Human Body Systems: Functions, Anatomy, and Nervous System Details

What is the primary function of the circulatory system?

To transport oxygen, nutrients, and waste throughout the body.

What is the main function of the respiratory system?

To exchange gases, taking in oxygen and removing carbon dioxide.

What is the function of the digestive system?

To break down food, absorb nutrients, and eliminate waste.

What is the function of the nervous system?

To control body activities and respond to internal and external stimuli.

What is the function of the muscular system?

To produce movement, maintain posture, and generate heat.

What is the function of the skeletal system?

To provide structure, protect organs, and produce blood cells.

What is the function of the endocrine system?

To secrete hormones that regulate body processes.

What is the function of the urinary system?

To remove waste from the blood and maintain water and electrolyte balance.

What is the function of the reproductive system?

To produce gametes and enable reproduction.

What is the function of the integumentary system?

To protect the body, regulate temperature, and sense stimuli.

What is the function of the lymphatic system?

To return fluid to the blood and fight infections.

What is anatomy?

The study of the structure of the body and its parts.

What is physiology?

The study of the functions of body parts and systems.

What is the difference between anatomy and physiology?

Anatomy is structure; physiology is function.

What is the smallest functional unit of the nervous system?

The neuron.

What are the main parts of a neuron?

Dendrites, cell body, axon, and synaptic terminals.

What is the function of dendrites?

To receive signals from other neurons.

What is the function of the axon?

To carry electrical impulses away from the cell body.

What is the function of the myelin sheath?

To insulate the axon and speed up signal transmission.

What is a synapse?

The junction between two neurons where signals are transmitted.

What is the main function of the central nervous system (CNS)?

To process information and coordinate body activities.

What is the main function of the peripheral nervous system (PNS)?

To transmit signals between the CNS and the rest of the body.

What are the two main divisions of the PNS?

Somatic and autonomic nervous systems.

What does the somatic nervous system control?

Voluntary movements of skeletal muscles.

What does the autonomic nervous system control?

Involuntary body functions like heart rate and digestion.

What are the two divisions of the autonomic nervous system?

Sympathetic and parasympathetic.

What is the role of the sympathetic nervous system?

To prepare the body for "fight or flight" responses.

What is the role of the parasympathetic nervous system?

To conserve energy and promote "rest and digest."

What is a reflex?

A rapid, involuntary response to a stimulus.

Where is the cerebrum located?

The upper part of the brain.

What is the main function of the cerebrum?

To control voluntary movements, reasoning, and senses.

Where is the cerebellum located?

Under the cerebrum at the back of the brain.

What is the function of the cerebellum?

To coordinate movement and maintain balance.

What is the brainstem responsible for?

Controlling basic life functions like breathing and heartbeat.

What is the function of the spinal cord?

To transmit signals between the brain and body.

What are the three types of neurons?

Sensory, motor, and interneurons.

What does a sensory neuron do?

Carries signals from the body to the CNS.

What does a motor neuron do?

Carries signals from the CNS to muscles or glands.

What does an interneuron do?

Connects neurons within the CNS.

What is the function of neurotransmitters?

To transmit signals across synapses.

Name a major neurotransmitter.

Examples: dopamine, serotonin, acetylcholine.

What is the function of acetylcholine?

To stimulate muscle contraction and transmit signals in the PNS.

What is the function of dopamine?

To regulate mood, movement, and reward pathways.

What is the function of serotonin?

To regulate mood, appetite, and sleep.

What is the difference between white and gray matter?

White matter contains myelinated axons; gray matter contains cell bodies.

What is the function of cerebrospinal fluid (CSF)?

To cushion the brain and spinal cord.

What is a nerve?

A bundle of axons in the PNS.

What is a ganglion?

A cluster of neuron cell bodies in the PNS.

What is a receptor?

A specialized structure that detects stimuli.

What is the function of the hypothalamus?

