midterm Flashcards
components of the central nervous system
brain, spinal cord
components of the peripheral nervous system
somatic nervous system, autonomic nervous system
components of the endocrine system
endocrine system, endocrine system with endocrine-like activity
components of the local support and defence system
- maintenance and support system
- adaptation ad repair system
- resident defence system
- migrant defence system
what is tissue
a group of similar cells that perform the same function
what is an organ
a structure with two or more tissues working together
what is the ccn
the logic unit of the human adult: the role of the network is to direct information flow in the system
properties of the ccn
- controls and coordinates the function of all physiological systems and individual organs
- network is always active
- the system is distributed throughout the body
- each component of the system has multiple functions
- information flow within the network is via chemical-based cell-cell communication
3 inputs to health, disease, aging=
7 outputs to health and wellness
examples with primary portion of the can affected
- diabetes, NAFLD, atherosclerosis (endocrine system)
- cancer, autoimmune diseases( local support and defence system)
- depression, ADHD (central nervous system)
example of diseases in endocrine system
diabetes, nafld
example of diseases in local support and defence system
cancer, autoimmune
example of diseases in central nervous system
depression, ADHD
a systems CNN/biology-based approach to health, disease, and ageing is anticipated to facilitate enhanced medical/ healthcare practices. How?
personalized, predictive, preventiticve, and participation
what is the limiting factor in medicine/ healthcare
participation
what is psoriasis
the body believes there is a would so cells grow like crazy
disease of the entire CCN, not just of the skin
describe the multi-layered, multi-dimensional approach to research
a) simulations with mathematic model systems (in silico)
b) invitro and ex-vivo models (cell cultures)
c) aminal models
d) people (human subjects)
what is in silico
simulations with mathematical models
what is in-vitro and ex-vivo
cell cultures and related techniques
what is non-intervention studies
subjects are not given a medicinal treatment
cannot be used to predict/prove cause and effect of a medicinal substance
describe intervention studies
clinical subjects are given a medicinal treatment or a control substance/placebo
by comparing data from the treatment and control groups, this type of experiment can be used to predict cause and effect
double-blind, placebo-controlled clinical trials are the most common category and are the gold standard for medical and healthcare research
animal ethics in Canada
canadian council on animal care
human ethics in Canada
the tri-council human ethics policy
two ways medicine is practiced
as preventative medicine or therapeutic medicine
what is intervention
physician-directed actions and activities in preventative medicine
describe evidence-based medicine
a) best approach to keep medical practices current
b) external appraisal of research studies
c) meta-analysis (the Cochrane collaboration)
d) evidence-based medicine outcome
describe the treatment algorithm
least invasive to most invasive
assess other risks/ factors
four types of medical and healthcare practices
evolutionary
integrative
collective
enhancement
describe collective medicine
can’t be healthy in a failing ecosystem
describe the scale of time 1
growth, development, ageing
life as a trajectory (years/decades)
describe the scale of time 2
maintenance and repair
life as rhythms (days, weeks, months)
describe the scale of time 3
homeostasis
life as balance (seconds, minutes, hours)
four inputs to health, disease, ageing
genetics, environment, lifestyle, healthcare behaviours
describe sleep and health
- complex process controlled by the brain
- coordinated with natural and fake light
- too little/too much, and rotating shiftwork= disease risk factors
how do we recognize the ageing process
if we can find things to measure objectively, then we can track the ageing process
we can refer to these as biomarkers or indicators of the biological state of the organism
where does height loss not occur
height loss with ageing is not occurring in long bones
vertebral compression
disk generation
compression fractures
biomarkers
often go by other terms depending on the discipline (blood values, anthropomorphic measurements)
most change during the lifespan
what is chronobiology
the study of timescales and cycles in biology
what is a biological rhythm
cycles in all zomes of biological rhythmicity
describe an ultradian biological rhythm
less than 24 hours (appetite)
describe a circadian biological rhythm
every 24 hours (height)
present in all physiological processes
controlled by gene expression, regulation of enzyme activities, neural function, hormone secretion
coordinates sleep, nutrient supply, and activity patterns with metabolic patterns required at different stages of the day
describe infradian rhythm
more than 24 hours (menstrual cycle)
disruption of the circadian rhythm can lead to what
disruption of circadian rhythms causes a wide spectrum of health problems and premature ageing
what is the suprachiasmatic nucleus
brian region which acts as central clock, which keeps time based on light signals from retina
what controlls cell metabolism
nearly every cell in the body has a subsidiary clock, which coordinates its metabolism with the rest of the body
describe how change in height is a simple form of circadian rhythm
- tallest when you wake up, shortest at night
- bones don’t shrink/expand (fluid-filled cushioning disks get compressed by gravity)
- sleep= rehydration and reformation of intervertebral disks
what is mineral turnover
bones are full of living cells, some of which are building the mineral structure, while others are breaking it. this is the mineral turnover
where do we get our calcium when we need it in our non-bone tissues
when we need calcium in our non-bone tissues, we obtain it from the dissolution of the minerals in bone.
