IMSO 2024 Science International — Theory I

Question 1

Original source text (the original panel preserves all diagram labels, tables and choices):

Bekam, also known as wet cupping or cupping therapy, is a traditional healing
method that uses cups to create suction and pull skin into the cup, which can
help relieve pain and other issues. The cups are usually placed on areas of the
body that are often in pain, such as the back, neck, shoulders, or legs. The cups
can be heated with alcohol, herbs, or paper to create a vacuum that pulls the
skin and muscles in. The skin can become red as a result of doing this treatment.





Why does it leave reddish marks on the skin after undergoing cupping treatment?

A. The arteries narrow so that oxygen is not distributed properly due to suction
pressure.
B. The suction force from the cups breaks open capillaries under the skin.
C. More carbon dioxide accumulates in erythrocytes due to the suction pressure
of the cup.
D. Leukocytes cannot carry out the blood clotting process due to the pressure
from suction.

1. The arteries narrow so that oxygen is not distributed properly due to suction pressure.
2. The suction force from the cups breaks open capillaries under the skin.
3. More carbon dioxide accumulates in erythrocytes due to the suction pressure of the cup.
4. Leukocytes cannot carry out the blood clotting process due to the pressure from suction.

Question 2

Original source text (the original panel preserves all diagram labels, tables and choices):

During the Paris 2024 Olympics, a marathon runner is pushing her limits in the
final lap of the race. As she sprints to the finish line, her muscles are working at
maximum capacity and her body begins to experience oxygen deficiency. Due to
the shortage of oxygen in her active muscle cells, certain substance of energy
metabolism accumulate, causing a change in pH.

Which of the following options correctly identifies the nature of the pH change
and the major substance responsible for it?
pH Change Substance

A Decrease Carbon dioxide

B Decrease Lactic acid

C Increase Carbon dioxide

D Increase Lactic acid

Question 3

Original source text (the original panel preserves all diagram labels, tables and choices):

The gag reflex is a reflex contraction of the
muscles of the throat, which stops material from
entering the throat (except in swallowing) and
helps to prevent choking. The sensory nerve in
this reflex is the glossopharyngeal nerve, and the
motor nerve to the throat muscles is the vagus
nerve.

Which of the following statements correctly describes the role of the
glossopharyngeal nerve and the vagus nerve in the gag reflex?

A. The glossopharyngeal nerve provides motor control to the throat muscles,
while the vagus nerve detects potentially harmful material entering the throat.

B. The vagus nerve is responsible for sensory detection of potentially harmful
material, while the glossopharyngeal nerve controls the motor contraction of
the throat muscles.

C. The glossopharyngeal nerve detects potentially harmful material and initiates
the gag reflex, while the vagus nerve controls the motor contraction of the
throat muscles to prevent choking.

D. Both the glossopharyngeal nerve and the vagus nerve are involved in sensory
detection, with the glossopharyngeal nerve specifically handling detection
and the vagus nerve managing motor responses.

Question 4

Original source text (the original panel preserves all diagram labels, tables and choices):

The graph below illustrates the reduction in substrate concentration during an
enzymatic reaction over time. The half-life of a reaction refers to the duration
required for the concentration of a limiting reactant to decrease by half.





What is the best estimate of the half-life for this reaction?
A. 1 minute C. 4 minutes
B. 2.5 minutes D. 6 minutes

1. 1 minute
2. 2.5 minutes
3. 4 minutes
4. 6 minutes

Question 5

Original source text (the original panel preserves all diagram labels, tables and choices):

A group of students is studying the feeding relationships among various organisms
in a farm ecosystem. They have sketched a food web, as shown in the figure below.





Which of the following statements about the food web is/are correct?
I. There are only 2 herbivores in the food web.
II. The energy source of frogs comes only from grasshoppers.
III. The population of snakes will increase if the population of eagle
decreases
IV. If the intensity of light is reduced, the population of wheat will be
affected first.

A. I only C. I, II, and III only
B. II and III only D. II, III, and IV only

1. I only
2. II and III only
3. I, II, and III only
4. II, III, and IV only

Question 6

Original source text (the original panel preserves all diagram labels, tables and choices):

Cells rely on various organelles to maintain their structures and functions. Some
organelles, like in the diagram below are specialized for the breakdown and
recycling of cellular components, playing crucial roles in processes like autolysis
or the self-destruction of damaged cells and autophagy or the recycling of cellular
materials.





Given its role in autolysis and autophagy, this organelle is most abundant in
which of the following structures?





A B C D

1. A: illustrated white blood cell
2. B: illustrated red blood cell
3. C: illustrated egg cell
4. D: illustrated sperm cells

Question 7

Original source text (the original panel preserves all diagram labels, tables and choices):

You are conducting a laboratory experiment on a particular group of cells that
have been supplied with oxygen. After a certain period, you decide to cut off the
oxygen supply to these cells. Following this, you observe that the amount of
amino acid absorbed by the cells drops drastically.

