Human Anatomy and Physiology

SciOly - Nov 2025

Action Potential

A rapid, short

Adrenal Gland

Endocrine gland that secretes hormones regulating stress response and metabolism.

Alzheimer's Disease

A neurodegenerative disease that causes progressive memory loss and cognitive decline.

Amine Hormone

A hormone derived from a single amino acid; can bind to either receptor type.

Amyotrophic Lateral Sclerosis (ALS)

A progressive neurodegenerative disease that affects motor neurons.

Anatoxin

a

Anosmia

Loss of the sense of smell.

Anterior Cerebral Artery (ACA)

Supplies blood to the anterior portions of the brain, including the frontal lobe.

Anterior Inferior Cerebellar Artery (AICA)

Supplies blood to the anterior inferior cerebellum and parts of the pons.

Ascending Tract

A pathway in the spinal cord that carries sensory information to the brain.

Astigmatism

Blurred vision caused by an irregularly shaped cornea or lens.

Basilar Artery

Artery formed by the fusion of the vertebral arteries; supplies the brainstem and cerebellum.

Bitemporal Hemianopia

Vision loss in the temporal fields of both eyes, often due to optic chiasm damage.

Botulinum Toxin

A neurotoxin that prevents the release of acetylcholine, causing muscle paralysis.

Brainstem

Connects the brain to the spinal cord; controls basic life functions.

Central Diabetes Insipidus

Condition caused by insufficient ADH production, leading to excessive urination.

Central Nervous System (CNS)

The brain and spinal cord; the control center of the nervous system.

Cerebellum

The "little brain," coordinates movement, balance, and posture.

Cerebral Palsy

A group of disorders that affect muscle movement and coordination.

Cerebrum

The largest part of the brain, responsible for higher

Circle of Willis

An interconnected group of arteries at the base of the brain.

Cochlea

A spiral

Color Blindness

Inability to distinguish certain colors.

Cone

Photoreceptor cell in the retina responsible for color vision.

Congenital Iodine Deficiency Syndrome

Condition caused by iodine deficiency during pregnancy, affecting fetal development.

Conjunctivitis

Inflammation of the conjunctiva (pink eye).

Cornea

The transparent outer layer of the eye that helps focus light.

Cranial Nerve

A nerve that originates directly from the brain or brainstem.

Curare

A plant toxin that blocks acetylcholine receptors, causing muscle paralysis.

Cytoplasmic Receptor

Receptor in the cell cytoplasm/membrane that initiates a signaling cascade.

Descending Tract

A pathway in the spinal cord that carries motor commands from the brain to the body.

Diabetes Mellitus

Metabolic disorder characterized by high blood sugar levels.

Diabetic Retinopathy

Damage to the blood vessels in the retina caused by diabetes.

Dysgeusia

Distorted sense of taste.

Dysosmia

Distorted sense of smell.

Ear Canal

The tube that carries sound waves from the pinna to the eardrum.

Eardrum (Tympanic Membrane)

Vibrates in response to sound waves, transmitting them to the ossicles.

Edinger

Westphal Nucleus

Encephalographic Waveform

A pattern of electrical activity in the brain, recorded by an EEG.

Epilepsy

A neurological disorder characterized by recurrent seizures.

Glaucoma

Damage to the optic nerve, often caused by increased eye pressure.

Glial Cell

A non

Goiter

Enlargement of the thyroid gland.

Goldman

Hodgkin

Gonad

Ovary or testis; produces sex hormones.

Graves' Disease

Autoimmune disorder causing hyperthyroidism.

Gustatory Nerve

Transmits taste information from the tongue to the brain.

Hair Cell

Sensory receptor cell in the inner ear that detects sound or changes in head position.

Hashimoto's Disease

Autoimmune disorder causing hypothyroidism.

Homonymous Hemianopia

Vision loss in the same half of the visual field in both eyes.

Hyperopia

Farsightedness; difficulty seeing close objects clearly.

Hyperparathyroidism

Excessive parathyroid hormone (PTH) production, leading to high calcium levels.

Hypersecretion

Excessive hormone production.

Hypersensitivity

Increased responsiveness to a hormone.

Hyperthyroidism

Excessive thyroid hormone production.

Hypoglycemia

Low blood sugar levels.

Hypoparathyroidism

Insufficient parathyroid hormone (PTH) production, leading to low calcium levels.

Hyposecretion

Insufficient hormone production.

Hyposensitivity

Decreased responsiveness to a hormone.

Hypothalamus

Brain region controlling hormone release from the pituitary gland.

Hypothyroidism

Insufficient thyroid hormone production.

Internal Carotid Artery

Major artery supplying blood to the brain; branches into ACA and MCA.

Iris

The colored part of the eye that controls the size of the pupil.

Lateral Geniculate Nucleus (LGN)

A relay center in the thalamus for visual information.

Lens

Focuses light onto the retina; its shape is adjusted by muscles.

Macular Degeneration

Deterioration of the macula, leading to central vision loss.

Membrane Potential

The voltage difference across a cell membrane due to ion concentration differences.

Meniere's Disease

Inner ear disorder causing vertigo, tinnitus, and hearing loss.

Middle Cerebral Artery (MCA)

Supplies blood to a large portion of the lateral brain surface.

Miosis

Pupillary constriction.

Monocular Blindness

Blindness in one eye.

Motor Neuron

A neuron that transmits signals from the CNS to muscles or glands.

Multiple Sclerosis

An autoimmune disease that damages the myelin sheath of nerve fibers.

Mydriasis

Pupillary dilation.

Myelination

The process of insulating a nerve axon with a myelin sheath to increase speed.

Myopia

Nearsightedness; difficulty seeing distant objects clearly.

Nasal Cavity

The hollow space inside the nose where air is warmed and filtered.

Nerve Root

The initial segment of a spinal nerve as it exits the spinal cord.

Neural Ganglion

A cluster of nerve cell bodies in the peripheral nervous system.

Neuron

A nerve cell that transmits electrical and chemical signals; the basic unit of the nervous system.

Neurotransmitter

A chemical messenger that transmits signals across a synapse.

Nuclear Receptor

Intracellular receptor that, when bound to a hormone, affects gene transcription.

Nyctalopia

Night blindness; difficulty seeing in low light.

Oculomotor Nerve

Cranial nerve that controls pupillary constriction and other eye movements.

Olfactory Bulb

A brain structure that receives signals from olfactory receptor cells.

Olfactory Epithelium

A layer of tissue in the nasal cavity containing olfactory receptor cells.

Olfactory Receptor Cell

Neurons in the nasal cavity that detect odor molecules.

Optic Chiasm

The point where the optic nerves cross in the brain.

Optic Nerve

Transmits visual information from the retina to the brain.

Optic Tract

Nerve fibers carrying visual information from the optic chiasm to the brain.

Ossicle

Small bones in the middle ear (malleus, incus, stapes) that amplify sound vibrations.

Otitis Externa

Infection of the outer ear canal (swimmer's ear).

Otitis Media

Infection of the middle ear.

Otosclerosis

Abnormal bone growth in the middle ear, leading to hearing loss.

Pancreas

Endocrine gland that secretes insulin and glucagon, regulating blood sugar.

Papilla

Small bumps on the tongue that contain taste buds.

Parasympathetic Nervous System

The "rest and digest" system; conserves energy and maintains normal function.

Parathyroid

Endocrine gland that secretes parathyroid hormone (PTH), regulating calcium levels.

Parkinson's Disease

A neurodegenerative disorder that affects movement, causing tremors and rigidity.