where do we deposit excess calcium that enters the bloodstream
in bone, or excrete it in urine
what is the mineral structure of bone
the mineral structure of bone is composed of hydroxyapatite, which is an insoluble deposit of calcium and phosphate within an extracellular protein
what do you actually do when measuring bone density by DEXA
estimating the amount of the x-ray absorbing dense material, hydroxyapatite, that is packed in the extracellular space of the bone
describe direct intercellular communication through gap junctions
- pore size is very small (ions and small molecules only)
- gap junctions are tiny and plentiful (100+ between two cells)
describe direct communication through tunnelling nanotubules
- much larger than gap junctions
- pore size is larger( proteins, nucleic acids, small organelles)
describe indirect intercellular communication through chemical messengers
- chemical leaves the cell and go to target cell
- binding and conformational change is needed
describe indirect intercellular communication through mechanosignals
- as cells move, they tug on filamentous proteins of the EC space
- as cells or large molecules move by the cell, they can bend surface filament
describe autocrine/paracrine
- the signal does not travel through the bloodstream
- autocrine: signals self
- paracrine: signals to nearby cell
describe neurotransmitter
- 2 cells are very close: very few molecules escape the synaptic cleft (highly localized)
- fast
describe hormones
the signal travels through bloodstream
describe hydrophilic hormone messengers
crossing plasma membrane is a problem but it is soluble in ecf and blood plasma
examples of hydrophilic hormone messengers
insulin, epinephrine, growth factor
describe hydrophobic hormone messengers
diffuses across the plasma membrane, needs a carrier in blood plasma and ecf
examples of hydrophobic hormone messengers
estrogen, testosterone, cortosol, thyroid hormone
describe receptor specificity
- every cell has many types of receptors, all working at the same time
- every cell has the ability to up-regulate or down-regulate the reception of a cell-receptor type
properties of hydrophilic messengers
stored in secretory vesicles in secretory cells
excreted by exocytosis
dissolved in blood
binds to a receptor on pm
chemical classes of hydrophilic messengers
amino acids, amines, peptides
signal transduction mechanism of hydrophilic messengers
- open/close ion channels
- activate membrane-bound enzymes
- g-protein and secondary messenger systems
properties of hydrophobic messengers
does not get stored in secretory cells
secreted by diffusion
bound to a carrier protein in blood
receptors are locates in the cytosol or nucleus
chemical classes of hydrophobic messengers
steroids, thyroid hormones
signal transduction mechanism of hydrophobic messengers
alters transcription of mRNA after protein synthesis
signalling characteristics of the nervous system
secretory cell: neuron
target cell: neuron, muscle, glans
messenger: neurotransmitter
basis of specificity: receptors on the postsynaptic target cell
signalling characteristics of endocrine system L
secretory cell: endocrine cell
target cell: most cell types in the body
messenger: hormones
pathway for communication: bloodstream
basis of specificity: receptors target cells throughout the body
fluid secretion in the intestinal lumen
`
-maintaining normal fluid levels
CFTR: cystic fibrosis transmembrane conductance regulator
1) a chloride ion transporter protein
2) fatal diarrhea (cholera, listeria, salmonella)
3) thick lung mucus
4) large variations in amino acids at key control points
describe neurons
- around 200 configurations
- myelinated= faster
- built to signal specific target cells with a specific neurotransmitter
- sums the signals and when a threshold is reached, it fuels its own impulse down the axon (action potential impulse)
describe oligodendrocytes/ schwann cells
- 1 cell can have up to 30 myelin rolls
describe microglia
mobile macrophage-like immune cells
describe epidenmal cells
like the ventricles and produce cerebrospinal fluid
five functions of the astrocytic super-network theory
-coordinate the overall function of the BBB
provide nutrients to neurons
-coordinate function of the ventrical epithelium
-coordinate function at nodes of ranvier
-participate in tripartite synapse
-serve as “super hubs” for neural network vis syncytium formation and calcium wave signalling
describe the anatomical zones of the brain
symmetric
describe the functionality of the zones of the brain
asymmetric
what do pet scans do
light up the brain where there is the most activity
size of the zones is _____ to the # of activity of _____
size of the zones is proportional to the # of activity of peripheral nerves
information crosses the brain how
informational flow crisscrosses the longitudinal fissure
what is the behavioural modification network
network identified by neurons using the same neurotransmitter
describe the norepinephrine network
- modulates attention, sleep, arousal, learning, pain, mood
- fight or flight
- increased by a stimulus (coffee)
describe the serotonin network
- modulates locomotion, sleep, pain, emotion
- antidepressant drugs
what are antidepressants
selective serotonin uptake inhibitors
describe the dopamine network
- modulates motor control, reward centers
- low dopamine
what is Parkinson’s disease
low dopamine and dying neurons
acetylcholine network
modulates arousal, sleep, learning, memory, sensory information
low acetylcholine=
alzheimers
nootropics (smart drugs)
increase acetylcholine increased norepinephrine
increased learning, memory, attention, arousal
