114 terms

health psych_ch2

dynamic physiological response on the part to maintain a stable internal state in spite of the demands of the envn't
-require constant monitoring of ur internal states and a response to the changes
-psychological factors also affect homeostasis
body communicates with itself in a number of ways, most commonly via electrical impulses conducted through
nerve cells OR neurons
afferent neurons vs. efferent neurons
former: nerve cells that conduct impulses from a sense organ TO CNS, from lower to higher levels in the spinal cord and brain
latter: nerve cells that take impulses AWAY from the brain
biochemistry of synaptic transmission focuses on
neurochemicals or neurotransmitters that are secreted or received by neurons, allowing for communication between cells
-affected by our psychological state and in reciprocal fashion, affects our psychological experience
people with multiple sclerosis (neural transmission)
experience double vision, numbness, extreme fatigue, loss of bowel or bladder control, speech difficulties, and poor motor control
people with myasthenia gravis
blurred vision, dropping eyelids, difficulty eating bc of problems with chewing and swallowoing
central nervous system
consist of cells that make up to brain and spinal cord
peripheral nervous system
collection of neural pathways that take information to and from the CNS to the rest of the body
-made up of somatic nervous system and autonomic nervous system
-autonomic nervous system (divided into sympathetic and parasympathetic nervous system)
main components of CNS
neurons and gilial cells
gilial cels (CNS)
make up about about 90% of CNS cells
1)support system for neurons
2) providing nourishment
3) helping neurons maintain proper physical orientation to each other
blood-brain barrier
acts as a sentinel for materials that enter the brain vis. bloodstream
nervous system disease
meningitis (infection of fluid that protects the brain and spinal cord)
symptoms of meningitis in ppl over age of 2: high fever, headache, and stiff neck
difficult to attack among newborns and infants
babies under three months given "fever without a source" ->routinely tested for meningitis and infections of bloodstream and urine
bacterial vs. viral meningitis
former: result in brain damage, hearing loss, learning disabilities or death
latter: resolves itself without specific treatment
brain stem
base of the brain
-connects the brain to the spinal cord
-controls some very basic functions eg)breathing and sleep-wake cycles
-above the brain stem
-little brain
-control of balance and coordination of voluntary movement
below the centre of the brain
about size of a lima bean
-central control mechanism for homeostasis*
eg)responsible for maintaining a steady body temp. and also monitors hunger and thirst
combination of hypothalamus and pituitary gland
form a sign communication point between neural and hormonal systems
-this helps hypothalamus control sexual behaviour and reproduction
above hypothalamus
-manages synaptic input to the brain, sending impulses to the appropriate part of the brain
cerebral cortex
divided into hemispheres, separated into four lobes
1) occipital lobe
2)temporal lobe
3) parietal lobe
4) frontal lobe
occipital lobe
contain visual cortex
responsible for interpretation of impulses that come in through the light-sensitive receptors (rods and cones) in the eyes
temporal lobes
vicinity of the ears
responsible for interpreting sound
pareital lobes
responsible for processing sensory information eg)touch and temp regulation
frontal lobe
voluntary movement, language, thought processing, emotion
motor cortex
controlling voluntary movement
lower part of this: facial movement
upper: limb and trunk movement
sensory cortex
sensory activities in specific parts of the body as well as sensations from the skin, muscles, and joints
contralateral control
each hemisphere controlling the opposite side of the body
broca's area
production of speech
wernicke's area
junction of occipital, parietal, and temporal lobes
controls the understanding and interpretation of language
reasons for brain damage
1)blows to head
2)oxygen deprivation: result of cerebrovascular accidents
3)growth of tumours
form of cardiovascular disease (CVD)
1) ischemic stroke
caused by blockage
2) hemorrhagic stroke
caused by blood vessel rupture
*speech therapy and other physical therapy useful in helping stroke victims
-may cause a personality change
sensory afferents
carry sensory information TO brain VIA spinal ord
-info about temperature, pressure, and pain
-body position and balance
-also cary information regarding vision, hearing, taste, and smell DIRECTLY to the brain WITHOUT engaging spinal cord
somatic nervous system
voluntary activity and control skeletal muscles
autonomic nervous system
involuntary activity
control cardiac muscle of the hart, smooth muscle of the internal organs, and most glands
*very important for maintenance of homeostasis
this maintenance is achieved via sympathetic and parasympathetic systems
*work together in an ANTAGONISTIC manner (while one works to increase an organ's activity, the other will work to decrease it
eg) sympathetic stimulation incr. heart rate, parasympathetic decr.
