Nervous system and eye

Multiple Choice

Why are reflex actions important for survival?

• They allow us to think before acting.

• They help us respond quickly to danger.

• They slow down our reactions to stimuli.

• They only occur when we are asleep.

Open Ended

Describe the pathway of a nerve impulse in a reflex arc, starting from the receptor and ending at the effector.

Fill in the Blanks

The

is the tough white outer covering of the eyeball that protects it from mechanical damage.

Multiple Choice

Which part of the eye controls the size of the pupil to regulate the amount of light entering the eye?

• Iris

• Sclera

• Conjunctiva

• Retina

Multiple Choice

Which of the following is NOT a function of the tear gland?

• Lubricate conjunctiva

• Produce mucus

• Wash away dust particles

• Keep cornea moist

Open Ended

Explain how the external features of the eye help protect it from damage.

Multiple Select

Select all the parts of the eye that are involved in focusing.

• Lens

• Retina

• Cornea

• Aqueous chamber

Open Ended

Based on what you know about the functions of the various parts of the eye, what are some possible causes of blindness?

Multiple Choice

Which part of the eye is responsible for changing the thickness of the lens to focus light onto the retina?

• Ciliary body

• Cornea

• Vitreous chamber

• Optic nerve

Multiple Select

Select all the parts of the eye that help to keep the eyeball firm and refract light.

• Aqueous chamber

• Vitreous chamber

• Choroid

• Lens

Open Ended

Explain how the structure and function of the fovea contribute to detailed colour vision in bright light.

Multiple Choice

Which part of the eye transmits nerve impulses produced by photoreceptors to the brain?

• Optic nerve

• Blind spot

• Rectus muscle

• Lens

Fill in the Blanks

The retina contains photoreceptors called

and rods.

Multiple Choice

Which part of the eye is responsible for controlling the amount of light entering the eye?

• Lens

• Retina

• Iris

• Cornea

Open Ended

Q: Identify the stimulus and effector.

Multiple Choice

Arrange the steps of the pupil reflex arc in the correct order.

• Photoreceptors produce nerve impulses, stimulus occurs, nerve impulses transmitted to relay neurones, nerve impulses transmitted to motor neurones, nerve impulses transmitted to muscles of iris

• Stimulus occurs, photoreceptors produce nerve impulses, nerve impulses transmitted to relay neurones, nerve impulses transmitted to motor neurones, nerve impulses transmitted to muscles of iris

• Nerve impulses transmitted to relay neurones, stimulus occurs, photoreceptors produce nerve impulses, nerve impulses transmitted to motor neurones, nerve impulses transmitted to muscles of iris

• Stimulus occurs, nerve impulses transmitted to relay neurones, photoreceptors produce nerve impulses, nerve impulses transmitted to motor neurones, nerve impulses transmitted to muscles of iris

Fill in the Blanks

The circular muscles and radial muscles in the iris are described as

because they work against each other.

Open Ended

Explain how the iris controls the amount of light entering the eye in both bright and dim light.

Multiple Choice

Which terms should be used to describe the actions of muscles and the pupil when there are changes in light intensity?

• Muscles contract and expand; pupil contracts and relaxes

• Muscles contract and relax; pupil constricts and dilates

• Muscles expand and relax; pupil contracts and relaxes

• Muscles constrict and dilate; pupil contracts and relaxes

Multiple Choice

Which parts of the eye are responsible for refracting light rays onto the lens?

• Cornea and aqueous humour

• Lens and retina

• Optic nerve and cornea

• Retina and aqueous humour

Open Ended

Describe the process by which the lens of the eye adjusts to focus on objects at different distances.

Multiple Select

Select all the correct statements about the process of focusing on a distant object.

• Ciliary muscles relax

• Suspensory ligaments become taut

• Lens becomes thinner and less convex

• Lens becomes thicker and more convex

Multiple Choice

When focusing on a distant object, which of the following changes occur in the eye?

• Ciliary muscles contract, lens becomes thicker

• Suspensory ligaments slacken, lens becomes more convex

• Ciliary muscles relax, lens becomes thinner and less convex

• Lens becomes thicker and more convex

Fill in the Blanks

Fill in the blank: When focusing on a near object, the ciliary muscles

and the lens becomes thicker and more convex.

Open Ended

Using your knowledge of the human eye, can you explain why cataracts results in vision that is blurred with faded colour?

Open Ended

Summarize what you have learned about reflex actions and their types. How do you think these reflexes help us in daily life?