2023 Cambridge IGCSE Biology (0610) Practice Paper with Answers

Which sequence of events occurs when a nerve impulse arrives at a synapse?

A person walks from a dimly-lit room into bright sunlight. Which row correctly describes the changes in the muscles of the iris and the size of the pupil?

Which row correctly identifies the roles of the amniotic fluid and the amniotic sac during pregnancy?

Which row correctly matches the hormone with its primary role during the human menstrual cycle?

Which structure in a villus is correctly matched with its primary function in absorption?

By which processes are glucose and water absorbed across the epithelial cells of the villi into the bloodstream?

Which statement represents a key reason for conserving endangered wild plant species?

Which conservation measure is most effective for maintaining sustainable marine fish stocks?

Which row correctly compares the features of the nervous system and the endocrine (hormonal) system?

What are the states of the ciliary muscles, suspensory ligaments, and lens shape when the eye focuses on a near object?

When a person enters a very cold room, how do the arterioles, shunt vessels, and hair erector muscles in the skin respond?

Which row correctly identifies substances that cross the placenta from the mother to the fetus, and substances that cross from the fetus to the mother?

What is the primary role of progesterone in the menstrual cycle?

Which statement correctly describes the function of structures within a villus in the small intestine?

Which of the following is a primary reason for conserving endangered species and maintaining biodiversity?

What is the correct sequence of events that occurs when fertilizer runoff enters a freshwater river?

A person moves from a dimly lit room into bright sunlight. Which row correctly describes the response of the iris muscles and the change in pupil size?

Adrenaline is released into the blood in response to a stressful situation. Which row shows the correct physiological changes that occur?

Which row correctly identifies the function of the placenta and the function of the amniotic fluid during pregnancy?

During the menstrual cycle, which hormone is responsible for stimulating the repair and growth of the uterus lining in the first half of the cycle, and which hormone maintains this lining in the second half of the cycle?

Which row correctly matches a structure in a villus of the small intestine with the substance it primarily absorbs and transports?

By which processes do glucose and water move from the lumen of the small intestine into the epithelial cells of the villi?

Which method is used to keep fish stocks at a sustainable level?

Which of the following is a key reason for conserving ecosystems and wild species?

What is the correct sequence of structures through which an impulse passes during a reflex action?

When a person moves from a dark room into a brightly lit room, which changes occur in the iris of the eye?

Which substances diffuse from the mother's blood to the fetus's blood across the placenta?

What is a function of progesterone during the menstrual cycle?

How do the structure and arrangement of villi in the ileum facilitate efficient absorption of digested food?

Which row correctly defines absorption and assimilation?

Which of the following is a primary reason for conserving endangered species?

What is a sustainable resource?

A person is sitting in a dimly lit room when suddenly a bright light is turned on. Which row correctly describes the responses of the iris muscles and the resulting change in pupil size?

Which statement about neurones and the pathway of a reflex arc is correct?

Which substances diffuse from the mother's blood to the fetus's blood across the placenta?

Where does fertilisation normally take place in the human female reproductive system, and where does implantation of the embryo occur?

The villi in the small intestine are highly adapted for absorption. Which row correctly matches a structural feature of a villus with its function?

Which region of the human alimentary canal absorbs the greatest volume of water on a daily basis?

Which human activity represents a sustainable method to conserve endangered marine fish populations?

Which statement describes a primary reason for conserving ecosystems and their biodiversity?

(a) State what is meant by a reflex action. [2] (b) Describe the pathway of a nerve impulse through a reflex arc when a person touches a hot object. [5] (c) Explain how an impulse is transmitted across a synapse. [6]

(a) Identify the specific site where fertilization normally occurs, and the site where the embryo implants in the female reproductive system. [2] (b) Describe the roles of follicle-stimulating hormone (FSH) and progesterone in the menstrual cycle. [4] (c) Explain how the structures of the placenta and the umbilical cord are adapted to allow the exchange of substances between mother and fetus. [7]

(a) State the name of the main region of the alimentary canal where water and digested food molecules are absorbed. [1] (b) Explain how the structure of a villus is adapted to maximize the absorption of nutrients. [6] (c) Distinguish between the functions of capillaries and lacteals in the villi during the transport of absorbed products. [3] (d) Explain how active transport is used in the absorption of glucose. [3]

(a) Define the term biodiversity. [2] (b) Discuss the ecological and economic reasons for conserving ecosystems and habitats. [6] (c) Explain how captive breeding programmes and seed banks are used as tools to prevent the extinction of endangered species. [5]

