CSEC Biology Paper 2 May/June 2010 - Free CXC Past Paper with Answers

In an experiment on the plant species illustrated in Figure 1, the part identified as X was tested in several plants after they had grown in three different light intensities.

Figure 1. A plant species

Sets of three plants for each light intensity were tested for the following: starch, reducing sugar, protein, oil.

In the space provided below construct a table to show how the data from the experiment might be collected.

Explain why a sample of three plants was used for each test.

In the space provided below, draw a labelled diagram of the apparatus that can be used in an experiment to illustrate that Part Z will take in water for use by Part Y (in Figure 1 on page 2).

Humans also carry out other functions similar to that shown by the plant species represented at Figure 1, for example, respiration. In investigating respiration in a human being and a plant, explain how you would demonstrate that the process carried out by both organisms is the same.

Figure 2 represents the flower of the plant species shown in Figure 1.

Figure 2. Longitudinal section through the flower of the plant species

On the diagram in Figure 2, label the following parts using the symbols indicated:

P for the place where pollen is produced
O for the place that houses the ovum
S where pollen is deposited

Suggest how this flower might be pollinated. Explain your answer.

Some plant storage organs give rise to offspring. Suggest TWO advantages to the plant of having both flowers, and a storage organ that gives rise to offspring.

In an experiment on germinating seedlings, a group of Biology students made the drawings shown in Figure 3 to illustrate the changes over a five-day period.

Figure 3. Stages in a germinating seedling

Label on the drawing in Figure 3, THREE parts of the seedling shown on Day 5.

Outline the changes that took place in the seed to allow the development shown in Figure 3.

The development shown by the seedling is a type of 'movement'. What is the name given to this type of movement?

State TWO ways in which the movement shown by the seedling differs from that of an earthworm moving through its burrow.

Identify TWO physical factors that can cause an earthworm to move deeper into its burrow.

Explain why moving deeper into its burrow is important to the earthworm.

Figure 4 shows a terrestrial food web.

Figure 4. Terrestrial food web

Identify, from the food web shown in Figure 4, a food chain with FOUR trophic levels. Draw the food chain in the space provided below.

Identify, from the food web in Figure 4, ONE predator and ONE organism which is likely to be its prey.

Identify TWO characteristics that will differentiate the predator population from that of the prey.

Apart from predator/prey, identify ONE other relationship that may exist in a food web, and provide an example.

Give ONE advantage of having special relationships among organisms in a food web.

SECTION B Answer ALL questions. Write your answers in the spaces provided at the end of each question.

Identify, with the aid of diagrams, the main stages in the life history of a named insect vector of disease.

Explain how EACH stage in the life history of the insect you identified at (a)(i) might be controlled to keep the vector population in check.

Some sexually transmitted infections are caused by viruses and have been found to be without cure. Explain why viral infections are usually very difficult, if not impossible, to cure.

Apart from the nature of the AIDS virus, what OTHER factors make the control of this disease very difficult?

How is it possible for plants that have identical genetic make-up to show differences?

Suggest why it is sometimes necessary to breed plants with the same genetic make-up.

Give ONE disadvantage of breeding an identical population of organisms.

When breeding programmes are deliberately used to control the characteristics of a population of organisms, the process is called artificial selection.

Explain how this process is different from natural selection.

Genetic engineering is a modern biological technology that has been used to change the characteristics of certain organisms. How does genetic engineering differ from artificial selection?

Suggest TWO concerns people might have about using genetic engineering to alter characteristics of organisms.

With the aid of a diagram, explain how the hind limb in humans allows for movement from one place to another.

Give THREE advantages to humans of their ability to move from one place to another.

Flowering plants are usually anchored to one spot but both their gametes and seeds need to be distributed or dispersed from one place to another.

Identify TWO means by which seeds are dispersed.

Explain how any TWO characteristics of a seed may be adapted for dispersal.

CSEC Biology Paper 2 May/June 2010 Questions

Question 1 (25 marks)

Figure 1. A plant species

Figure 2. Longitudinal section through the flower of the plant species

Question 2 (15 marks)

Figure 3. Stages in a germinating seedling

Question 3 (15 marks)

Figure 4. Terrestrial food web

Question 4 (15 marks)

Question 5 (15 marks)

Question 6 (15 marks)