PIMSO 2022 - Science - Grade 5 - National Round

Question 1

Mimosa pudica is a plant known for seismonastic movement by folding of the leaflets upon mechanical stimulation. How do the leaflets fold upon stimulation?

1. Changes in the water pressure in the leaflet
2. Changes in the electrical signal in the leaflet
3. Changes in the glucose level in the leaflet
4. Changes in the chlorophyll pigment in the leaflet
5. e Changes in the gravity in the leaflet

Question 2

The Large Asian Leaf-nosed Bat (Hipposideros lekaguli) is found along the caves of Southeast Asia and is characterized not only by its large ears but also by its large leaf-like nose. While the ears function for echolocation to maneuver in the dark cave environment, what could be the function of the leaf-like nose?

1. Distinguish colonial territories by pheromones
2. Determine changes in air temperature
3. Adjust echolocation dynamics
4. Detect slight vibrations in the air
5. Smell insects from a long distance

Question 3

The following image shows which level of biological organization?

1. Cell
2. TIssue
3. Organ
4. Organ system
5. Organism

Question 4

1. Aorta
2. Pulmonary artery
3. Carotid artery
4. Renal artery
5. Arteriole

Question 5

1. Urethra → Ejaculatory duct → Epididymis → Seminiferous tubules → Vas deferens
2. Vas deferens → Epididymis → Seminiferous tubules → Ejaculatory duct → Urethra
3. Vas deferens → Seminiferous tubules → Epididymis → Ejaculatory duct → Urethra
4. Epididymis → Seminiferous tubule → Vas deferens → Ejaculatory duct → Urethra
5. Seminiferous tubule → Epididymis → Vas deferens → Ejaculatory duct → Urethra

Question 6

The Omicron variant is observed to be a less morbid variant of the SARS-CoV-2 virus, the causative agent of the COVID-19 disease. Researchers have found that the decreased morbidity was due to differences in the preferred infection sites, in comparison to the previous variants. Which part/s of the respiratory system would the Omicron variant infect more?

Editorial note: This is a historical 2022 question; explain the evidence and any limitation of the labeled choices.
A. a only
B. d only
C. e only
D. b and c
E. d and e
Explain the scientific reasoning and limitations of the choices.

Question 7

1. 2.08 g
2. 1.00 g
3. 3.08 g
4. Between 2.08 g and 3.08 g
5. Cannot be determined from the given information

Question 8

1. A: Drop of honey
2. B: pea
3. C: Key chain
4. D: Credit card
5. E: Plastic bag

Question 9

1. Filtration
2. Decantation
3. Chromatography
4. Dilution
5. Distillation

Question 10

1. solid
2. liquid
3. gas
4. plasma
5. all have the same forces

Question 11

Rice is a staple not only in the Philippines but in most south-east Asian countries as well. It is typically washed well before cooking. Rice is typically added with the same volume of water. Once the water starts to boil at 100 C, it is advised to lower the heat, while maintaining the boiling, until the rice cooks. What happens to the temperature while the water is boiling?

1. increases
2. stays constant
3. decreases
4. fluctuates between 90 and 100 C
5. Cannot be determined

Question 12

1. Heating the sugar slightly
2. Adding the sugar while the coffee is still hot
3. Using big cubes of sugar
4. Stirring the coffee after adding the sugar
5. None of the above

Question 13

A container ship left Manila Bay at 5:00 am. The following graph shows the distance it traveled over time. When is the acceleration of the ship HIGHEST?

Editorial note: The graph’s vertical axis is labeled speed (km/h); use that printed axis.

1. From 5:00 am to 7:00 am
2. From 7:00 am to 10:00 am
3. From 10:00 am to 1:00 pm
4. From 1:00 pm to 3:00 pm
5. None of the above

Question 14

Water feels refreshing especially on hot summer days. Going to the beach, swimming pools, or water parks is a fun way to “beat the heat”. This illustrates what property of water?

1. Low thermal conductivity
2. High thermal conductivity
3. Low heat capacity
4. High heat capacity
5. None of the above

Question 15

1. red
2. yellow
3. green
4. indigo
5. blue

Question 16

1. 60 km/hr
2. 90 km/hr
3. 36 km/hr
4. 50 km/hr
5. None of the above

Question 17

1. position
2. mass
3. speed
4. mass and speed
5. position, mass, and speed

Question 18

Please refer to the graph shown on Question number 13: At which time interval is the ship covering the largest distance?

Editorial note: The graph’s vertical axis is labeled speed (km/h); use that printed axis.

1. From 5:00 am to 7:00 am
2. From 7:00 am to 9:00 am
3. From 12:00 nn to 1:00 pm
4. From 1:00 pm to 3:00 pm
5. From 2:00 pm to 3:00 pm

Question 19

1. Malfic
2. Intermediate
3. Rhyolitic
4. Dacitic
5. Ultramafic

Question 20