Co-ordination & Response in Biology

These flashcards cover key terms and concepts related to the coordination and response functions of the human nervous system as introduced in the lecture notes.

Central Nervous System (CNS)

Comprises the brain and spinal cord, serves as the main control center for processing information.

Peripheral Nervous System (PNS)

Includes all the nerves outside the CNS; connects the brain and spinal cord to the rest of the body.

Neurone

A nerve cell that transmits electrical impulses; consists of a cell body, axon, and dendrites.

Synapse

The junction between two neurones where signal transmission occurs, involving a synaptic cleft.

Neurotransmitter

A chemical messenger released at a synapse that transmits signals from one neurone to another.

Myelin Sheath

An insulating layer that surrounds axons, allowing faster transmission of electrical impulses.

Reflex Arc

The neural pathway that mediates a reflex action, including sensory, relay, and motor neurones.

Rod Cells

Photoreceptor cells in the retina that are sensitive to light and function well in low-light conditions.

Cone Cells

Photoreceptor cells in the retina that detect color and are responsible for sharp central vision.

Accommodation

The process by which the lens changes shape to focus on objects at varying distances.

Myopia

Short-sightedness; a condition where distant objects appear blurry due to over-curvature of the lens.

Hyperopia

Long-sightedness; a condition where close objects appear blurry due to under-curvature of the lens.

Cataracts

A condition involving cloudiness of the lens, leading to blurred vision and potentially blindness.

Pupil Reflex

An involuntary response to changes in light intensity, involving dilation and constriction of the pupil.

Dendrites

Extensions of a neurone that receive signals from other neurones, facilitating communication.

Axon

The long, slender projection of a neurone that conducts electrical impulses away from the cell body.

Relay Neurone

Neurones found within the CNS that connect sensory and motor neurones.

Sensory Neurone

A neurone that carries electrical impulses from sensory receptors towards the Central Nervous System (CNS).

Motor Neurone

A neurone that transmits electrical impulses away from the CNS to effectors (muscles or glands) to bring about a response.

Somatic Nervous System

A division of the PNS responsible for voluntary control of body movements via skeletal muscles.

Autonomic Nervous System

A division of the PNS that regulates involuntary functions, such as heart rate, digestion, and respiration.