CSEC Biology Paper 2 January 2018 - Free CXC Past Paper with Answers

Complete Table 2 by listing the final digestive products of the three macronutrients.

TABLE 2: MACRONUTRIENTS AND FINAL PRODUCTS OF DIGESTION

Outline how the final products of the digestion of protein and fat are transported from the gut to the liver.

Protein Fat

The line diagram below summarizes the role of the pancreatic hormones in the control of blood glucose levels. Complete the diagram by filling in the boxes with the names of Hormones X and Y.

              ┌─────────────────┐
              │   Hormone X     │
              └─────────────────┘
                     ↑ ↓
Glucose <───────────> Glycogen
                     ↑ ↓
              ┌─────────────────┐
              │   Hormone Y     │
              └─────────────────┘

Explain the role of the liver in the homeostatic control of blood glucose levels.

Figure 1 shows the variation in blood glucose concentration for two persons, A and B, during the course of 48 hours. Use the information in Figure 1 to answer the questions that follow.

Which person is MOST likely suffering from diabetes mellitus? Give ONE reason for your answer.

Based on the data in Figure 1, suggest the range for blood glucose concentration in a healthy person.

Figure 2 is a diagram of an enlarged section of the human lung.

Name the structures labelled I, II, III and IV in Figure 2. I II III IV

State the function of EACH of the parts labelled II and IV in Figure 2. II IV

Cigarette smoking is a public health concern because cigarette smoke contains chemicals that can destroy lung tissue.

State TWO ways in which the appearance of the lung of a smoker differs from that of a non-smoker.

Suggest TWO benefits of placing a ban on the smoking of cigarettes in public places.

Name the addictive component in cigarettes and suggest ONE negative impact of drug addiction. Addictive component Negative impact

The alveolus has a function similar to that of a dicotyledonous leaf. State THREE ways by which a dicotyledonous leaf is adapted to carry out this function.

With the aid of a diagram of a reflex arc, describe the response of an individual whose skin suddenly comes into contact with a hot surface.

Diagram of a reflex arc

Description

The skin plays a role in maintaining a constant body temperature. Explain the skin's role in the reduction of internal body temperature, and suggest ONE reason why the internal body temperature should be kept constant. Role: Reason:

Scientists predict that global temperatures will continue to rise over the next decade. State TWO factors that have contributed to rising global temperatures, and state TWO negative effect of rising global temperatures on biological diversity in the Caribbean.

Name THREE types of diseases and state ONE example of EACH type of disease.

Immunity may be naturally or artificially acquired.

Discuss THREE differences between natural immunity and artificial immunity, and describe any THREE steps of the mechanism (in the body) by which artificial immunity is acquired.

Meiosis results in the formation of gametes. List TWO important events that occur during meiosis that can lead to genetic variation among offspring.

Describe the process by which the male gamete reaches the female gamete in a flower.

Both parents of a haemophiliac child have the normal blood clotting trait. Use a genetic diagram to explain how this child could inherit the trait for haemophilia.