Spinal Reflexes and the Nervous System

These flashcards cover key concepts related to spinal reflexes, the nervous system, and the endocrine system as discussed in the lecture.

Spinal Reflexes

Automatic responses to stimuli involving sensory neurons, interneurons, and motor neurons.

Sensory Neurons (Afferent)

Neurons that carry information from peripheral receptors to the central nervous system (CNS).

Motor Neurons (Efferent)

Neurons that carry commands from the CNS to peripheral effectors.

Reflex Arc

Pathway that mediates a reflex action, involving sensory neuron, interneuron (sometimes), and motor neuron.

Innate Reflexes

Inborn, automatic reflexes present at birth that are genetically programmed.

Acquired Reflexes

Learned reflexes developed after birth through experience and practice.

Somatic Reflexes

Reflexes that activate skeletal muscles and produce movement.

Visceral Reflexes

Reflexes that regulate internal organ functions, controlled involuntarily.

Monosynaptic Reflexes

Reflex arcs involving only one synapse between the sensory and motor neurons.

Polysynaptic Reflexes

Reflex arcs involving multiple synapses, sensory neurons, interneurons, and motor neurons.

Withdrawal Reflex

Protective reflex that removes the body from harmful stimuli, typically initiated by pain.

Crossed Extensor Reflex

Reflex that stabilizes the body upon withdrawal of a limb, contracting the opposite limb.

Babinski Reflex

Response to stroking the sole of the foot, indicating neurological function (positive in infants, abnormal in adults).

Nociceptors

Receptors responsible for detecting pain.

Thermoreceptors

Receptors that detect temperature changes.

Mechanoreceptors

Receptors that respond to mechanical deformation.

Spinothalamic Pathway

Pathway for pain and temperature that crosses over to the opposite side of the spinal cord.

Corticospinal Pathway

Main voluntary motor pathway, originating from the primary motor cortex.

Autonomic Nervous System (ANS)

Part of the nervous system that controls involuntary functions of the body.

Sympathetic Division

Part of ANS responsible for 'fight-or-flight' responses.

Parasympathetic Division

Part of ANS responsible for 'rest-and-digest' functions.

Epinephrine

Hormone released during stress that increases heart rate and blood pressure.

Acetylcholine (ACh)

Neurotransmitter used by the parasympathetic nervous system.

Hormones

Chemical messengers produced by glands in the endocrine system.

Insulin

Hormone produced by the pancreas that lowers blood glucose levels.

Glucagon

Hormone produced by the pancreas that raises blood glucose levels.

Cortisol

Hormone produced by the adrenal cortex involved in the stress response.

Feedback Regulation

Mechanism by which the endocrine system maintains homeostasis by adjusting hormone levels.

Diabetes Mellitus

Condition characterized by chronic hyperglycemia due to insulin deficiency or resistance.