(a) Describe the changes that take place in the eye to focus on an object that moves closer to the viewer. [5] (b) Compare the functions of rod cells and cone cells in the retina. [4] (c) Describe the pupil reflex in bright light, explaining how this protects the eye from damage. [4]

(a) Define the term transpiration. [2] (b) Explain how the transpiration pull is generated and how water moves continuously up the xylem. [5] (c) Describe and explain how an increase in (i) wind speed and (ii) humidity affects the rate of transpiration. [6]

An investigation was carried out to determine the sensitivity of different areas of human skin using a two-point discrimination test. A paperclip was bent so that two points were a measured distance apart. The points were gently pressed onto the skin of a volunteer, who had their eyes closed. The volunteer was asked if they could feel one point or two points.

The test was repeated with the points at different distances apart to find the minimum distance at which the volunteer could consistently feel two separate points. This minimum distance is the 'two-point threshold'.

The test was performed on four skin areas: fingertip, palm, back of hand, and forearm. Three trials were carried out for each skin area.

(a) State the independent variable and the dependent variable in this investigation. [2]

(b) Suggest two variables that should be controlled to ensure the results are valid. [2]

(c) Suggest why the volunteer was required to have their eyes closed during the test. [1]

(d) Table 1.1 shows the results of this investigation.

Table 1.1
| Skin area tested | Trial 1 / mm | Trial 2 / mm | Trial 3 / mm | Mean / mm |
| :--- | :---: | :---: | :---: | :---: |
| Fingertip | 2.0 | 1.5 | 2.5 | **X** |
| Palm | 8.0 | 7.0 | 9.0 | 8.0 |
| Back of hand | 12.0 | 11.5 | 12.5 | 12.0 |
| Forearm | 35.0 | 38.0 | 32.0 | **Y** |

(i) Calculate the missing mean values **X** and **Y** in Table 1.1. [2]

(ii) Plot a bar chart on grid paper of the mean threshold distance against the skin area tested. [4]

(iii) State which skin area tested is the most sensitive and explain your choice. [2]

(e) Identify one possible source of error in this method and suggest an improvement to overcome it. [2]

(f) Hand-eye coordination can also be investigated using the ruler-drop test. Plan an investigation to determine whether the reaction time of a person changes after repeating the test several times (the effect of practice). [5]

A student set up an experiment to model absorption in the human digestive system. A Visking tubing bag containing a mixture of 10% starch solution and 5% glucose solution was placed into a beaker of distilled water.

After 30 minutes, samples were taken from the liquid inside the Visking tubing and from the water in the beaker. The samples were tested with iodine solution and with Benedict's solution.

(a) Table 2.1 is incomplete. Complete Table 2.1 by filling in the missing details (i) to (iv). [4]

Table 2.1
| Sample tested | Reagent used | Initial colour of reagent | Final colour of mixture | Conclusion |
| :--- | :--- | :--- | :--- | :--- |
| Liquid inside Visking tubing | Iodine solution | Orange-brown | **(i)** | Starch is present |
| Water in beaker | Iodine solution | Orange-brown | Orange-brown | **(ii)** |
| Liquid inside Visking tubing | Benedict's solution | **(iii)** | Brick-red | Reducing sugar is present |
| Water in beaker | Benedict's solution | Light blue | Brick-red | **(iv)** |

(b) Explain the results in terms of the properties of the Visking tubing and the molecules tested. [2]

(c) The student then investigated how the initial concentration of glucose inside the Visking tubing affected the rate of diffusion. The concentration of glucose in the water outside the tubing was measured after exactly 10 minutes. The results are shown in Table 2.2.

Table 2.2
| Initial glucose concentration inside tubing / % | Glucose concentration in surrounding water after 10 mins / mg per 100 cm\(^3\) |
| :---: | :---: |
| 2.0 | 12 |
| 4.0 | 25 |
| 6.0 | 37 |
| 8.0 | 48 |
| 10.0 | 61 |

(i) Plot a line graph on grid paper of the glucose concentration in the surrounding water after 10 minutes against the initial glucose concentration inside the tubing. [4]

(ii) Describe the relationship shown by the results in Table 2.2. [1]

(iii) Estimate the glucose concentration in the surrounding water after 10 minutes if the initial glucose concentration inside the tubing was 5.0%. Show on your graph how you obtained this value. [2]

(d) Describe how the student could test the liquid inside the Visking tubing to show that proteins were not present, including the observations for a negative result. [2]

(e) Plan an investigation to determine the effect of temperature on the rate of absorption of glucose across Visking tubing. [5]