CIE iGCSE Co-Ordinated Science B13.1 Coordination and response Exam Style Questions Paper 1
Question
A plant in a pot is placed on its side in a dark cupboard. The shoots grow upwards.
What is this an example of?
A decomposition
B gravitropism
C photosynthesis
D phototropism
▶️Answer/Explanation
Ans : B
Question
When a seed germinates in the soil, the root grows downwards.
Which type of response is the root exhibiting?
(A) negative gravitropism
(B) negative phototropism
(C) positive gravitropism
(D) positive phototropism
▶️Answer/Explanation
Ans : C
Question
The graph shows the pulse rate over a period of time.
At which point is adrenaline released into the blood?
▶️Answer/Explanation
Ans : A
Question
The graphs show the pupil diameter and heart rate of a person over a period of 30 minutes. The person was given an unexpected shock at one point during the 30 minutes.
At which time did the person experience a shock causing them to release adrenaline?
(A) 5 minutes
(B) 10 minutes
(C) 15 minutes
(D) 25 minutes
▶️Answer/Explanation
Ans: D
Question
The diagram shows three different neurones which form the reflex arc.
Which row correctly identifies X, Y and Z?
▶Answer/Explanation
Ans : B
Question
In which order does an impulse pass along neurones during a reflex action?
(A) motor → relay → sensory
(B) motor → sensory → relay
(C) sensory →motor → relay
(D) sensory → relay → motor
▶️Answer/Explanation
Ans: D
Question
The diagram shows structures in a section through the front of the eye.
When reading a book, how are the labelled structures involved in focusing the eye?
| 1 | 2 | 3 | |
|---|---|---|---|
| A | contracts | thicker | slackens |
| B | contracts | thinner | tightens |
| C | relaxes | thicker | tightens |
| D | relaxes | thinner | slackens |
▶️Answer/Explanation
Answer: A
Explanation: When reading a book, the ciliary muscles (structure 1) contract, causing the suspensory ligaments (structure 3) to slacken. This allows the lens (structure 2) to become thicker and more convex, increasing its refractive power to focus on nearby objects.
Question
A plant shoot grows towards a light source. This is an example of what?
A. gravitropism
B. homeostasis
C. transpiration
D. phototropism
▶️Answer/Explanation
Answer: D. phototropism
Explanation: Phototropism is the growth of a plant in response to light. In this case, the plant shoot grows towards the light source, which is an example of positive phototropism.
Question
A person touches a hot object with their hand. They quickly pull their hand away. Which statement is correct?
A. The effector is their hand.
B. The effector is the hot object.
C. The receptor is in the muscles of their arm.
D. The receptor is in the skin of their hand.
▶️Answer/Explanation
Answer: D. The receptor is in the skin of their hand.
Explanation: The receptor that detects the heat is located in the skin. When the receptor is stimulated, it sends a signal to the nervous system, which then triggers a reflex action to pull the hand away.
Question
A growing seedling was held in position as shown in the diagram.
It was then placed in the dark for 3 days. Which diagram shows the shape of the root and the shoot of the same seedling after the 3 days?
▶️Answer/Explanation
Answer: D
Explanation: In the absence of light, the shoot will grow taller and thinner (etiolation), while the root will continue to grow downward due to gravitropism.
Question
Which diagram shows the sequence of neurones in a reflex arc, and the direction of travel of the electrical signal?
▶️Answer/Explanation
Answer: A
Explanation: The reflex arc involves sensory neurones, relay neurones, and motor neurones, with the signal traveling in a specific direction.
Question
In a reflex arc, which structure carries nerve impulses towards the central nervous system?
A. effector
B. motor neurone
C. sensory neurone
D. spinal cord
▶️Answer/Explanation
Answer: C
Explanation: The sensory neurone carries nerve impulses from the receptor to the central nervous system (CNS). This is the first step in the reflex arc, which allows for a rapid response to stimuli.