Lab 3a - Central Nervous System Flashcards
cephalo-, crani-
head
cerebro-, encephalo-
brain
neur-
nerve
optic-, opt-
eye
ot-, auri
ear
What are the embryonic germ cell layers?
Endoderm
Mesoderm
Ectoderm
What is the Endoderm?
- Innermost lining of cells in developing fetus
- from two “tubes” (digestive and respiratory)
- form gastrointestinal system, lungs, thyroid cells, and pancreatic cells
What is the Mesoderm?
- Middle layer
- Gives rise to skeletal muscles, repro structures, bones, and connective tissues
What is the Ectoderm?
- Outermost Layer
- Gives rise to the epidermis and almost all nervous syst.
Extodermal derived nervous syst develop from what?
- Primordial “Spinal Cord”
- Forms during dorsum of embryo
Cells of Neural tubes become what?
- The Central Nervous System (CNS)
- Brain/Spinal Cord
Neural Crest Cells become what?
- The peripheral nervous system (PNS)
- Other cell types
What is the PNS?
- Nerve fibers and cell bodies outside the CNS
- Somatic and visceral sensory neurons
What is the Somatic Nervous System?
- Elements under voluntary control
What is the Autonomic system?
- Governs “automatic” physiological responses
What two elements is the Autonomic Nervous System broken down into?
- Parasympathetic System
- Sympathetic System
What is the Parasympathetic System?
- Governs “vegetative” functions
- digestion and homeostatic maintenance
What is the Sympathetic System?
- Governs the “fight or flight” stress response
What is Gray Matter?
- Cell bodies, nuclei, and dendrites of nerve cells (neurons) and unmyelinated axons
- Forms cortex over cerebrum
- Surrounded by white matter
What is White Matter?
- High concentration of myelinated axons
The brain is divided into what parts?
- Cerebrum
- Cerebellum
- Brainstem
What are Ventricles (brain)?
- Brain contains 4 ventricles
- Filled with cerebrospinal fluid
- Derived from lumen of embryonic development
What are Meninges?
- Connective tissue membranes that surround the brain and spinal cord
- Lie between nervous tissue and bones
What are the cell types in nervous tissue?
- Neurons
- Glial Cells
What are Neurons?
- Nerve Cells
- Conduct nerve impulses
What are Glial Cells?
-Supporting
- Provide nutrition, support, establish blood-brain barrier
- Make myelin sheath around axon of neruons
What is the Cerebrum?
- Responsible for higher mental functions
- Contains both gray and white matter
- Divided into 2 hemispheres
- Contains paired lobes
What are the Cerebral Lobes?
- Frontal Lobe
- Parietal Lobe
- Temporal Lobe
- Occipital Lobe
- Insula
What is the Frontal Lobe?
- Responsible for voluntary motor control, reasoning, planning, emotions and social judgment
What is the Parietal Lobe?
- Perceives sensations from skin, muscle, tendons and joint receptors
What is the Temporal Lobe?
- Contains auditory centers
- Important in Memory
What is the Occipital Lobe?
- Responsible for vision and eye coordination
What is the Insula?
- Integrates sensory info. from viscera
- Roles in taste and language function
- Located in middle of brain where all Frontal, Parietal, and Temporal lobes meet
- Cannot be seen externally
What is the Corpus callosum?
- Band of nervous tissue that connects the two haves of the cerebrum
- Carries nerve impulses between 2 hemispheres
What is the Thalamus?
- Relay center for sensory info. (no smell)
- Walls of 3rd ventricle make up thalamus
- Filled with cerebral spinal fluid
What is the Hypothalamus?
- Regulates types of behavior
- Includes:
- Thirst/Hunger
- body temp
- Sleep/wakefulness
- Sexual Arousal
- Anger/fear/pain/pleasure
- Produce ADH, oxytocin, releasing and inhibitory
hormones that regulate the pituitary
What is the Pituitary Gland?
- AKA Hypophysis
- Compromised of 2 parts:
- Anterior Pituitary
- Posterior Pituitary
What is the Anterior Pituitary gland?
- Secretes somatotropin (GH, TSH, ACTH, FSH, LH, and Prolactin)
- regulated by releasing and inhibiting hormones secreted by the hypothalamus
- carried in the blood through the Hypothalamic_hypophyseal portal system
What is the Posterior Pituitary Gland?
- Released ADH and Oxytocin (nervous stimuli)
- Produced in Hypothalamus
Where does the pituitary gland sit and what is it protected by?
- Base of the brain
- Protected by sella turcica and sphenoid bone
What is the Optic chiasm?
- Optic nerves cross over on the way to brain from eyes
What is the limbic system?
- Part of the forebrain that processes olfactory info.
- Neural basis of emotional states
What parts form the limbic system?
- Hypothalamus
- Fornix encircle
What is the Cerebellum?
- 2nd largest part of brain
- Consists of gray and white matter
- Receives input from joint, tendon, and muscle receptors
- Responsible for coordination and movement
What is the Brainstem made up of?
- Midbrain
- Pons
- Medulla Oblongata
What does the Midbrain do?
- Connects to hindbrain and forebrain
- Controls brain receptors to stimuli, eye movement, and vocalization
What does the Pons do?
- Contains 2 respiratory centers
- Pathway for nerve fibers passing thru brain to spinal cord
What does the Medulla Oblongata do?
- Contains cell bodies of several cranial nerves
- Regulation of several autonomic systems
- Vasomotor center
- Cardioinhibitory center
- Respiratory Center
What is the Vasomotor center?
- Contraction or dilation of BV
- Regulates blood pressure
What is the Cardioinhinitory Center?
- parasympathetic innervation of the heart
- Regulates Heart rate
What is the Respiratory Center?
- Works w/ Respiratory Centers in pons to control respiration rate
What are cranial nerves?
- Nerves that run directly to the brain rather than thru the spinal cord
How many pairs of Cranial Nerves are there?
- 12 numbered with roman numerals
What are mixed nerves?
- Have both sensory and motor functions
What is the Vagus Nerve (X)?
- functions in salivation from parotid gland, swallowing, and phonation
What is the Optic Nerve (II)?
- Sensory-only nerve
- Carries impulses from eyes to occipital lobes
How many Spinal nerves are there?
- 31 pairs of nerves in human
- All are MIXED NERVES