Based on these observations, which of the following statements BEST explains
why the amount of amino acid absorbed by the cells decreased so significantly
when the oxygen was cut off?

A. Amino acids cannot be absorbed by the cells when oxygen is absent.
B. Amino acids are absorbed by the cells mainly through active transport.
C. Amino acids require oxygen for digestion of protein molecules by enzymes.
D. Amino acids are absorbed by the cells mainly by muscular contractions of
the cells.

1. Amino acids cannot be absorbed by the cells when oxygen is absent.
2. Amino acids are absorbed by the cells mainly through active transport.
3. Amino acids require oxygen for digestion of protein molecules by enzymes.
4. Amino acids are absorbed by the cells mainly by muscular contractions of the cells.

Question 8

Original source text (the original panel preserves all diagram labels, tables and choices):

A study examining the factors influencing evolutionary changes in animal size
was conducted. Researchers calculated the mean size of all mammals in a
region of North America over a period of 10 million years, using data from the
fossil record. Additionally, they determined the temperature in the region during
this time. The graphs representing these findings are shown below:





Which of the following is the MOST likely explanation for the trend observed in
the graphs?
A. Larger animals can more easily avoid predation, giving them a selective
advantage during cold periods when food is scarce.
B. Larger animals produce less CO₂ through respiration, contributing to lower
atmospheric CO₂ levels and decreased global temperatures.
C. The cold climate stimulates animals to grow larger, and they pass this
characteristic on to their offspring.
D. The decreased surface area to volume ratio of larger mammals gives them
a selective advantage during cold periods.

1. Larger animals can more easily avoid predation, giving them a selective advantage during cold periods when food is scarce.
2. Larger animals produce less CO₂ through respiration, contributing to lower atmospheric CO₂ levels and decreased global temperatures.
3. The cold climate stimulates animals to grow larger, and they pass this characteristic on to their offspring.
4. The decreased surface area to volume ratio of larger mammals gives them a selective advantage during cold periods.

Question 9

Original source text (the original panel preserves all diagram labels, tables and choices):

Leaves can vary greatly in shape, size, and structure. These differences help in
identifying the plant species to which they belong. By using a key, you can
systematically determine the correct classification based on specific
characteristics of the leaf. Use the key to identify Plant W.





Plant W

1. Fagus sylvatica
2. Ulmus minor
3. Fraxinus americana
4. Sorbus aucuparia

Question 10

Original source text (the original panel preserves all diagram labels, tables and choices):

In modern medicine, biotechnology plays a significant role in producing
treatments for various conditions, including diabetes. One of the most well-known
applications of biotechnology is the production of insulin, which is vital for
managing diabetes. What is the MOST likely method used to produce this insulin
through biotechnology?

A. Insulin is extracted from plants and purified in a lab.
B. Scientists insert the human insulin gene into bacteria, which then produce
insulin.
C. The insulin is synthesized entirely by chemical processes without using any
living organisms.
D. Insulin is collected from healthy humans and injected into patients who need
it.

1. Insulin is extracted from plants and purified in a lab.
2. Scientists insert the human insulin gene into bacteria, which then produce insulin.
3. The insulin is synthesized entirely by chemical processes without using any living organisms.
4. Insulin is collected from healthy humans and injected into patients who need it.

Question 11

Original source text (the original panel preserves all diagram labels, tables and choices):

Mangrove ecosystems are unique environments where various living organisms
(biotic factors) interact with non-living components (abiotic factors) to create a
balanced ecosystem. Which of the following combinations is MOST accurate in
a mangrove ecosystem?
Biotic Factor Abiotic factor

A. Types of crabs Burrows in the sand

B. Amount of sunlight received Warm temperature

C. Different species of mangrove Presence of fungi

D. Nutrients from the dead plant Warm temperature
matter

1. Types of crabs; Burrows in the sand
2. Amount of sunlight received; Warm temperature
3. Different species of mangrove; Presence of fungi
4. Nutrients from the dead plant matter; Warm temperature

Question 12

Original source text (the original panel preserves all diagram labels, tables and choices):

Plant transpiration is the process by which
water is lost from the leaves to the
atmosphere, primarily through stomata. The
rate of transpiration is influenced by external
factors like temperature, humidity, and wind
speed and internal factors such stomatal
density and cuticle thickness.

Which of the following adaptations will help plants retain moisture by reducing
rate of transpiration especially in hot and dry environment?
A. Increased leaf surface area
B. Sunken stomata
C. Thin cuticle on the surface of leaves
D. Absence of leaf hairs or trichomes

1. Increased leaf surface area
2. Sunken stomata
3. Thin cuticle on the surface of leaves
4. Absence of leaf hairs or trichomes

Question 13

Original source text (the original panel preserves all diagram labels, tables and choices):

Wong has set up an electric circuit using six light bulbs, as shown in the diagram
below:





Assuming each bulb has the same resistance, which of the following statements
is CORRECT?

