Chapter 14: The Brain and Cranial Nerves Flashcards
the 4 major parts of the brain
the brain stem, diencephalon, cerebrum, and cerebellum
the development of the brain and spinal cord begins with…
the ectoderm begining as a hollow neural tube
The brain is protected by what 3 things?
cranial bones, cranila meninges (arachnoid, dura and pia matter), cerebrospinal fluid
Blood flows to the brain via…
the internal carotid and vertebral arteries
Blood from the brain to the heart flows via..
the jugular viens
protects brain cells from harmful substances and pathogens by serving as a selective barrier to prevent passage of many substances from the blood to the brain
The blood-brain barrier (BBB)
a clear, colorless liquid that protects the brain and spinal cord against chemical and physical injuries and carries oxygen, glucose, and other needed chemicals from the blood to neurons and neuroglia
cerebrospinal fluid (csf)
CSF is stored in…
4 ventricles in the brain
CSF is formed in…
The choriod plexus
CSF is continously absorbed by arachnoid villa in the sagital blood sinus to maintain constant _____ and _____
volume and pressure
continuous with the upper part of the spinal cord and contains portions of both motor and sensory tracts. Functional regions include nuclei that are reflex centers for regulation of heart rate, respiratory rate, vasoconstriction, swallowing, coughing, vomiting, sneezing, and hiccupping; the first three are considered vital reflexes
Medulla Oblongata
What are the two strcutural regions of the medulla oblongata?
the pyramids and the inferior ovilary neurons
Decussation of pyramids results in what?
neurons in the left cerebral cortex controlling skeletal muscles on the right side of the body and neurons in the right cerebral cortex controlling skeletal muscles on the left side
relay impulses from proprioceptors to the cerebellum.
inferior olivary neurons
What 3 things make up the brain stem?
medulla oblongata, pons, midbrain
located superior to the medulla. It connects the spinal cord with the brain and links parts of the brain with one another by way of tracts. It relays nerve impulses related to voluntary skeletal movements from the cerebral cortex to the cerebellum. Also helps control respiration
the pons
conveys motor impulses from the cerebrum to the cerebellum and spinal cord, sends sensory impulses from the spinal cord to the thalamus, and regulates auditory and visual reflexes
the midbrain
consists of small areas of gray matter interspersed among fibers of white matter and has both sensory and motor functions. It helps regulate muscle tone, alerts the cortex to incoming sensory signals and is responsible for maintaining consciousness and awakening from sleep
reticular formation
occupies the inferior and posterior aspects of the cranial cavity and consists of two hemispheres and a central, constricted vermis
the cerebellum
What attached the cerebellum to the brain stem?
3 cerebellar peduncles
functions in the coordination of skeletal muscle contractions and in the maintenance of normal muscle tone, posture, and balance
the cerebellum
located superior to the midbrain and contains nuclei that serve as relay stations for all sensory impulses, except smell, to the cerebral cortex
the thalamus
registers conscious recognition of pain and temperature and some awareness of light touch and pressure. Plays an essential role in cognition
the thalamus
is found inferior to the thalamus, has four major regions , controls many body activities, and is one of the major regulators of homeostasis
hypothalamus
What are the four regions of the hypothalamus?
mammillary, tuberal, supraoptic, and preoptic
What are the 3 parts of the diencephalon?
thalamus, hypothalamus, epithalamus
lies superior and posterior to the thalamus and contains the pineal gland and the habenular nuclei
the epithalamus
secretes melatonin to influence diurnal cycles in conjunction with the hypothalamus
pineal gland
located within the epithalamus these are involved in olfaction, especially emotional responses to odors
habenular nuclei
Parts of the diencephalon that can monitor chemical changes in the blood because they lack a blood-brain barrier
circumventricular organs (CVOs)
function to coordinate homeostatic activities of the endocrine and nervous systems
CVOs
