AVERAGE ROUND (Science Quiz Bee 2023)

1. 1. Two groups of tomatoes were grown under laboratory conditions, one with humus added to the soil and one with a control without humus. The leaves of the plants grown without humus were yellowish (less green) compared with those of the plants grown in humus-enriched soil. Which of the following is the best explanation of the experimentation?

• A. The humus made the soil more loosely packed, so water penetrated more easily to the roots.

• B. The humus contained minerals such as magnesium and iron needed for the synthesis of chlorophyll.

• C. The healthy plants used the food in the decomposing leaves of the humus for energy to make chlorophyll.

• D. The heat released by the decomposing leaves of the humus caused more rapid growth and chlorophyll synthesis.

2. 2. What are homologous chromosomes?

• 1. A. The two halves of a replicated chromosome.

• B. Two identical chromosomes from one parent.

• C. Genetically identical chromosomes, one from each parent.

• D. Genetically unidentical chromosomes, one from each parent.

The diagram shows a steel bridge. One end of the bridge is fixed securely to the structure, unlike the other end which is resting on rollers as shown. Which of the following statement(s) explain(s) why one end of the bridge is resting on the rollers?

• A. II only

• B. III only

• C. I and II only

• D. I and III only

The picture shows a man pushing a box across the floor. Which of the following makes it difficult for a man to push the box?

• A. I and II

• B. I and III

• C. II and IV

• D. III and IV

John set up a circuit as shown below which consists of three bulbs, A, B, and C, as well as three different materials, X, Y, and Z. When the switch is closed only bulbs B and C light up. What are some possible reasons for this observation?

• A. I and II only

• B. II and IV only

• C. I, II and IV

• D. I, II, III, and IV

The check marks in the table below indicate the presence of the parts in three cells X, Y, and Z. Which of the following is/are animal cells?

• A. X only

• B. Y only

• C. Y and Z only

• D. X, Y, and Z

The graph below shows the number of days of each stage in the life cycle

    of an insect. Based on the graph, Johari wrote the following statements:

1. I. The larva takes 5 days to hatch from the egg.

2. II. The insect takes 40 days to become an adult.

3. III. The male insect dies soon after it fertilizes the eggs.

4. the insect takes 25 days to change from larva to pupa.

Which of the above statements(s) is/are correct?

• A. I only

• B. II only

• C. I and III only

• D. II and IV only