CSEC Human and Social Biology Paper 2 January 2014 - Free CXC Past Paper with Answers

Figure 1 is a diagram of part of the human respiratory system.

Name the structures labelled A, B and C in Figure 1.

Choose the correct term from the list provided in brackets to complete the following sentence. (lifestyle, nutritional, respiratory, sexually transmitted)

Asthma is described as a ________________________________________________ disease.

Choose the correct term from the list provided in brackets to complete the following sentence.

(lifestyle, nutritional, respiratory, sexually transmitted)

Asthma is described as a ________________________________________________ disease.

State TWO signs/symptoms of asthma.

Table 1 shows the number of persons suffering from asthma in different parts of a country.

Location	Activity	Number of Asthma Cases per 1000 Persons
City	Business	25
Countryside A	Vegetable farming	5
Countryside B	Heavy metal industries	40

On the grid provided on page 5, draw a bar graph to represent the data in Table 1 (Location and Number of Asthma Cases).

Use your knowledge of the triggers of asthma and the data provided in Table 1 to account for the number of asthma cases in different parts of the country.

Figure 2 shows the average number of asthma attacks per person during a year-long study, and the level of Sahara dust particles in the air.

Describe the trend shown in Figure 2.

The purpose of the circulatory system is to transport substances from one part of the body to another. Figure 3 shows a micrograph of blood cells.

Name the structures labelled A and B in Figure 3.

A B

State ONE function of EACH of the structures labelled A and B.

A B

When a blood vessel is cut, a clot soon forms to prevent the entry of bacteria. During the blood-clotting process, fibrinogen is converted to fibrin. Which of these proteins (fibrinogen and fibrin) is soluble and which is insoluble?

Soluble Insoluble

Figure 4 shows a transverse section through a normal artery.

Complete the drawing of the artery in Figure 5 to show the effects of nicotine on the artery. Annotate your drawing to explain how nicotine affects the artery.

After sitting on a stool in the laboratory for several hours, Robert notices that his lower limbs feel very heavy. After walking around for a while, the heavy feeling goes away. Explain the association of tissue fluid and lymph with Robert's symptoms.

Figure 6 shows a diagram of a human nephron.

Figure 6. Diagram of a nephron

Name the parts labelled A and B in Figure 6.

A B

State ONE function of EACH of the parts labelled A and B.

A B

The kidney is an excretory organ. Name ONE OTHER excretory organ, and the substance it excretes.

Organ Substance

As a result of diabetes, Tommy’s kidneys have malfunctioned and he needs renal dialysis to control the volume and composition of his blood. Figure 7 shows a simple representation of the inside of a kidney dialysis machine.

Figure 7. Simple representation of the inside of a kidney dialysis machine

Based on the diagram in Figure 7, explain why a partially permeable membrane is needed in renal dialysis.

Why is it necessary for the dialysis fluid to have approximately the same glucose concentration as Tommy’s blood?

If Tommy’s kidneys were normal, explain how his hypothalamus would control the water content of his blood when blood solute concentration is high.

Complete the following sentence:

Sewage consists of ________________________________ and ________________________________ along with household ________________________________.

State TWO ways that remote communities could reduce the volume of household refuse produced by the community.

Your neighbours throw all their household refuse on a vacant piece of land next to the playground. Explain why this improper disposal of household refuse poses a threat to the health of the community.

Name TWO diseases that may be caused by this improper disposal of household refuse.

Two methods used in large-scale sewage treatment are activated sludge and biological filter.

Which component of the treatment plant comes immediately before the activated sludge tank?

Compare the functioning of the activated sludge and biological filter tanks. Your answer should include TWO similarities and THREE differences.

Similarities

Differences

SECTION B

Answer ALL questions in this section.

Write your answers in the spaces provided at the end of each question.

Write your answer to Question 5 here.

To reduce the chances of babies becoming ill, mothers often use sterilization and disinfection.

State TWO differences between sterilization and disinfection.

Suggest how sterilization and disinfection could be used when caring for a baby. Provide TWO situations for EACH method.

Each time Shoba goes to the beach she gets an ear infection. The doctor prescribes antibiotics for five days but each time, she stops taking the medication after three days, when she is no longer in pain. Now Shoba finds that the antibiotics are not effective anymore.

What is meant by the term 'antibiotic'?

Explain why the antibiotics are not effective anymore, and suggest the measures that Shoba should take in the future so that the antibiotics would be effective.

Write your answer to Question 6 here.

The differences among individuals are due to variation.

Distinguish between continuous and discontinuous variation, and give ONE example of EACH type of variation.

Down's syndrome arises from a chromosomal mutation. How does the chromosome number of a person with Down's syndrome differ from that of a normal person?

Sex-linked inheritance occurs when the genes are on the sex chromosome. In most cases, the genes are on the X chromosome and not on the Y chromosome.

Use a Punnett square to determine the genotype of the offspring of a cross between a female carrier of red-green colour blindness and a normal male. State the phenotype of EACH offspring.

Use $X^C X$ to denote the carrier female and $X^C Y$ to denote the normal male.

Cell phone towers have caused some concern because of their close proximity to homes. Suggest the possible

type of pollution that could result from these towers

effect of the pollution on humans

action that humans can take to reduce the effect of the pollution.

CSEC Human and Social Biology Paper 2 January 2014 Questions

Question 1 (15 marks)

TABLE 1: DATA ON ASTHMA CASES

Question 2 (15 marks)

Question 3 (15 marks)

Figure 6. Diagram of a nephron

Figure 7. Simple representation of the inside of a kidney dialysis machine

Question 4 (15 marks)

Question 5 (15 marks)

Question 6 (15 marks)