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PIMSO 2023 - Science - Secondary 1 - National Round

Question 1

The following image shows which level of biological organization?

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  1. Biomolecule
  2. Organelle
  3. Cell
  4. Tissue
  5. Organ

Question 2

A scientist records the average monthly temperature and precipitation of a location belonging to a certain biome. What type of plants would the scientist have observed growing in this location?

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Question 3

Which animal phylum consists of members that may display asymmetrical body?
  1. Echinodermata
  2. Cnidaria
  3. Chordata
  4. Porifera
  5. Arthropoda

Question 4

Which biomolecule is the building block of the cell wall in fungi?
  1. Cellulose
  2. Chitin
  3. Lignin
  4. Pectin
  5. Peptidoglycan

Question 5

The image below shows an onion root tip viewed under the microscope, with the chromosomes stained in red. Which cell is undergoing metaphase?

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  1. A
  2. B
  3. C
  4. D
  5. E

Question 6

Which of the following respiratory diseases that are caused by microorganisms should be treated with antibiotics?
  1. Common cold
  2. Influenza
  3. Severe acute respiratory syndrome
  4. Middle East respiratory syndrome
  5. Tuberculosis

Question 7

In the early 20th century, Marie and Pierre Curie were working on radioactivity of pitchblende, known by then to contain the element uranium. However, they found anomalous trace quantities of another material that were much more radioactive than uranium. After labouring for several months, exhausting all physical and chemical processes to extract and purify the material, they were able to make measurements of its physical properties. This was a sign that they discovered a new:
  1. element
  2. compound
  3. phenomenon
  4. property
  5. state of matter

Question 8

Temperature may affect the volume occupied by matter. Which phase/s of matter would increase its volume when heated?

Editorial assumption: Use ordinary thermal expansion with volume free to change; exceptions are discussed in the solution.
  1. solid
  2. liquid
  3. gas
  4. liquid and gas
  5. solid, liquid, and gas

Question 9

Distillation separates mixtures according to differences in what property of its components?
  1. boiling point
  2. density
  3. particle size
  4. volume
  5. none of the above

Question 10

Some rubbing alcohols that you use on your hand to kill bacteria contain ethanol. Ethanol is made up of carbon, oxygen, and hydrogen. In an experiment, a chemist determined that 160 g of ethanol contains 83 g of carbon and 56 g of oxygen. How much hydrogen is in the sample of ethanol?
  1. 83 g
  2. 56 g
  3. 160 g
  4. 21 g
  5. cannot be determined from the given information

Question 11

An unknown compound was determined to contain only carbon and hydrogen. 12.0 g sample of the compound was found to contain 1.60 g hydrogen. A chemical engineer in a factory received a 6.0 kg sample of the compound for analysis. From the given information, determine the mass of carbon in the sample received.

Original choices:
A. 0.80 kg
B. 0.8 kg
C. 5.20 kg
D. 5.2 kg
E. None of the above

Editorial review: explain the scientific result and whether the printed choices and wording determine one answer.

Question 12

You are helping your parents to cook sinigang, a popular Filipino dish composed of meat and vegetables in a clear sour broth: They asked you to boil some water to make soup and notify them as soon as the water starts to boil at 100 °C. You told them that it started to boil after ten minutes, but they are not yet ready preparing the meat and vegetables. So to conserve energy, they asked you to lower the heat. You lowered the heat just enough so that some bubbles still appear to rise to the top of the water, although it is not boiling vigorously anymore. What is the temperature of the water at this point?

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Editorial assumption: Assume the liquid remains at boiling equilibrium at the same atmospheric pressure.
  1. 95 °C
  2. not exactly 95 °C but still below 100 °C
  3. 100 °C
  4. around 105 °C
  5. Cannot be determined from the given information

Question 13

A ship leaves Manila bay at 6:00. Shown below is the distance travelled by the ship over time. When is the ship NOT accelerating?

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Original choices:
A. From 6:00 to 8:00
B. From 7:00 to 9:00
C. From 8:00 to 10:00
D. From 9:00 to 11:00
E. From 10:00 to 12:00

Editorial review: explain the scientific result and whether the printed choices and wording determine one answer.

Question 14

The Banaue Rice Terraces is a famous Philippine landmark. Built over a thousand years ago, the terraces allowed to grow rice even on mountains. On which part of the rice terraces would you have the highest kinetic energy?

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Original choices:
A. A
B. B
C. C

Editorial review: explain the scientific result and whether the printed choices and wording determine one answer.

Question 15

Which property of material refers to their capacity to absorb thermal energy?
  1. heat capacity
  2. thermal conductivity
  3. heat storage
  4. storage capacity
  5. none of the above

Question 16

Which of the following is NOT accelerating?

Editorial assumption: For the intended idealized comparison, assume straight steady flight and a raindrop that has not reached terminal speed.
  1. an airplane flying at its maximum speed 900 km/hr
  2. an airplane starting to lift off
  3. a drop of rain falling
  4. a jeepney stopping for passengers
  5. none of the above

Question 17

What happens to the kinetic energy of an object when its velocity doubles as the acceleration remains constant?
  1. The kinetic energy halves
  2. The kinetic energy remains constant
  3. The kinetic energy doubles
  4. The kinetic energy quadruples (4x)
  5. cannot be determined

Question 18

Which of the following colors in the visible spectrum has the lowest energy?

Editorial assumption: Compare the energies of individual photons.
  1. Violet
  2. Blue
  3. Green
  4. Yellow
  5. Red

Question 19

Which of the following greenhouse gasses is the primary contributor of modern-day global warming?
  1. Carbon monoxide
  2. Carbon dioxide
  3. Ozone
  4. Sulfur dioxide
  5. Methane

Question 20

The weather forecaster has predicted an incoming thunderstorm in your location. Which of the following cloud formations would you have observed?
  1. Cumulonimbus
  2. Stratonimbus
  3. Altocumulus
  4. Cirrus
  5. Contrail