Biology Matters for GCE 'O' Level

Questions and Answers

What organ serves as the information centre in the human body?

Heart

Liver

Lungs

Brain (correct)

Which component is NOT part of the nervous system?

Nerves

Spinal cord

Brain

Kidneys (correct)

What is the role of sensory neurons in the nervous system?

Connect the brain to other parts of the body

Transmit signals to muscles

Carry impulses from sense organs to the brain or spinal cord (correct)

Interpret received information

What is the term for the effectors in a reflex arc?

Muscles or glands Signup and view all the answers

How do relay neurons contribute to reflex actions?

They connect sensory neurons to motor neurons Signup and view all the answers

What is the main function of the nervous system?

To co-ordinate and regulate bodily functions Signup and view all the answers

Which of the following is primarily responsible for responding to a specific stimulus?

Effectors Signup and view all the answers

In a reflex action, what do sensory receptors primarily do?

Detect stimuli from the environment Signup and view all the answers

What occurs to the pupil when light intensity increases?

The pupil constricts Signup and view all the answers

Which of the following actions happens to the pupil in low light conditions?

The pupil dilates Signup and view all the answers

What physiological process causes the pupil to change size?

Affecting the iris muscles Signup and view all the answers

What could cause the pupils to dilate apart from changes in light intensity?

Emotional reactions Signup and view all the answers

During a fight-or-flight response, what happens to the pupils?

They dilate Signup and view all the answers

What is the main role of pupil dilation in low light situations?

To increase light intake Signup and view all the answers

Which of the following best describes the mechanism of pupil constriction when bright light is present?

Reflexive action of the iris Signup and view all the answers

Why would someone experience pupil dilation when in a state of danger?

To maximize visual perception Signup and view all the answers

Which of the following structures are part of the central nervous system?

Spinal cord Signup and view all the answers

What is the primary function of nerves in the nervous system?

To transmit nerve impulses Signup and view all the answers

How are neurons related to nerves?

Nerves are made up of neurons Signup and view all the answers

What is a synapse in the context of the nervous system?

A junction where nerve impulses can converge or diverge Signup and view all the answers

What is presbyopia primarily characterized by?

Difficulty in focusing on near objects Signup and view all the answers

Which factor is a possible cause of presbyopia?

Decrease in lens elasticity Signup and view all the answers

What is the significance of reflex arcs in the nervous system?

They enable rapid responses to stimuli Signup and view all the answers

In a scenario where multiple stimuli are received, what allows the nervous system to respond to different effectors simultaneously?

Multiple synapses in neurons Signup and view all the answers

How does decreased lens elasticity affect vision?

It results in blurred vision for near objects Signup and view all the answers

What role does age play in presbyopia?

Age-related changes contribute to lens elasticity loss Signup and view all the answers

What type of action is primarily mediated by nerve impulses traveling from the brain to effectors?

Voluntary actions Signup and view all the answers

Which process describes the pathway of nerve impulses that leads to the body’s response to stimuli?

Reflex arc Signup and view all the answers

Which is NOT a typical measure used to correct presbyopia?

Color filters for better contrast Signup and view all the answers

What might a common symptom of presbyopia be?

Difficulty reading small print Signup and view all the answers

What is a common misconception about presbyopia?

It can be cured with eye exercises Signup and view all the answers

How can presbyopia be effectively managed?

Using corrective lenses designed for close-up work Signup and view all the answers

What is the primary process of adjusting the lens of the eye to form clear images called?

Focusing Signup and view all the answers

What must occur for light rays to form a clear image on the retina?

They must converge. Signup and view all the answers

How does the shape of the lens change when focusing on a distant object?

It becomes flatter. Signup and view all the answers

What is indicated by the near point of the eye?

The minimum distance to see clearly. Signup and view all the answers

What effect does moving an object closer to the eyes have on the lens?

The lens adjusts and becomes more curved. Signup and view all the answers

What is the purpose of focusing in the human eye?

To form clear images at varying distances. Signup and view all the answers

Which of the following statements about the lens is accurate?

The lens alters its shape to focus light. Signup and view all the answers

What happens to the near point as a person ages?

It increases in distance from the eye. Signup and view all the answers

Study Notes

Nervous System Overview

Central nervous system consists of the brain, spinal cord, and nerves, regulating bodily functions and responses to stimuli.
Communication pathways involve receptors, sensory neurones, relay neurones, motor neurones, and effectors to coordinate reflex actions.

Eye Structure and Function

The human eye is structured to facilitate vision by focusing light onto the retina.
Focusing, or accommodation, adjusts the lens shape for clear images of objects at varying distances.

Reflex Actions

Reflex actions involve a quick response to specific stimuli through a pathway known as the reflex arc.
Sensory information is transmitted to the brain to trigger a response, which is then sent to effectors (muscles or glands).

Presbyopia

Presbyopia is a condition characterized by the loss of lens elasticity, impacting the ability to focus on nearby objects, leading to blurry vision.
Commonly occurs with age as the lens becomes less flexible.

Pupil Response

The pupil can constrict and dilate in response to changes in light intensity.
Pupils also dilate due to emotional reactions, such as fear or excitement, driven by hormonal changes.

Measures for Vision Correction

Various corrective measures exist for vision impairments, including glasses, contact lenses, and surgical options; each work by adjusting light entry for clearer images on the retina.

Near Point of Focus

The near point is the closest distance at which an object can be seen clearly. This is important in assessing vision and determining necessary corrective measures.

Additional Concepts

Synapses serve as junctions for nerve impulses, allowing simultaneous transmission to multiple effectors.
Understanding the interaction between the central nervous system and sensory experiences is critical for grasping how organisms react to their environment.

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Description

Explore Chapter 10 of 'Biology Matters for GCE 'O' Level' focusing on the Nervous System and the Eye. This quiz will challenge your understanding of key concepts related to these essential topics in biology. Test your knowledge and deepen your appreciation for the human body's information processing systems.

Biology Matters for GCE 'O' Level - Chapter 10