sympathetic disrupts digestive tract
parasympathetic aids digestion
feeling of butterflies in the stomach --> sympathetic stimulation
sympathetic nervous system
fight or flight response when triggered by hypothalamus
-required to mobilize the body for stress or challenge
parasympathetic nervous system
re-establishes homeostasis in the system and promote reconstructive process following a stressful experience
-most active when we are at rest
endocrine system
consists of a collection of glands found throughtout the body
glads share one IMPORTANT trait: secrete hormones
endocrine system vs. nervous system
former: features control of a longer duration
helps body cope with stressful situations
control developmental phenomena eg)growth and metabolism
latter: rapid control
main control centres for endocrine system
pituitary gland
produces hormones that stimulate other glands rather than organs
-produces 8 hormones
tropic hormones
hormones produced to stimulate other glands
eg) ACTH: produced by anterior lobe of pituitary gland
/stimulates the adrenal gland to produce cortisol
two important glads in endocrine system
1)thyroid gland
regulate growth and immune function
2)adrenal gland
produce cortisol which provides energy by helping the boy convert stored proteins and fats into glucose
common disease that results from a malfunction in the endocrine system
(caused by too little secretion (hyposecretion) of insulin/ one of the symptoms: extreme fatigue
hormone produced by pancreas
adis in body's ability to convert blood sugar to energy
lowers blood sugar levels while glucagons raise them
immune system
designed to monitor invasion of micro-organisms in the body and prevent spread and growth by eliminating them
-guard against infection and growth of cells associated with disease
1) antigens
micro-organisms that are foreign to our physiology
2) pathogens
antigens that have potential to create disease
immune system's first line of defence
skin and mucus
(where most* antigens are stopped)
when immune system detects an antigen, acts in one or more ways to eliminate it.
This action can be either
specific or non-specific
1) specific immunity: protection against a particular antigen
**acquired immunity: acquired sometime after birth/
result of prior exposure to the antigen eg)either by contracted the disease or inoculation
*specific immune function is the consequence of acquired immunity
2)non-specific immunity: relies on a system we are born with. general* protection against antigens rather than against one specific antigen
three aspects to its effective functioning
immune system memory
ability of certain immune system cells to adapt to an antigen and ''remember'' the antigen when it encounters it again and work to eliminate it
eg)chicken pox
more susceptible to certain disease when travel to foreign destinations
Cells of the Immune System
1)B lymphocyte cells
2)Memory B-cells
3)Helper T-cells
4)Suppressor T-cells
5)Natural killer cells
B lymphocytes
produce antibodies that attack antigens
produce antigen-specific for specific, acquired immunity
memory B-cells
particular kind of B lymphocyte
-develops a memory for a specific antigen after being exposed to it and acts only on that specific antigen by producing antibodies
production of antibodies by memory B cells when exposed to a specific previously encountered and remembered antigen
Helper T-cells
T lymphocytes
produce substances called interleukins that speed up division of B lymphocyte cells
a measure of how well our immune system is working
interleukin production
supressor T-cells
''off-switch'' so antibodies aren't produced unnecessarily after antigen has been destroyed
B-cells and T-cells
work together to maintain immunity
B-cells: take 5 or more days to generate specific antibodies
occur more quickly when re-exposed to the antigen
*reason why we receive inoculations before travelling work
respond to ONLY remembered* antigen
react only to antigens, 'non-self'
does not react to body's own cells
natural killer (NK) cells
specific job of seeking and destryong cells that are infected, cancerous, or altered in some other way
rapid and efficient production of lymphocytes
essental to immunocompetence
-effective functioning of immune system
autoimmune diseases
occur when immune system works against the body's own cells
one of the best known type: arthritis
circulatory system consists of
heart, vessels, and blood
pulmonary circulation
a closed loop between the heart and lungs in which blood is transferred from heart to lungs for the replenishment of oxygen
systemic circulation
a loop that links the heart to other body systems and returns oxygen-depleted blood
heart has a total of 4 chambers
upper two: atria
receive blood returning to the heart and transfer it to the ventricles (pump the blood from the heart to either lungs -> pulmonary circulation OR other aspects of the body (systemic circulation)
lower two: ventricles
right-side atrium received blood from systemic circulation
low in Oxygen and high in carbon dioxide
this blood flows to right ventricle, pumped through pulmonary system via pulmonary artery
in the lungs
blood loses excess CO2, and picks up O2
-returns to the left atrium via pulmonary veins.
