PL AR RSO P3L22 Plant Systems II WS_1

Primary 3

Rocket Science OEQ

Name ______________
Tutor
Topic PLANT SYSTEMS II (LESSON 22)

______________

PLANT SYSTEMS II (LESSON 22)

Primary 3: Rocket Science OEQ

Lesson Outline

• Notes
• Activity 1: Open-ended Questions
• Activity 2: Science in Daily life

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Primary 3: Rocket Science OEQ

Summary of plant parts and their respective functions

Plant part Functions
Stem - Transports food, water and mineral salts
Leaf - Contains chlorophyll which traps light
energy to enable the plant to undergo
Root photosynthesis

Flower -Contains small openings known as stomata

Fruit to allow gaseous exchange between the plant
Seed
and its surrounding
- Absorbs water and mineral salts from the
soil
- Anchors the plant firmly to the ground
- Enables the plant to bear fruits and seeds to

allow reproductionto take place
- Acts as a platform for fertilisation to occur
- Contains and protects the seeds

- Enables the plant to reproduce
-Enables another life cycle of plant to take
place (Germination)

• For photosynthesis to occur, carbon dioxide and water is needed.
• Chlorophyll traps light energy from the sun to enable photosynthesis

to occur.

• The light energy is converted to chemical potential energy in the
form of sugars (such as glucose) and oxygen is produced.

• The photosynthesis equation:

• When in excess, these sugars will be converted to
which is stored in leaves and sometimes in storage roots (e.g.
carrots) or underground stems (e.g. potato).

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During the day when the sun is shining, the stomata of leaves are kept open
to allow gaseous exchange so that photosynthesis can occur. You can watch
the process of stomata closing instead in this video.

stomata

AR Model –
Stomata

https://www.youtube.com/watch?v=AwyrqfNTuxQ
While the stomata are open, water loss occurs from the leaves in a process
called transpiration. In fact, transpiration of water from plants back into the
air is actually a part of the water cycle.

The water loss from leaves due to transpiration is what drives the movement
of water through the xylem through wicking action, as shown in the following
video.

https://www.youtube.com/watch?v=mc9gUm1mMzc&t=21s

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Primary 3: Rocket Science OEQ

Activity 1 – Open-ended Questions
1. The diagram belowshows the movement of substances in a plant .

leaves stem roots
Movement of substances in a plant

(a) Name the substance and explain why the substance is important in the

growth of a plant. [1]

SSeet-uupp11 Set-up 2

The following procedure was recorded in the experiment.

TIME STEPS DESCRIPTIONS
Add 10ml of water to set-up 1 and
9 a.m. 1 add 30ml of water to set-up 2.

6 p.m. 2 Record the height of both plants.
- 3 Repeat steps 1 & 2 over 3 days.

(b) What is the aim of the experiment? [1]

(c) The student decided to prepare a control set-up for the experiment. [1]
What would be in the control set-up?

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2. The flowchart below describes the functions of different parts of a
flowering plant.

Plants Parts

Does it help to Yes

support the plant? A

No

Does it help the plant Yes B
to take in water?

No

Does it help the plant Yes C
to make food?

No

D

(a) Identify partsA, B, C and D of the flowering plant based on the diagram

above. [2]

A:

B:

C:

D:

(b) What would happen to the plant if part B is removed? Give a reason [1]

for your answer.

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3. Four identical adult plants,A, B, C and D, are placed in the school garden.
They are grown under different conditions as shown in the table below. A
tick ( ) indicates the conditionthat is present for each of the plant

Plants Conditions
A Air Water
B
C

D

(a) Which plant (A, B, C or D) will most likely survive after 1 week? [1]

(b) Explain your answer in (a). [1]

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The diagram below shows a flowering plant. Points P,Q, R and S show
possible places to cut the plant.

QP
R

S

plant

(c) At which point must the plant be cut so that it will not be able to take in

water and minerals at all? [1]

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Primary 3: Rocket Science OEQ

4. Lily had two similar plants, S and T. She removed the roots of plant S and
planted both plants in her garden.

wind wind

plant S plant T

(a) State which plant is more likely to be blown away by the wind. [2]
Explain your answer clearly.

(b) The diagram below shows plant T. [1]
Name part X and state its function.

X

plant T

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Primary 3: Rocket Science OEQ

Activity 2: Science in Daily Life: How do trees transport water from roots to
leaves?

https://www.youtube.com/watch?v=9-dicqNoODg
Discussion Questions:
1) What part of the root does water first enter the plant?
2) Why are these structures long and elongated and are in
numerous numbers?
3) What is the name of the opening where water escapes from the
leaf? (1.10)

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