Sensory Organs and Brain Structures

Vocabulary practice flashcards covering brain regions, anatomical structures, meningeal layers, and the sensory anatomy of the eye and ear.

Grey matter

Brain tissue that conducts actions, exemplified by the cerebral cortex.

White matter

Nervous tissue that communicates between instances of grey matter, exemplified by the myelin sheath.

Cerebrum

The major brain region making up the bulk of the brain, divided into left and right cerebral hemispheres and four lobes named after skull bones.

Gyri

The raised folds or ridges of the brain surface separated by sulci.

Sulci

The grooves or indentations that separate the gyri of the brain.

Fissure

A deeper brain sulcus, such as the longitudinal fissure that separates the left and right cerebral hemispheres.

Cerebral cortex

The most superficial layer of the cerebrum composed of grey matter that conducts many actions caused by the brain.

Corpus callosum

A central mass of white matter responsible for connecting and relaying communications between the left and right cerebral hemispheres.

Cerebellum

Brain structure located caudoventral to the cerebrum consisting of left and right cerebellar hemispheres.

Pons

The largest bump of the brain stem that connects, communicates, and relays information between the two cerebellar hemispheres.

Cerebellar cortex

The superficial grey matter layer of the cerebellum surrounding its internal white matter.

Diencephalon

Brain region containing the thalamus, hypothalamus, and the posterior pituitary gland.

Thalamus

A diencephalon structure appearing egg-shaped in medial view, but actually shaped like two eggs connected together by a bar.

Hypothalamus

Brain structure found ventral to the thalamus that assumes an unconventional triangular shape.

Pituitary glands

Endocrine glands located ventral to the hypothalamus consisting of anterior and posterior lobes, with only the posterior lobe technically being part of the diencephalon.

Brain stem

Structure composed of three sections from superior to inferior: midbrain, pons, and medulla oblongata.

Midbrain

The section of the brain stem located immediately superior to the pons.

Medulla oblongata

The section of the brain stem located immediately inferior to the pons that becomes continuous with the spinal cord after passing the magnum foramen.

Meninges

Protective coverings of the brain and spinal cord composed of three layers (dura mater, arachnoid mater, pia mater) and two cavities (subdural cavity, subarachnoid cavity).

Ora serrata

The serrated perimeter layer that connects the retina to the ciliary body, blocked from frontal view by the iris.

Tapetum lucidum

A layer of reflective tissue situated between the retina and choroid in most animals, prominent in nocturnal animals to facilitate night vision.

Nictitating membrane

The third eyelid located at the medial canthi of the eye.

Lacrimal glands

Tear-producing glands found at the dorsolateral eyelid.

Canthi

The medial and lateral corners of the eye.

Auditory ossicles

The three small bones of the middle ear: the malleus, incus, and stapes.

Vestibule

A structure of the internal ear that contains the utricle and saccule.

Cochlea

The coiled internal ear organ that contains the organ of Corti.