Stimulus and Response

Flashcards about stimulus and response in humans, plants and animals.

What does the Central Nervous System include?

Brain & Spinal Cord

What does the Peripheral Nervous System consist of?

Nerve cells that connect the central nervous system with receptors & effectors.

What are the functions of the Human Nervous System?

To detect and respond to a stimulus.

What does a sensory organ have to detect a stimulus?

Receptors.

What are Nerve Impulses?

Electrical signals that flow through the nerve cells to the brain.

What are Effectors?

Part of the body that responds. E.g. Muscles and Glands.

What is a Voluntary Action?

Requires a conscious effort. E.g. Speaking, Walking.

What is an Involuntary Action?

Occurs automatically, cannot be controlled and does not require conscious effort. E.g. Heartbeat and Breathing.

What does the eye do?

Enables us to see.

What is the function of the Pinna?

Collects sound waves and sends them to the auditory canal.

What is the function of the Ear drum?

Receives the sound waves and vibrates.

What does the ear do?

Enables us to hear.

What does the roof of the nasal cavity have?

Sensory cells or smell receptors to detect smell.

What is the function of the tongue?

Gives us the sense of taste.

What does each taste bud contains?

Taste Receptors.

The more the number of receptors present, then…

The more the sensitivity of that part of the skin.

The nearer the receptors are to each other, then…

The more sensitive is the skin to stimulation.

The thinner the epidermis, then…

The more sensitive that part of the skin.

What does the skin do?

Detects touch.

What can affect the sensitivity of the sensory organs?

Unhealthy lifestyles and high risk jobs

What helps when one Cannot See Small/Tiny Objects?

Magnifying glass, Microscope

What helps when one Cannot See Far Objects?

Binocular, Telescope

What helps when one Cannot See Thru Opaque Objects

Xray machine, Ultrasound scanning device

What helps when one Cannot See At All Angles

Periscope

What is positive phototropism?

Shoot grows toward light.

What is negative phototropism?

Roots grow away from light.

What is positive geotropism?

Roots grow downwards in the direction of gravity.

What is negative geotropism?

Shoots grow in the opposite direction of gravity.

What is positive hydrotropism?

Root grows toward the water.

What is negative hydrotropism?

Shoots grow away from the water.

What is stereoscopic vision?

Both eyes located in front of the head. A narrow field of vision. Fields of vision overlap to a great extent.

What is monocular vision?

Both eyes located at the sides of the head. A wide field of vision. Fields of vision do not overlap or overlap only slightly.

How does a Porcupine use responses to stimuli to survive?

Quills respond when being attacked. That protect them against predators.

How does a Electric eel use responses to stimuli to survive?

Producing electric field to determine the direction & changes in the environment.

How does a Beetle use responses to stimuli to survive?

Secretion of pheromone helps in finding a partner.

How does a Fish use responses to stimuli to survive?

Lateral line detects water changes, traces of prey & assists movement.