BIOM1060 Lecture Notes - Lecture 43: Coronary Artery Disease, Diminished Responsibility, Vital Capacity
BIOM1060 30/05/18
AGEING (Part 2)
Cardiovascular system and ageing
- Hear muscle becomes stiffer and may increase in size
- Amount of blood chamber can hold decreases (heart wall thickens)
- Maximum heart rate decreases
- Restig heart rate ad cardiac output do’t chage
- Blood vessels become stiffer and less responsive to hormones that relax vessel walls
o Contributes to increasing systolic blood pressure
- Loss of nephrons = hypertension
- Loss of number of pacemaker cells: electrical pathways develop fibrous tissue and fat
deposits (lead to dysrhythmias)
- Shifts in circulation of blood to organs
- Heart murmurs common
- Baroreceptors less sensitive: cause orthostatic hypertension (falling blood pressure when
changing position causing dizziness and risk of falls)
- Increased risk of ischemic heart disease
Neoplasms and ageing
- Increased age = increased risk of cancer
o Cells more damaged, less capable of repair and immune decline
Respiratory system and ageing
- Lungs become stiffer
- Respiratory muscle strength and endurance diminishes
- Chest wall becomes rigid
- Vital capacity (air forcibly exhaled) decreases but total lung capacity relatively constant
o Residual volume increases (amount air remaining in lungs)
- Alveolar surface area decreases = reduced maximal oxygen uptake
- Exercise capacity declines (less reserve)
- Cilia (transport mucus out of lung) diminishes but mucus producing cells rise (clog airways)
o Inefficient in monitoring and controlling breathing
Urinary system - kidneys
- Renal function declines: both number and size of nephrons (filtering units) decrease
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Document Summary
Hear muscle becomes stiffer and may increase in size. Amount of blood chamber can hold decreases (heart wall thickens) Resti(cid:374)g heart rate a(cid:374)d cardiac output do(cid:374)"t cha(cid:374)ge. Blood vessels become stiffer and less responsive to hormones that relax vessel walls: contributes to increasing systolic blood pressure. Loss of number of pacemaker cells: electrical pathways develop fibrous tissue and fat deposits (lead to dysrhythmias) Shifts in circulation of blood to organs. Baroreceptors less sensitive: cause orthostatic hypertension (falling blood pressure when changing position causing dizziness and risk of falls) Increased age = increased risk of cancer: cells more damaged, less capable of repair and immune decline. Vital capacity (air forcibly exhaled) decreases but total lung capacity relatively constant: residual volume increases (amount air remaining in lungs) Alveolar surface area decreases = reduced maximal oxygen uptake. Cilia (transport mucus out of lung) diminishes but mucus producing cells rise (clog airways: inefficient in monitoring and controlling breathing.
