Brain Flashcards
What are the two subdivisions of nervous system and what kind of nerves do they have
Central nervous system includes brain and spinal cord. Peripheral nervous system has spinal nerves, cranial nerve, ganglia and sensory receptors
Describe the divisions of peripheral nervous system
Peripheral nervous system is divided into efferent and afferent division. Efferent division is divided into autonomic and somatic nervous system. Autonomic nervous system is divided into sympathetic and para sympathetic nervous system
What is enteric nervous system
The nervous system found any digestive tract
What are the parts of neurones
Neurones have a cell body, axons and dendrites
What does the cell body have
Cell body has lysosomes, mitochondria, golgi complex, free ribosomes and cluster of ER called nissle bodies
How does cell bodies occur in pns
They occur in clusters called ganglia
What is axon hillock
The part where the cell body and the axon meet
Why are the cytoplasm of the cell body is negatively charged
Because it has negatively charged protein
What does axon contains
It contains mitochondria microtubules and neurofibrils
Where are multipolar and bipolar neurones found
Multipolar neurones are found in brain and spinal cord, bipolar neurones are found in retina of the eye and olfactory areas of the brain
Why are unipolar neurons called pseudounipolar neuron.
Because they were bipolar in the beginning of the embryo
Which neuron act as a sensory receptors
Unipolar neurones
Function of glial cells
Glial cells help in feeding the neurons, filling the space and divide into mature neurons
Types of glial cells
There are four types of neuroglia in CNS: -
Astrocytes
Oligodendrocytes
Ependymal cells
Microglia
PNS
Schwann Cell
Satellite Cell
What factors affect the electrical transmission
Temperature, axon diameter, myelin sheath
What is the protective connective tissue in the cranium and its type
Meninges are protective connective tissue.
Dura matar, arachnoid matar and pia matar
What is the name of space between arachnoid matar and pia matar
Subarachnoid space and it has cerebrospinal fluid
What is the function of cerebrospinal fluid
It helps in transportation of Oxygen and glucose from blood to neurons. It acts as a shock absorbent.
What are ventricles
CSF fill the spaces in the brain called ventricles. They are of three types, two lateral ventricles, third ventricle and fourth ventricle.
What is blood brain barrier and how is it made
Blood brain barrier helps in filtering out pathogens and harmful substances from blood. It allows transportation of oxygen, carbon dioxide, lipid soluble molecules. It is made up of capillaries that are joint by tight junction
Three major parts of brain and their subtypes
Forebrain : Cerebrum and diencephelon (thalamus and hypothalamus)
Mid brain: tectum and tegmentum
Hind brain : cerebellum, medulla and pons
Corpus callosum
Mass of fibres in cerebrum
Gyri and sulci
Gyri are the fold and sulci are the depression
What is cerebral cortex
The thin outer layer covering of grey matter on the hemisphere
What are the deep sulci called
Fissure
Basal nuclei
The several masses of grey matter present in the white matter
Why does grey matter appear grey
Because nissle bodies impart grey colour
Division of cerebrum
Frontal lobe, parietal lobe, olfactory lobe and temporal lobe
What are the function of all the subtypes of cerebrum
Frontal lobe: voluntary activities, speaking ability and elaboration of thought
Parietal lobe: sensory information such as temperature, pain, touch, taste and information about numbers.
Temporal lobe : they help in processing memory and auditory information and speech and language function.
Occipital lobe: they receive and process visual information.
Three types of diencephelon
Eipthalamus, thalamus and hypothalamus
Thalamus function
It is situated between the cerebral cortex and midbrain. Sensory awareness of pain, temperature, and touch.
Function of hypothalamus
- Controls body temperature
- Uptake of water and food
- Controls anterior pituitary hormone secretion and secretes posterior pituitary hormone.
- Plays a role in habit and sleep.
- Plays a role in emotional and behavioural patterns.
What is the second largest part of the brain?
Cerebellum
Name the two parts of cerebellum
Cerebellar cortex and vermis
What is called tree of life? Where is it present?
Arbor vitae and it is present in the grey matter of the cerebellum.
Function of cerebellum
Helps in maintaining body posture, maintains muscle tone, voluntary muscle activities and balance.
It also has a role cognition and language processing.
Function of medulla.
Helps in regulating heartbeat, blood vessel diameter, normal heartbeat rhythm. The nucleus helps in vomiting, sneezing, coughing and hiccuping.
Function of pons
Facial muscle strength and eye muscle control
Function of limbic system
Regulation in sexual behaviour, emotion, long term memory and motivation.
Three prominent components of the limbic system
Cingulate gyrus, hippocampus and amygdala
How many spinal nerves are there
31 pairs
What are nerve ? What are they called in CNS
Bundle of axons that form fibre make nerve. They are called tracts in CNS
Where does the afferent and efferent neuron connect to the spinal cord?
Dorsal root and ventral root
What are the nucleus in CNS?
Nucleus are the densely packed cell bodies in the CNS
What does reflex arc consist?
Sensory receptor, sensory neuron, integrating centre, efferent neuron and effector organ.
How many cranial nerves are there?
12 pairs
What is the longest and shortest cranial nerve?
Longest: Vagus
Shortest: Trochlear
Parasympathetic division origin?
The preganglionic neuron originate in brain (brain stem) and sacral region.
Ganglion is present near the effector organ or in the effector organ
Sympathetic division origin?
Preganglionic neuron originate from cervical and thoracic region. Ganglion is present in the either side of spinal cord.
Which neuron releases Acetylcholine
Parasympathetic and sympathetic preganglionic neuron, and parasympathetic postganglionic neuron.
Which neuron releases norepinephrine
Sympathetic postganglionic neuron
Length of preganglionic neuron of parasympathetic and sympathetic division
Sympathetic: short preganglionic neuron
Parasympathetic: long preganglionic neuron
Which system is for flight and fight?
Sympathetic
Motor neuron axon secrete?
Acetylcholine
