bio 221 functions

Central Nervous System (CNS)

Consists of the brain and spinal cord; interprets incoming sensory information and issues instructions based on past experience.

Peripheral Nervous System (PNS)

Consists of cranial and spinal nerves, ganglia, and sensory receptors; sends information to and from the CNS.

Cerebral Hemispheres

Right and left superior portions of the brain.

Cortex

Outer portion of the brain made up of grey matter.

Gyri

Elevated ridges of tissue in the brain.

Sulci

Shallow grooves next to the gyri, containing blood vessels.

Fissures

Deep grooves in the brain.

Longitudinal fissure

Divides the brain into right and left hemispheres.

Central sulcus

Separates the frontal and parietal lobes as well as separating the motor function from the sensory function

Postcentral Gyrus

Area behind the central sulcus associated with primary somatosensory functions; sensory information will come from all over the body such as for pain, temperature and pressure

Precentral Gyrus

Area in front of the central sulcus associated with primary motor functions; Primary Motor which is responsible for voluntary movement of skeletal muscle

Broca’s area

Specialized motor speech area located at the base of the precentral gyrus, usually on the left side.

Prefrontal Cortex

Anterior portions of the frontal lobes involved in intellect, complex reasoning, and personality.

Occipital Lobe

Part of the brain associated with vision.

Temporal Lobe

Part of the brain associated with hearing.

Olfactory Bulbs and tracts

Structures associated with the sense of smell.

Optic Nerve

Nerve responsible for vision.

Optic Chiasma

Point where the medial optic fibers cross.

Pituitary Gland

An endocrine gland that produces various hormones.

Cerebellum

Part of the brain involved in the unconscious coordination of skeletal muscle activity and control of balance.

Thalamus

Major integrating and relay station for sensory impulses.

Hypothalamus

Regulates body temperature, water balance, fat and carbohydrate metabolism, hunger, and thirst.

Pineal Body

Secretes melatonin, a hormone associated with sleep and wake cycles.

Cerebral aqueduct

Slender canal connecting the third and fourth ventricles.

Arbor Vitae of the Cerebellum

White matter within the cerebellum.

Meninges

Covers and protects the brain and spinal cord.

Dura Mater

Outer most meninx that is leathery.

Arachnoid Mater

Middle meninx that has arachnoid villi.

Pia Mater

Delicate inner most layer next to the brain and spinal cord.

Cerebrospinal Fluid (CSF)

Fluid that circulates in the subarachnoid space to protect the brain.

Olfactory

Nerve responsible for the sense of smell

sensory

Optic

Nerve responsible for vision.

sensory

Oculomotor

Nerve responsible for eye movement.

motor

Trochlear

Nerve responsible for eye movement.

motor

Trigeminal

Nerve responsible for chewing

both

Abducens

Nerve responsible for eye movement.

motor

optic tract

after the chiasma composed of medial fibers from the opposite eye and

lateral fibers from the same side.

Mammillary Body

relay station for olfaction.

Cerebral peduncles

fiber tracts in the midbrain connecting the pons below with the

cerebrum above

Pons

raised area just after the peduncles. means “bridge” and consists

primarily of motor and sensory fiber tracts connecting the brain with lower CNS centers.

Medulla Oblongata

lowest brain stem region; also composed of fiber tracts. also houses many vital autonomic centers involved in the control of heart rate, respiratory rhythm, and blood pressure as well as involuntary centers involved in vomiting and swallowing.

Corpus callosum

connects the right and the left hemispheres; forms the top of the

lateral ventricles

lateral ventricle

space between the corpus callous and the fornix

Choroid Plexus

bundle of capillaries found in the ventricles. They are surrounded by

epideminal cells and produce CSF

Fornix

bandlike fiber tract that makes the floor of the lateral ventricle; associated with

olfaction and the limbic system (emotions).

Septum pellucidum

the membrane that separates the right and left lateral ventricle.

This will only be seen if the brain is cut just right and hasn’t been torn up with probes!

Third Ventricle

space surrounding the thalamus and below the fornix

Superior colliculi

visual reflex center; Just below the pineal body

inferior colliculi

auditory reflex center; below the superior colliculi

Arbor Vitae of the Cerebellum

“Tree of Life”

white matter within the cerebellum

step one of CSF

lateral ventricle

step 2 of CSF

lateral ventricles to interventricular foramen

step 3

intercentricular formamen to third ventricle

step 4 of CSF

third ventricle to cerebral aqueduct

step 5 of CSF

cerebral aqueduct to fourth ventricle

step 6 of CSF

fourth ventricle to central canal or it will leave thru the medial and lateral apperatures subarachnoid space

step 7 of CSF

subarachnoid space or central canal to arachnoid villi

step 8 of CSF

arachnoid villi to dural sinus

step 9 of CSF

dural sinus to venous blood