article Flashcards
what is atherosclerosis
is a progressive disease in which plaques (consisting of deposits of cholesterol and other lipids) build up in the walls of arteries
what does a tumor mean
a group of abnormal cells that form lumps or growths
state two factors other than old age,that increase the risk of cvd
- obesity
- high blood pressure
- high blood cholesterol
- being male
- lack of exercise
- smoking
- genetics
- high alcohol consumption
- high salt diet
- high saturated fat intake
- stress
- diabetes
state levels of organisation
cell,tissue,organ,organ system,organism
why is coronary heart disease ,more common with old age?
- decrease in elasticity of the artery wall
- thus decrease in the ability to respond to changes in pressure
- therefore increase in the resistance to the pumping action of the heart thereby increases the work needed to drive the blood to the various organs of the body
- accumulation of cholesterol,thus increased risk of atherosclerosis
explain how the heart rate of a person is controlled as the level of exercise increases during this test (treadmill)
- increase in respiration rate in muscle cells
- more co2 in blood (reduced blood ph)
- more lactic acid in blood
- chemoreceptors in medulla stimulated
- ref to cardiovascular control centre in medulla
- ref to autonomic nervous system. sympathetic nerve
- more impulses from medulla to SAN
- more noradrenaline/norepinephrine released onto SAN
- SAN (excitation) rate increased
- causing an icreased heart rate
- comment on other mechanism eg. presence of adrenaline, stretch receptor role
why is cancer more common with old age?
- accumulation of mutations over years
- accumulations of mutations due to exposure of mutagens over the year
- lose expression of genes (deactivation) important in the cell cycle regulation (due to epigenetic changes -environment)
state two categories of genes that when mutated they lead to cancer
- oncogenes
- tumour suppressor genes
state the name of a tumour suppressor gene , involved in apoptosis, that is commonly deleted in cancer cells
p53
what happens to the cell cycle if both copies of the tumour suppressor gene are mutated ?
- loss of control
- the cell continues through the cycle
name one envrionmental factor , other than uv light, that can cause a cell to become cancerous
carcinogens/cigarettes/tobacco - ionising radiation/ xrays
suggest how the cell cycle will be affected in cells that have become cancerous
- shorter growth or G phase/ shorter interphase
- shorter/faster cycle
- cells divide uncontrollably
- cells do not become specialised
what is diabetes type 2
-the body cannot control /maintain glucose levels
-blood glucose levels are higher than normal
-due to insulin resistance
/ insulin does not work properly
difference between lifespan and life expectancy
- life span is the maximum time a person can live
- whereas life expectancy is the average time a person will live, based on factors like gender and birth year
- life expectancy is an average.it can be lowered due to infant mortality
in 1700 the life expectancy was 30, now it is 77. what is the percantage increase?
157%
why was life expectancy increased?what has changed?
- decline in infants deaths
- better medications
- better health system
- clean water
- warmer housing
- end of child labour
- better management of infectious diseases
what does inherent mean?
it is intrinsic
give one difference between an organ and a tissue
- organ has many functions tissue has one/fewer
- organ has several cell types/tissues , tissue has one