CSEC Integrated Science Paper 2 May/June 2013 - Free CXC Past Paper with Answers

Describe how Ricki's chest (intercostal) muscles and ribcage operate to cause inhalation and exhalation of air.

Suggest how his breathing rate changes as he runs up the hill.

Give a reason for your answer in (a) (ii).

Explain how the movement of Ricki's diaphragm allows him to breathe in, when he sings or engages in strenuous activity.

State TWO differences between the air that Ricki inhales and the air that he exhales.

What is the term used to describe this type of respiration?

Write a word equation for the process of respiration that involves oxygen.

Name ONE nutrient Ricki can use to provide sufficient energy for his exercise.

Table 1 is the data of a survey which compares the median age at which 1000 tobacco smokers and 1000 non-smokers died.

TABLE 1: MEDIAN AGE AT DEATH OF TOBACCO SMOKERS AND NON-SMOKERS

Category	Median Age (years)
	40
Non-smokers	0
Tobacco Smokers	50

Figure 1 on page 5 shows the data for non-smokers. On the same grid, using the scales provided, plot a graph to represent the data for the tobacco smokers.

Label the axes on the graph.

State an appropriate title for the graph.

According to the trends presented in the graphs, at what age did the SAME number of smokers and non-smokers die?

From the graph, at what age will 250 non-smokers die?

Based on the trends in the graphs, what can be concluded about the effect of smoking tobacco on life expectancy?

State ONE likely difference between the lungs of the smokers and the lungs of the non-smokers.

Distinguish between corrosion and rusting.

Corrosion Rusting

In an experiment to determine the conditions necessary for rusting, a student prepares three boiling tubes as shown in Figure 2.

Figure 2. Boiling tubes

Boiling Tube A contains an iron nail, is sealed with a stopper and has anhydrous calcium chloride.
Boiling Tube B contains an iron nail exposed to air.
Boiling Tube C contains an iron nail placed in boiled water and is sealed with paraffin.

After one month, the student observes the iron nails in the boiling tubes.

In which boiling tube will the nail show the MOST rust?

Explain your answer in (b) (i) on page 6.

What is the purpose of the anhydrous calcium chloride in Boiling Tube A?

Which boiling tube is set up as a control?

If stainless steel nails are used in the experiment instead of iron nails, would rusting take place? Give a reason for your answer.

Based on your answer in (b) (v) above, suggest ONE use of stainless steel in the home.

State ONE method that can be used to prevent rusting.

John noticed that his father replaces his garden taps made from brass with plastic taps. Outline TWO advantages and TWO disadvantages of using the plastic taps.

Advantages

Disadvantages

Figure 3 shows the reproductive system of a human female.

Figure 3. Diagram of human (female) reproductive system

Label the parts X, Y and Z on Figure 3.

State TWO structures that are present in the reproductive system of human males but are not present in that of females.

Figure 4 shows the branch of a flowering plant.

Figure 4. Branch of a flowering plant

Explain how this plant may be reproduced by: Asexual reproduction

Sexual reproduction

Asexual reproduction

Overpopulation is a problem encountered in some developing countries. Suggest TWO ways by which government or individuals can overcome this problem.

Figure 5 shows the growth curve for Seedlings A and B.

Figure 5. Growth curve for Seedlings A and B

Which seedling, A or B has the HIGHEST growth rate?

What is the maximum height reached by Seedling A?

What is the maximum height reached by Seedling B?

Give TWO possible reasons for the difference in the maximum height reached by Seedlings A and B.

Distinguish among conduction, convection and radiation of heat energy. Conduction Convection Radiation

Distinguish among conduction, convection and radiation of heat energy.

Give ONE example of a conductor and ONE example of an insulator. Conductor Insulator

Figure 6 shows a pot of water being heated on a flame.

Figure 6. Diagram showing a pot of water being heated

By which method is heat energy transferred from the

By which method is heat energy transferred from the outside of the pot to the inside of the pot?

bottom of the water to the top of the water?

Figure 7 shows the diagram of an experiment which a student carried out. Five rods made from different materials are used. Low melting point wax is used to attach a thumbtack to one end of each of the rods. The rods are then placed in the beaker of boiling water. As the temperature of the wax reaches its melting point the thumbtacks fall off the rod. The order in which the thumbtacks fall off is C, followed by A, followed by D, followed by B, and followed by E.

Figure 7. Metal rods in a beaker of boiling water

Suggest an aim for this experiment.

Which rod is the BEST conductor?

Which rod is the BEST insulator?

List TWO variables that must be held constant in this experiment.

Why is the water constantly heated throughout the experiment instead of placing the rods in a beaker of boiling water without using a flame?

Figure 8A shows a warehouse before renovation of its roof and Figure 8B shows the warehouse after renovation of its roof.

Figure 8A

Before renovation of the roof

Figure 8B

After renovation of the roof

Workers find that the warehouse shown in Figure 8B is much cooler than the warehouse shown in Figure 8A. Give a scientific explanation for this observation.

State THREE differences between the transport of nutrients in plants and the transport of nutrients in humans.

Chandra is a cyclist who often rides on a rocky terrain and across a narrow bridge to her home daily. Explain how Chandra's circulatory and respiratory systems function in enabling her to make her daily rides.

Describe the functioning of the nervous system in enabling Chandra to perform her daily rides.

Identify TWO materials that can be used for making a bicycle frame and state the property of EACH material that makes it suitable for making the frame.

Write your answer to Question 5 here.

Anna notices a rainbow in the sky.

Write your answer to Question 6 here.

Name the THREE primary colours of light in the rainbow.

Describe how Anna could create secondary colours with spotlights on a white wall.

Mr James builds a shed in his backyard and uses an electrical extension cord to power the 60W light bulb in the shed. (i) If the voltage in his house is 120V, calculate the current in the extension cord when the bulb is turned on. (ii) The James family moves the washing machine rated at 360W, 120V and 3A to the shed and plugs it into the same extension cord used in (c) (i) above. Explain the safety of this action by identifying TWO possible hazards from the electrical circuits. (iii) The circuit is overloaded when a blow dryer and a clothes iron are plugged in on the same socket with the extension cord. What device in the house prevents the house wiring from burning? Describe how it works.

If the voltage in his house is 120V, calculate the current in the extension cord when the bulb is turned on.

The James family moves the washing machine rated at 360W, 120V and 3A to the shed and plugs it into the same extension cord used in (c) (i) above. Explain the safety of this action by identifying TWO possible hazards from the electrical circuits.

The circuit is overloaded when a blow dryer and a clothes iron are plugged in on the same socket with the extension cord. What device in the house prevents the house wiring from burning? Describe how it works.

CSEC Integrated Science Paper 2 May/June 2013 Questions

Question 1 (25 marks)

TABLE 1: MEDIAN AGE AT DEATH OF TOBACCO SMOKERS AND NON-SMOKERS

Question 2 (15 marks)

Figure 2. Boiling tubes

Question 3 (15 marks)