unit 1 Vocab Quiz 2: The Nervous System

nervous system

the body's speedy, electrochemical communication network, consisting of all the nerve cells of the peripheral and central nervous systems

central nervous system (CNS)

the brain and spinal cord

peripheral nervous system (PNS)

the sensory and motor neurons that connect the central nervous system (CNS) to the rest of the body

nerves

neural "cables" containing many axons and are part of the peripheral nervous system connecting the central nervous system with muscles, glands, and sense organs

sensory (afferent) neurons

neurons that carry incoming information from the sensory receptors to the brain and spinal cord

motor (efferent) neurons

neurons that carry outgoing info from the brain and spinal cord to the muscles and glands

interneurons

central nervous system neurons that internally communicate and intervene between the sensory inputs and motor outputs

somatic nervous system

the division of the peripheral nervous system that controls the body's skeletal muscles

autonomic nervous system

the part of the peripheral nervous system that controls the glands and the muscles of the internal organs

sympathetic nervous system

the division of the autonomic nervous system that arouses the body, mobilizing its energy in stressful situations

parasympathetic nervous system

the division of the autonomic nervous system that calms the body, conserving its energy

glial cells

cells in the nervous system that support, nourish, and protect neurons

endocrine system

the body's "slow" chemical communication system; a set of glands that secrete hormones into the bloodstream

hormone

Chemical messengers, mostly those manufactured by the endocrine glands, that are produced in one tissue and affect another

pituitary gland

The endocrine system's most influential gland. Under the influence of the hypothalamus, the pituitary regulates growth and controls other endocrine glands

Dopamine

A neurotransmitter involved in reward, motivation, and motor control

Acetylcholine (ACh)

A neurotransmitter involved in muscle activation, memory, and learning

Serotonin

A neurotransmitter that affects mood, appetite, and sleep

Norepinephrine

A neurotransmitter and hormone involved in arousal and alertness

GABA (Gamma-Aminobutyric Acid)

The main inhibitory neurotransmitter in the brain, which helps regulate neural activity and reduce anxiety (a natural tranquilizer)

Glutamate

The main excitatory neurotransmitter in the brain

Endorphins

Neurotransmitters that are natural painkillers produced by the brain

Reflex Arc

The neural pathway that controls a reflex action

Adrenaline

hormone and neurotransmitter that plays a key role in the body's stress response, often referred to as the "fight or flight" response

Ghrelin

hormone produced primarily by the stomach and small intestine that stimulates appetite and promotes hunger

Leptin

hormone produced primarily by fat cells that regulates energy balance and appetite. It acts on the hypothalamus in the brain to suppress appetite and increase energy expenditure

Melatonin

hormone that regulates the sleep-wake cycle and circadian rhythms in the body

Oxytocin

hormone and neurotransmitter that plays a key role in social bonding

opioids

A class of drugs that act on opioid receptors to produce morphine-like effects, including pain relief and feelings of euphoria

Alcohol

A depressant that slows down the central nervous system, impairing cognitive and motor functions

Caffeine

A stimulant found in coffee, tea, and many soft drinks that increases alertness and reduces fatigue

Cocaine

A powerful stimulant drug that increases levels of dopamine in the brain, leading to intense euphoria and increased energy

Marijuana

A drug containing THC that alters mood, perception, and cognitive function

Heroin

An opioid drug that produces intense euphoria and pain relief, highly addictive

addiction

A complex condition characterized by compulsive drug use or behaviors despite harmful consequences.

tolerance

The diminishing effect of a drug with regular use, requiring larger doses to achieve the same effect

withdrawal

The discomfort and distress that follow discontinuing the use of an addictive drug or behavior