oxygen rich blood flows to left ventricle (pumped out via systemic circulation)
main artery carrying oxygen rich blood away from the heart
reason why left side of heart generate more pressure than the right side
left side of heart pumps blood to the entire body
*left size of the heart muscle is thicker and stronger
capacity of a cardiac muscle cell to fire by itself
-pulsing of heart is regulated by autorhythmic cells, which in turn stimulate contractile cells
contractile cells
require stimulation from other cells in order to fire
-bring about contraction that constitutes the work of pumping
pulsing of heart is regulated by
autorhythmic cells (which in turn stimulate contractile cells)
electrical activity of the heart is important to health psychologists because
arrhythmia (irregular beating of the heart) can be caused by malfunction of autorhythmic* cells that are responsible for ''keeping time''
arrhythmia can be brought on by many factors
lack of sleep
disease process
*symptoms of arrhythmia can be anxiety-inducing
contraction of heart during pumping
-heart is emptied
relaxation of heart during pumping
-heart is filled
blood pressure
measured in terms of systolic and diastolic activity and reported as two numbers -> systolic pressure over diastolic pressure
*systolic pressure is higher of two numbers
*measured via sphygmomanometer
*circulatory system uses a complex process to monitor and automatically adjust this/a function of cardiac output
*important health consideration because serious complications can rise from hypertension
abnormally high blood pressure
in excess of 140/90 mm Hg
-heart must work harder in the event of increased peripheral resistance from fatty deposits, which reduce artery diameter, and this can result in congestive heart failure or heart attack
*particularly dangerous because it is asymptomatic
abnormally low blood pressure
below 100/60 mm Hg
conditions that are NOT accompanied by palpable symtoms or sensations
two kinds of respiration
getting oxygen in and CO2 outside of body as waste product
cells using O2 and producing CO2
taking in of O2 from external env't
eg)breathing, exchange of O2 and CO2 between the lungs and the blood, transportation of O2 and CO2 by the blood, and exchange of O2 and CO2 between blood and tissue
divided into 5 lobes, with left lung having 2 lobes and right lung having 3
chronic obstructive pulmonary disease (COPD)
primary symptom: shortness of breath, tends to worsen with time
Two most common forms of this:
1)chronic bronchitis
inflammation that irritates the airways and blocks them by producing extra mucus
results from damaged or destroyed lung issue, causing large air pockets to be trapped in the lungs, making breathing difficult
MAIN CAUSE OF EMPHYSEMA: cigarette smoking
lung disease most associated with cigarette smoking
lung cancer
29% men, 25% women
common respiratory condition
(greater risk for developing asthma for those who are predisposed to particular allergies and then exposed to those allergies, exposed to evn't toxins)
i)lobar pneumonia
infection of entire lobe of the lung (inflammation of alveoli -> infection causes inflammation spread to other organs
ii)bronchial pneumonia
restricted to bronchi and often occurs as complication of other illness such as cold or flu
two main causes of asthma
1)inflammation of airways
2)narrowing of airways caused by muscle tightening or spasm
work on bacterial infections but not on viral one
NO therapeutic value for viral infections
digestive system
consists of digestive tract and accessory digestive organs
-relies on muscle activity
muscles are skeletal and movements are voluntary
digestive tract
made up of mouth, throat, esophagus, stomach, small intestine, large intestine, and anus
4 basic processes of digestive system
motility (one of basic processes of digestive system)
process of moving food through the system and mixing it with digestive juices
-emotions affect this eg)fear and sadness DECREASE ___ and thus disrupt digestive process
small intestine
major site of absorption
-contractions of smooth muscles in this area occur such that propulsive movements are slow
stomach (motility)
an important role in managing difference between rapid flow of food through esophagus and much slower flow through small intestine
-> food sent quickly via esophagus and release it into small intestine at a rate that allows intestine to perform task of absorption
-stomach begins mixing it with hydrochloric acid and enzymes to begin digestive process
-emesis*: emptying of stomach's contents
-common conditions
ii)peptic ulcer
medulla* contains vomit centre to initiate the process
-may be caused by stimulation of back of throat; irritation of stomach or duodenum; rotation or acceleration of head, producing dizziness; ingestion of chemical agents;psychological factors
-also caused by elevated intracranial pressure after a head injury
medicines designed to reduce nausea and impulse to vomit
peptic ulcer
walls of stomach and other parts of digestive trat are protected from pepsin by mucous layers.