To regulate body temperature, hunger, and hormone release.

What is the function of the pituitary gland?

To secrete hormones that control other endocrine glands.

What is the function of the thyroid gland?

To regulate metabolism through hormone secretion.

What is the function of the adrenal glands?

To produce stress hormones like adrenaline and cortisol.

What is homeostasis?

The maintenance of a stable internal environment.

What is a negative feedback mechanism?

A process that reverses a change to maintain homeostasis.

What is a positive feedback mechanism?

A process that amplifies a change in the body.

Give an example of negative feedback.

Regulation of body temperature.

Give an example of positive feedback.

Blood clotting.

What is the difference between voluntary and involuntary actions?

Voluntary actions are consciously controlled; involuntary actions are automatic.

What is the main function of sensory receptors?

To detect changes in the environment and send signals to the CNS.

What are the five main senses?

Sight, hearing, taste, smell, touch.

What is the function of the retina?

To detect light and send visual signals to the brain.

What is the function of the cochlea?

To convert sound vibrations into nerve impulses.

What is the role of the olfactory receptors?

To detect odors.

What is the role of taste buds?

To detect flavors on the tongue.

What is the function of the skin in the nervous system?

To detect touch, pressure, temperature, and pain.

What is the difference between rods and cones in the eye?

Rods detect light and dark; cones detect color.

What is the role of the optic nerve?

To transmit visual information from the retina to the brain.

What is the function of the auditory nerve?

To transmit sound information from the cochlea to the brain.

What is the function of the somatosensory cortex?

To process touch and body sensation information.

What is the function of the motor cortex?

To control voluntary muscle movements.

What is the function of the limbic system?

To regulate emotions, memory, and motivation.

Name a part of the limbic system.

Examples: amygdala, hippocampus, hypothalamus.

What is the function of the hippocampus?

To form and store memories.

What is the function of the amygdala?

To process emotions like fear and pleasure.

What is the difference between short-term and long-term memory?

Short-term is temporary storage; long-term is permanent storage.

What is the function of the corpus callosum?

To connect the left and right hemispheres of the brain.

What is a nerve impulse?

An electrical signal transmitted along a neuron.

What is the resting potential of a neuron?

The electrical charge difference across the membrane at rest.

What is an action potential?

A rapid change in membrane potential that transmits a signal.

What is depolarization?

When the neuron's membrane becomes less negative, triggering an action potential.

What is repolarization?

When the neuron's membrane returns to its resting potential.

What is hyperpolarization?

When the neuron's membrane becomes more negative than the resting potential.

What is the all-or-none principle?

A neuron either fires completely or not at all.

What ion is responsible for depolarization?

Sodium (Na⁺).

What ion is responsible for repolarization?

Potassium (K⁺).

What is the refractory period?

The time during which a neuron cannot fire another action potential.

What is the difference between a neuron and a nerve?

A neuron is a single cell; a nerve is a bundle of axons.

What is the function of Schwann cells?

To form myelin in the PNS.

What is the function of oligodendrocytes?

To form myelin in the CNS.

What is the function of astrocytes?

To support neurons and maintain the blood-brain barrier.

What is the function of microglia?

To protect the CNS by acting as immune cells.

What is the function of ependymal cells?

To produce and circulate cerebrospinal fluid.

What is the difference between gray and white matter in the CNS?

Gray matter contains neuron cell bodies; white matter contains myelinated axons.

What is a nerve tract?

A bundle of axons in the CNS.

What is the function of the medulla oblongata?

To control autonomic functions like heartbeat and breathing.

What is the function of the pons?

To relay signals between the cerebrum and cerebellum.

What is the function of the midbrain?

To control vision, hearing, and motor control.

What is the role of sensory adaptation?

To decrease sensitivity to a constant stimulus.

What is the difference between afferent and efferent neurons?

Afferent neurons carry signals to the CNS; efferent carry signals from the CNS.