................................................................................................................................... ........................................................................................................................................... ........................................................................................................................................... ........................................................................................................................................... ........................................................................................................................................... ........................................................................................................................................... ..................................................................................................................................... [3] (ii) Suggest why the eye is a suitable organ for gene therapy. ........................................................................................................................................... ..................................................................................................................................... [1] © UCLES 2024 (cid:300) (cid:300) (cid:207) (cid:224) (cid:266) (cid:201) (cid:190) (cid:243) (cid:288) (cid:209) (cid:180) (cid:286) (cid:237) (cid:283) (cid:200) (cid:278) (cid:245) (cid:228) (cid:207) (cid:252) (cid:298) (cid:252) (cid:197) (cid:252) (cid:266) (cid:225) (cid:223) (cid:295) (cid:252) (cid:243) (cid:183) (cid:187) (cid:256) (cid:293) (cid:215) (cid:258) 9700/42/O/N/24 [Turn over (cid:293)(cid:245)(cid:181)(cid:213)(cid:181)(cid:213)(cid:293)(cid:245)(cid:293)(cid:197)(cid:261)(cid:261)(cid:261)(cid:277)(cid:293)(cid:277)(cid:261)(cid:213) NIGRAM SIHT NI ETIRW TON OD NIGRAM SIHT NI ETIRW TON OD NIGRAM SIHT NI ETIRW TON OD NIGRAM SIHT NI ETIRW TON OD NIGRAM SIHT NI ETIRW TON OD PMT * 0000800000006 *

Question

Biology

CAIE2024

(cid:44)(cid:1)(cid:1)(cid:1)(cid:1)(cid:9)(cid:1)(cid:1)(cid:1)(cid:1)(cid:1)(cid:1)(cid:1)(cid:8)(cid:44) Key: eye not treated eye treated impaired 0.2 acuity

Question

Biology

CAIE2024

(a) Paper chromatography is a technique that can be used to separate and identify different chloroplast pigments. Describe how the results of paper chromatography can be used to identify chloroplast pigments. ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... ............................................................................................................................................. [3] (b) Carotene and xanthophyll are chloroplast pigments. Describe the role played by these pigments in photosynthesis. ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... ............................................................................................................................................. [3] (cid:300)(cid:205)(cid:266)(cid:190)(cid:288)(cid:180)(cid:237)(cid:200)(cid:245)(cid:207)(cid:298)(cid:197)(cid:266)(cid:222)(cid:249)(cid:181)(cid:260)(cid:215) © UCLES 2024 (cid:300)(cid:224)(cid:204)(cid:244)(cid:214)(cid:290)(cid:246)(cid:247)(cid:227)(cid:240)(cid:254)(cid:255)(cid:227)(cid:300)(cid:212)(cid:267)(cid:269)(cid:258) 9700/42/O/N/24 (cid:293)(cid:293)(cid:229)(cid:213)(cid:181)(cid:277)(cid:261)(cid:213)(cid:261)(cid:229)(cid:213)(cid:261)(cid:197)(cid:245)(cid:197)(cid:277)(cid:229)(cid:213) NIGRAM SIHT NI ETIRW TON OD NIGRAM SIHT NI ETIRW TON OD NIGRAM SIHT NI ETIRW TON OD NIGRAM SIHT NI ETIRW TON OD NIGRAM SIHT NI ETIRW TON OD PMT * 0000800000017 *

Question

Biology

CAIE2024

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Question

Biology

CAIE2024

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Biology

CAIE2024

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Biology

CAIE2024

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Question

Mathematics

Edexcel2024

This question is about the formation of ions. (a) Explain the trend in the values of the first electron affinities of the elements shown. (4) Element First electron affinity / kJ mol−1 chlorine −349 bromine −325 iodine −295 .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... (b) Which of these isoelectronic ions has the smallest ionic radius? (1) A S2− B Cl− C K+ D Ca2+ *P76895A0428* DO NOT WRITE IN THIS AREA DO NOT WRITE IN THIS AREA DO NOT WRITE IN THIS AREA AERA SIHT NI ETIRW TON OD AERA SIHT NI ETIRW TON OD AERA SIHT NI ETIRW TON OD PMT (c) Some series of successive ionisation energies in kJ mol−1 are shown. The letters do not refer to the symbols of the elements. Element Successive ionisation energies / kJ mol−1 A 578 1817 2745 11 578 14 831 B 653 1592 2987 4740 6686 C 738 1451 7733 10 541 13 629 D 1086 2353 4621 6223 37 832 (i) Which element in the table could be in Group 4? (1) A B C D (ii) Which element in the table could be described as an s-block element? (1) A B C D (Total for Question 2 = 7 marks)

Question

Mathematics

Edexcel2024

4 solution of concentration 0.0450 mol dm−3? The molar mass of K SO is 174.3 g mol−1.

Question

Mathematics

Edexcel2024

4 (1) A 1.96 g B 7.84 g C 19.6 g D 31.4 g (Total for Question 3 = 10 marks)

Question

Mathematics

Edexcel2024

Question

Mathematics

Edexcel2024

10 20 30 40 50 0 10 20 30 40 50 Volume of NaOH / cm3 Volume of NaOH / cm3 C D

Question

Mathematics

Edexcel2024

Question

Mathematics

Edexcel2024

10 20 30 40 50 0 10 20 30 40 50 Volume of NaOH / cm3 Volume of NaOH / cm3 *P76895A0828* DO NOT WRITE IN THIS AREA DO NOT WRITE IN THIS AREA DO NOT WRITE IN THIS AREA AERA SIHT NI ETIRW TON OD AERA SIHT NI ETIRW TON OD AERA SIHT NI ETIRW TON OD PMT (c) Some information about acids in aqueous solution is given. Comment on these pH values. No calculations are required. (4) pH of a solution of Name of acid Formula of acid

Question

Mathematics

Edexcel2024

4 propanoic acid CH CH COOH 2.94

Question

Mathematics

Edexcel2024

5 State symbols are not required. (2) (c) Which row of the table shows the correct colour of the solution and oxidation number of vanadium in the aqueous ions shown? (1) Oxidation number Aqueous ion Colour of solution of vanadium A VO+ yellow +3

Question