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A process where organisms better suited to their environment are more likely to survive and reproduce, passing beneficial traits to their offspring.

A change in a gene's DNA sequence that can affect an organism's traits.

A genetic trait that provides an advantage in a specific environment.

A disease caused by a parasite transmitted through mosquito bites, often deadly in tropical climates.

A specific type of mutation where red blood cells become sickle-shaped, affecting oxygen transport.

An individual carrying a single copy of the sickle-cell gene, typically exhibiting mild symptoms or no symptoms.

An individual carrying two copies of the sickle-cell gene, experiencing severe symptoms and health problems.

The process where a mutation provides a survival advantage in a particular environment, increasing its prevalence in a population.

Specialized cells that support and protect neurons, providing essential functions such as scaffolding, insulation, nutrient transport, and immune responses.

The main functional unit of the nervous system; responsible for transmitting information throughout the body.

The outer layer of a neuron, selectively allowing certain molecules to pass through.

The central part of a neuron containing the nucleus and other essential structures.

Branching extensions of a neuron that receive signals from other neurons.

A long, slender projection of a neuron that transmits signals to other neurons.

Small structures at the end of an axon that release neurotransmitters to communicate with other neurons.

A fatty substance that coats some axons, providing insulation and increasing the speed of signal transmission.

A state of readiness in a neuron where it is not actively transmitting information. Maintaining a negative charge inside the cell compared to the outside due to the distribution of ions within the cell.

A critical threshold that a neuron must reach to become active and generate an electrical signal.

The rapid electrical signal transmitted down a neuron's axon. This signal carries information within the nervous system. It involves a surge of sodium ions entering the cell, making the inside more positive.

A rapid increase in the neuron's charge during the action potential, caused by a massive influx of sodium ions.

The process of restoring the neuron to its resting potential after an action potential. This happens by potassium ions moving out of the cell, making the inside more negative again.

A brief period after an action potential during which the neuron is less likely to fire another action potential. It helps control the rate of signal transmission.

Gaps in the myelin sheath that insulate the axon. These gaps allow the action potential to jump between Nodes of Ranvier, increasing the speed of signal transmission.

A specialized protein that lets ions pass through the neuronal membrane. When it opens, it allows ions to move in or out of the cell, contributing to the electrical signal.

The principle that a neuron either fires completely or not at all, with no partial firing.

The process where the action potential maintains its full strength as it travels down the axon.

The chemicals released from the terminal buttons of a neuron into the synaptic cleft, allowing communication between neurons.

The gap between the terminal button of one neuron and the dendrite of another neuron.

The process where neurotransmitters bind to receptors on the dendrite of the receiving neuron.

The process of removing excess neurotransmitters from the synaptic cleft.

A clear 'on' and 'off' state between signals, regulating the production of neurotransmitters.

Sensory neurons transmit information from sensory organs to the central nervous system (CNS).

Motor neurons carry signals from the CNS to muscles and glands, initiating actions.

The autonomic nervous system controls involuntary bodily functions like heart rate, breathing, and digestion.

The sympathetic nervous system prepares the body for 'fight or flight' responses to stress.

The parasympathetic nervous system calms the body and helps it return to its normal state after stress.

Homeostasis is the body's ability to maintain a stable internal environment despite external changes.

The fight or flight response is a physiological reaction to stress, preparing the body for action or escape.

Adrenaline plays a crucial role in the fight or flight response, increasing heart rate, blood pressure, and energy levels.

The brain area involved in processing touch, temperature, and pain. It maps different body regions to specific areas of the cortex, with more sensory-rich areas getting larger regions.

The brain lobe responsible for processing sensory information from your body, including touch, temperature, and pain.

The area responsible for processing sound information. It's located in the temporal lobe.

The region in the temporal lobe crucial for understanding speech. It helps you make sense of what you hear.

The brain lobe located on the side of the head, involved in hearing, memory, emotions, and some aspects of language.

The brain lobe responsible for higher-level cognitive functions, such as planning, decision-making, and personality.

The region in the frontal lobe responsible for personality, decision-making, and planning.

The specific brain injury suffered by Phineas Gage, involving damage to the prefrontal cortex, leading to significant personality changes.