-but this layer breaks down in some cases, because of intrusion of bacteria called H.pylori (able to exist even in highly acidic world of stomach)
-H.pylori secrete toxins that bring about inflammation that weakens this mucosal protection
-pepsin begins to erode the wall of stomach, resulting in bleeding or escape of gastric contents
-psychological factors such as stress can contribute to the dev'pt of ulcers by stimulating greater gastric secretion and more pepsin
along digestive tract, glands secrete fluids that aid in digestion
-these glands receie hormonal and neural stimulation, drawing materials needed to produce these juices from the blood
enzymes produced within digestive system perform biochemical breakdown of carbohydrates, proteins, and fats into molecular-size forms that allow for absorption
-in the process of _____, carbohydrates are converted into simple sugars -> glucose, fructose, and galactose
foods high in carbohydrates should be consumed BEFORE athletic competition or physical exertion
two reasons for this
1) sugars derived from carbohydrates do provide a source of energy
2) carbohydrates move through digestive system more quickly than do fats and proteins
-proteins are broken down into amino acids that constitue proteins
most fats are broken down from
triglyceride to monoglyceride form
nutrients move from digestive tract to blood stream and lymphatic system
-occurs primarily in small intestine
-motility, secretion, and digestion SUPPORT _____, by working to move the lumen along digestive tract, break it down, allow for clearing of tract in small intestine so it can continue its work unimpeded
-problems with absorption
1)lactose intolerance
-buildup of lactose in small intestine (cause accumulation of water)
-bacteria in large intestine can use lactose as energy source -> move in and produce gases as they attack lactose -> result: painful cramping and diarrhea
inability to efficiently absorb nutrients from digestive system (may be caused by gluten enteropathy)
-symptoms of gluten enteropathy: diarrhea and weight loss
-treated by modification of diet to eliminate gluten
kidney functions
-help us maintain our internal water balance, regardless of how much of it we drink or how much of it we lose via perspiration, vomiting, diarrhea, or bleeding
-control electrolytes (substances dissolved in water capable of conducting electricity
eg)salt (NaCl)
-help maintain homeostasis by eliminating excess amounts of water and electrolytes
-CANNOT produce, rather RETAIN
-eliminate metabolic toxic waste materials from the body
-important role in blood pressure regulation by controlling levels of water and salt in blood
-consist of millions of tiny functional units called nephrons
those who study kidney diseases
-workings of arteries and veins that flow into and out of the kidneys --> renal arteries and renal veins -> renal system
destructions of nephrons
gradually shut down functioning of one kidney or both
kidney dialysis
uses external devices to do work of kidneys
genito-urinary (GU)
reproductive system is located in close proximity to the urinary system
-refer to this group when talking about prostate or ovarian cancer
primary organs responsible for reproduction
gonads in males: testes
females: ovaries
-produce sex hormones
testosterone for males
estrogen and progesterone for females
testosterone and estrogen: regulate secondary sexual characteristics
primary functions of male reproductive system
production of sperm and transport that to female
female reproductive system
responsible for much more biological activity
one of methods used to assess progression of labour
cervical dilation
breast cancer
because of it that cancer rates are higher for women between ages of 30 and 39
cardiovascular disease
Myocardial infarction (heart attack)
Cerebrovascular accident (stroke)
-the leading cause of mortality worldwide
In Canada:
-Kills 80 000 people each year
-Accounts for 34% of deaths in men and 33% in women
-Costs the health care system over $18 billion each year
-These numbers are expected to increase
risks factors of cardiovascular disease
High blood pressure
High LDLS, from saturated fats /HIGH HDL: GOOD cholesterol
Triglyceride: vegetable oil, animal fats
Diabetes, obesity, smoking, elasticity,
Physical activity -> direct effect of elasticity on the arteries/ keep blood pressure down/ direct preventive behaivour of heart disease
Excessive alcohol consumption
Major cause of heart disease
-Caused by deposit of cholesterol or other substances on the wall of arteries/ form plugs/ narrow arteries , make hard for blood to come through, incr. blood pressure, contribute to arteries becoming LESS elastic
When arteries wall become damaged, inflammation -> walls of arteries cause immune system to repair/ get rid of it/ too much waste is getting accumulated -> constant of infammation/ heart has to pump stronger