PIMSO 2023 - Science - Primary 3 - National Round

Question 1

Naked mole-rats live in dark burrows and have very poor eyesight. However, they can locate and move inside the burrows with ease. How is that so?

1. They have sensitive hairs in the body to navigate inside burrows.
2. Their naked skin is highly tactile which helps navigate inside burrows.
3. Their large teeth chew on underground roots to mark territories inside burrows.
4. Their ears catch high frequency vibrations which help locate inside burrows.
5. Their eyes have night vision to navigate well inside dark burrows.

Question 2

A botanist identifies a flowering monocot plant during an expedition to a tropical rainforest in Davao, Philippines. Which of the following flowers does the botanist most likely identify?

1. Flower a in the source figure
2. Flower b in the source figure
3. Flower c in the source figure
4. Flower d in the source figure
5. Flower e in the source figure

Question 3

1. Mouth
2. Large intestine
3. Stomach
4. Small intestine
5. Pancreas

Question 4

1. Eyelid opens
2. Cornea refracts light
3. Pupil contracts
4. Ciliary muscles relax
5. Lens become rounder

Question 5

1. Skull
2. Scapula
3. Pelvis
4. Ribs
5. Vertebral column

Question 6

While preparing for breakfast, you observed microorganisms growing on the bread, therefore making it no longer safe for consumption. Which type of microorganisms were growing on the bread?

1. Algae
2. Bacteria
3. Viruses
4. Fungi
5. Protozoan

Question 7

Balloons are usually made up of rubber because rubber is elastic. It can expand when air is blown to the balloon. What phase of matter is the rubber balloon?

1. solid
2. liquid
3. gas
4. plasma
5. none of the above

Question 8

You have to be careful when you hold a piece of egg because it can easily break. This illustrates what property of egg shells?

1. egg shells are biodegradable
2. egg shells are yellow
3. egg shells are light
4. egg shells are brittle
5. egg shells are small

Question 9

What property does the following device measure?

1. hotness or coldness of matter
2. space occupied by matter
3. amount of matter
4. color
5. texture

Question 10

1. cork < liquid < stone
2. cork < stone < liquid
3. stone < liquid < cork
4. liquid < stone < cork
5. liquid < cork < stone

Question 11

1. 0.7 g/mL
2. 7 mL/g
3. 5.0 g/mL
4. 1.4 g/mL
5. 1.4 mL/g

Question 12

1. initially when it was ice
2. while melting it to water
3. when it turned to water
4. while boiling the water to ice
5. once everything turned to steam

Question 13

What kind of energy is stored inside batteries?



Original choices (retained for review):
A. chemical energy
B. mechanical energy
C. potential energy
D. sound energy
E. heat

Editorial review: explain whether the choices give one scientifically valid answer.

Question 14

A battery powered alarm clock converts this stored energy into what form of energy when the alarm comes off?

1. sound energy
2. mechanical energy
3. light
4. potential energy
5. heat

Question 15

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

1. From 7:00 to 8:00
2. From 8:00 to 9:00
3. From 9:00 to 10:00
4. From 10:00 to 11:00
5. From 11:00 to 12:00

Question 16

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 potential energy?

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

Question 17

1. gravitational force of the earth
2. gravitational force of the sun
3. friction force on the ground
4. normal force
5. no force is necessary to keep myself on the ground

Question 18

1. solids
2. liquids
3. gasses
4. all of the above
5. none of the above

Question 19

1. Spring
2. Summer
3. Fall
4. Winter
5. None of the above

Question 20

1. East
2. West
3. North
4. South
5. None of the above