Sense Organs, Nervous System, and Homeostasis Review

A comprehensive set of vocabulary flashcards covering sense organs, receptor types, the divisions of the nervous system, neuron anatomy, reflex arcs, homeostasis, and the endocrine system based on the provided lecture notes.

Stimulus

A change in the environment.

Receptor

Detects a stimulus and sends a message.

Effector

A muscle or gland that carries out a response.

Thermoreceptors

Receptors located in the skin and hypothalamus that detect temperature.

Mechanoreceptors

Receptors located in the skin, muscles, and ears that detect touch, pressure, sound, and movement.

Chemoreceptors

Receptors located in the nose and taste buds that detect chemicals.

Photoreceptors

Receptors located in the eyes that detect light.

Pain Receptors

Receptors found throughout the body, but not in the brain, that detect injury or damage.

Central Nervous System (CNS)

Consists of the brain and spinal cord; it processes information, makes decisions, and coordinates responses.

Peripheral Nervous System (PNS)

Consists of all nerves outside the CNS and connects the CNS to the rest of the body.

Somatic Nervous System

A division of the PNS that controls voluntary skeletal muscles.

Autonomic Nervous System

A division of the PNS that controls involuntary actions of internal organs.

Cerebrum

The largest part of the brain responsible for thinking, memory, speech, senses, and voluntary movement.

Cerebellum

Part of the brain responsible for balance, coordination, and muscle control.

Brain Stem

Part of the brain that controls survival functions such as breathing, heartbeat, and digestion.

Neuron

A specialised cell that transmits messages throughout the body.

Dendrites

Parts of a neuron that receive messages.

Cell body

The part of a neuron that contains the nucleus.

Axon

The part of a neuron that carries messages away from the cell body.

Myelin sheath

The substance that insulates the axon of a neuron.

Sensory Neuron

A neuron that carries impulses from receptors to the Central Nervous System.

Interneuron

A neuron that carries impulses within the Central Nervous System.

Motor Neuron

A neuron that carries impulses from the Central Nervous System to effectors such as muscles or glands.

Synapse

The gap between neurons where signals pass from one cell to the next.

Neurotransmitters

Chemical signals released by a neuron to transmit a message across a synapse.

Reflex actions

Fast, automatic responses that do not require conscious thought.

Homeostasis

The process of maintaining a stable internal environment.

Negative Feedback

A primary mechanism of homeostasis where the response reverses a change to bring conditions back to normal.

Insulin

A hormone released by the pancreas when blood glucose is too high to help cells absorb glucose.

Glucagon

A hormone released by the pancreas when blood glucose is too low to cause the liver to release stored glucose.

Thermoregulation

The process of maintaining body temperature around $37\,^{\circ}\text{C}$.

Hypothalamus

The part of the brain that acts like the body's thermostat to regulate temperature.

Hormone

A chemical messenger produced by endocrine glands and carried in the blood to act on specific target cells.

Endocrine System

The body's chemical communication system which creates slower but longer-lasting responses compared to the nervous system.

Type 1 Diabetes

An autoimmune disease where the pancreas cannot produce insulin, requiring daily insulin intake.

Type 2 Diabetes

A condition often linked to lifestyle factors where cells become resistant to insulin and glucose builds up in the blood.

Motor Neuron Disease

A disorder that destroys motor neurons over time, resulting in the loss of muscle movement while sensory neurons remain functional.

Stem Cells

Cells that can develop into many different cell types, currently being researched for repairing damaged nerves.

Brain-Computer Interfaces

Devices that read brain signals to allow individuals to control computers or wheelchairs using only their thoughts.

Cochlear Implants

Electronic devices that stimulate the auditory nerve to assist people with hearing loss.