Lecture 5-8 Flashcards
Define Saggital plane
A cut right between the eyes, a side view of the brain
Define contralateral
Structures on the opposite sides of the body
Define Ipsalateral
Structures on the same sides of the body
Define deep and superficial
Away from surface, close to surface
What is CNS made of
Brain and Spinal Cord
What is PNS made of
Anything apart from brain and spinal cord
What is the main difference between Schwann cells and Oligodendrocytes
Schwann cells are found in the PNS and only produce myelin sheath for one axon at a time, whereas Oligodendrocytes are found in the CNS and produce myelin sheath for multiple axons at a time
What is lymp, how is it made, and what are its functions
Lymph is extracellular fluid of the body that leaks out of small holes in blood vessels, it flows around cells collecting waste and providing nutrients.
What are lymph nodes for
Lymph nodes is where lymph ends up, any collected waste and/or debris is broken down, after it is done, lymph is returned to the blood
What is blood brain barrier?
It is a property of blood vessels in the brain. Unlike ones in PNS, brain blood vessels do not have small holes that leak lymph. Brain takes any necessary nutrients from the blood by itself.
What is the alternative for lymph produced by the brain?
Cerebrospinal Fluid
What are the three meninges? What are their functions and properties
Dura mater is the outer layer, it is thick and tough unstretchable tissue. Arachnoid membrane is soft and spongy middle layer. Pia mater is the space that has blood vessels in it and sits closest to the brain
Where is CSF made?
In choroid plexus, tissue that is found in each of four brain ventricles
Where are lateral ventricles found?
Underneath the cerebrum
Where is the third ventricle located
Between the two thalamic nuclei
Where is the fourth ventricle found?
Between the pons and cerebellum
What is cerebral aqueduct and what does it connect?
It is a long tube-like structure that connects the third and fourth ventricle.
What are efferent fibers and what type of neurons is considered efferent
Efferent fibers are fibers that bring information away from the Central Nervous system. The soma of motor neurons is located in the spinal cord and sends info away from CNS
What arte afferent fibers and what type of neurons is considered afferent
Afferent fibers are fibers that bring information towards the Central Nervous System. Sensory neurons are considered afferent for they bring sensory info towards the CNS
How many pairs of spinal nerves are there and how do they attach to the spinal cord
There are 31 pairs of spinal nerves, 1 pair for each vertebrae
How many cranial nerves are there and where do they attach
There are 12 cranial nerves that attach to the ventral part of the brain
What are the functions of cranial nerves? What is the exception?
Cranial nerves are responsible for sensory and motor function in the face and neck area. The exception is 10th cranial nerve called vagus which is responsible for regulating functions in the abdominal area
Why is gray matter gray?
Because it is made up of cell bodies
Why is white matter white?
Because it is made of myelinated axons
What is somatic nervous system responsible for?
It is responsible for controlling skeletal and muscle movements and processing sensory information that relates to the outside world. Generally somatic ns senses and interacts with the external environment
What is autonomic nervous system responsible for? What are its divisions?
It is responsible for sensaton and regulation of smooth muscle, cardiac muscle, and glands. ANS generally interacts with body’s internal environment. It further splits into sympathetic and parasympathetic divisions
What is the role of Sympathetic division of ANS?
Priming body for fight or flight, it is always active to some extent for it controls blood circulation, heart rate, and almost every organ in the body, but when the threat is present, it shuts down every organ that is not crucial for survivial.
What is the role of Parasympathetic division?
It is responsible for regulating processes that occur when the body is in its relaxed state, mate and digest, responsible for sexual arousal, urination, defecation etc etc
What are the three major divisions of the human brain?
Hindbrain, Midbrain, Forebrain
What is the most caudal part of the brain stem called?
Medulla Oblongata
What is the role of Medulla
Regulating different autonomic functions such as heart rate, blood flow, breathing, etc.
In what area of medulla is blood brain barrier noticeably weak? What happens if poisons are detected in that area?
Area postrema. Brain will initiate vomiting reflex
What is retucilar formation important for?
Sleep and Arousal
What is the role of Pons?
Relaying information between the cerebrum and cerebellum.
What is the role of cranial nerve nuclei that are found in pons?
They participate in hearing, balance, taste, sensations and movements of the face
What is the role of cerebellum?
Motor control. it does not initiate movement, but contributes to its coordination, precision and accurate timing. It integrates sensory info and motor commands to exert a coordinating and smoothing effect on movement and cognition. It also plays an important pole in motor learning, especially when body grows and changes/
What type of cell division do neural progenitor cells exhibit during the first 40 days after conception?
Symmetrical cell division, one cell becomes two of the same type
What type of cell division do neural progenitor cells exhibit after the first 40 days after conception? How long does this period of division last for?
Asymmetrical cell division, the cell creates one neural progenitor cell and either one neuron or glial cell. It last for 85 days
Define neurogenesis
Production of new neurons by neural progenitor cells
Define apoptosis
Programmed cell self-destruction