I. The current passing through bulb U will be greater than the current passing
through bulb Q because bulb U is directly connected in parallel with the power
source.
II. If bulb S burns out, bulb T will not light up because they are connected in
series in the same branch.
III. Bulb P will glow brighter than bulb S because bulb P is directly connected to
the power source.
IV. All the bulbs in the circuit will glow with the same brightness because they
all have the same resistance and are connected to the same power source.

A. I, II and III only C. II and IV only
B. I and II only D. Only IV

1. I, II and III only
2. I and II only
3. II and IV only
4. Only IV

Question 14

Original source text (the original panel preserves all diagram labels, tables and choices):

Two smooth tracks of equal length have “bumps” of the same curvature where
ball X travels up and ball Y travels down with the same maximum change in
height.


X

Y



If the two balls start simultaneously with the same initial speed, which ball will
complete the journey first?

A. Ball X will complete the journey first.
B. Ball Y will complete the journey first.
C. Both balls will complete the journey at the same time.
D. Impossible to tell since the masses of ball X and Y are unknown.

1. Ball X will complete the journey first.
2. Ball Y will complete the journey first.
3. Both balls will complete the journey at the same time.
4. Impossible to tell since the masses of ball X and Y are unknown.

Question 15

Original source text (the original panel preserves all diagram labels, tables and choices):

There are three containers containing 1 L of water with varying temperatures. Hot
water (60 °C) of varying volume is then added to each container, but with different
volumes.





After the addition of hot water, each container has the same final temperature of
40 °C. If the containers are assumed to have no heat absorption and release, what
is the correct conclusion from this information?
A. The initial temperature of the water in container 2 is the smallest.
B. The initial temperature of the water in container 3 is the greatest.
C. The initial temperature of the water in container 2 is less than that of
container 3.
D. The initial temperature of the water in container 3 is greater than that of
container 2.

Question 16

Original source text (the original panel preserves all diagram labels, tables and choices):

Three different liquids, labelled A, B. and C, have their hydrostatic pressure
measured at several points. The measurement results are shown in the following
graph.

The following table shows the density data of each
liquid:
Density (kg/m3) Liquid

910 Cooking oil

1000 Water

1261 Glycerol


Determine the identity of liquids A, B and C
A B C

A. Cooking oil Water Glycerol

B. Cooking oil Glycerol Water

C. Glycerol Water Cooking oil

D. Glycerol Cooking oil Water

1. Cooking oil; Water; Glycerol
2. Cooking oil; Glycerol; Water
3. Glycerol; Water; Cooking oil
4. Glycerol; Cooking oil; Water

Question 17

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Refer to the figure below:





If friction and wind resistance are ignored, a bobsled run illustrates how kinetic
energy and potential energy can be interconverted, while the total mechanical
energy remains constant. What are the values for W and X?

A. W = 200,000 J; X = 200,000 J C. W = 250,000 J; X = 200,000 J
B. W = 200,000 J; X = 400,000 J D. W = 250,000 J; X = 400,000 J

1. W = 200,000 J; X = 200,000 J
2. W = 200,000 J; X = 400,000 J
3. W = 250,000 J; X = 200,000 J
4. W = 250,000 J; X = 400,000 J

Question 18

Original source text (the original panel preserves all diagram labels, tables and choices):

A “balloon racer” is a fun simple toy. It is made by taping an inflated balloon firmly
to a toy car, as shown below. After removing the plug of the balloon, air rushes
out of the balloon, producing a force.


Air
pushed out



Moving
directionX


The force caused the balloon and the toy car to move in direction X because this
force was greater than the ___________________.


A. Weight of the toy car and the balloon.
B. Weight of the toy car and the wheels.
C. Friction between the balloon and the toy car.
D. Friction between the wheels and the ground.

1. Weight of the toy car and the balloon.
2. Weight of the toy car and the wheels.
3. Friction between the balloon and the toy car.
4. Friction between the wheels and the ground.

Question 19

Original source text (the original panel preserves all diagram labels, tables and choices):

The diagram below shows a metal cylinder with a movable piston. The cylinder is
filled with gas of a fixed mass.





What will happen to the gas's volume, pressure, and temperature when heat is
applied?

Volume Pressure Temperature
A increases unchanged increases
B decreases unchanged decreases
C increases decreases increases
D decreases unchanged increases

1. increases; unchanged; increases
2. decreases; unchanged; decreases
3. increases; decreases; increases
4. decreases; unchanged; increases

Question 20

Original source text (the original panel preserves all diagram labels, tables and choices):

Alesha was able to arrange four bar magnets as shown below:





She introduced a new magnet



It was observed that the E’ side is attracted to the A side. If she intends to connect
the new magnet to the current arrangement, which of the following is a possible
re-arrangement?



A. C.





B. D.