Brain Flashcards
The brain has a protective barrier called the Blood-Brain Barrier (BBB) that separates……
that separates the central nervous system from the peripheral tissues.
Blood brain barrier structure and functions
Structure
The blood-brain barrier has tight junctions that seal the endothelial cells of brain capillaries and a thick basement membrane that surrounds the capillaries.
Astrocyte processes contact the capillaries and maintain the permeability of tight junctions.
Function
The BBB’s function is to protect against proteins, antibiotic drugs and toxins but is permeable to:
Water-soluble substances e.g glucose
Ions, creatinine, urea
Lipid-soluble substances e.g. oxygen, carbon dioxide, alcohol, anaesthetic agents
Cranial meninges are membranous coverings that surround the brain.
Describe structure and function?
They consist of three layers:
Dura mater (outer) Arachnoid mater (middle) Pia mater (inner)
Function
Cranial meninges function as mechanical protection of the brain. Furthermore, they provide a supportive framework for the cerebral blood vessels.
The cerebrospinal fluid (CSF) is a liquid layer that protects the brain (and spinal cord) from chemical and physical injuries.
Structure and Function?
Structure
A clear, colourless liquid
The total volume within the brain is 80 - 150ml
Composed of water, glucose, proteins, lactic acid, urea, cations, anions and white blood cells
Contained within subarachnoid space (space between arachnoid mater and pia mater) and 4 ventricles (cavities within the brain)
Function Mechanical protection (serves as a shock absorber) Homeostatic function (affects pulmonary ventilation and cerebral blood flow) Circulation (a medium for the exchange of nutrients and waste products)
Which cell produces cerebrospinal fluid?
The cerebrospinal fluid is produced by specialised ependymal cells in the choroid plexuses of the ventricles of the brain and absorbed in the arachnoid granulations.
Which cells contribute to the blood-brain barrier?
Astrocyte processes contact the capillaries and maintain the permeability of tight junctions.
The cerebrum is the “seat of intelligence”; it provides us with the ability to read, write, and speak; to make calculations and compose music; to remember the past and plan for the future; and to create.
Structure-
Region of grey matter forms the outer rim Billions of neurons arranged in layers Gyri (folds) Sulci (shallow grooves between folds) Fissure (deep grooves between folds) Cerebral White Matter
Region of white matter beneath the cerebral cortex
Composed of myelinated neurons
The basal nuclei (formerly known as basal ganglia) is a region located at the base of the brain and composed of nuclei (= collection of cell bodies in the CNS). This area of the brain is responsible for body movement and coordination.
Structure and Function
Structure
There are three paired masses of grey matter (cell bodies):
Globus pallidus
Putamen
Caudate nucleus
The lentiform nucleus is a collective name given to the putamen and globus pallidus.
The lentiform nucleus and the caudate nucleus make up the corpus striatum.
Function
Regulate initiation and termination of movement
Control subconscious, skeletal muscle contraction
Initiate & terminate cognitive processes
Regulate emotional behaviours (with the limbic system)
The limbic system is a set of structures in the brain that supports emotions and memory.
Structure and Function
Structure
Ring of structures on the inner border of the cerebrum
Composed of multiple structures e.g. hippocampus, amygdala, olfactory bulbs
Function
Plays a primary role in emotions i.e pain, pleasure, docility, affection, anger
Olfaction (smell)
Memory
4 major structures of the brain
Cerebrum
Cerebrum
(Cerebral cortex and cerebral white matter)
4 hemispheres
3 functional areas- sensory, association and motor
4 major structures of the brain
Cerebrum
Diencephalon
Brain stem
Cerebellum
Diencephalon
Thalamus
Hypothalamus
Brain stem
Mid brain
Pons
Medulla oblangalla
