Againg

Is the permanent cell growth arrest normal and physiological processes but also cells stop dividing

The number of times a normal human cell population will divide before cell division stops

skin changes occur in the dermis Fibroblasts decrease Collagen fibres stiffen, separate and become disorganised Elastic fibres lose elasticity

1.Environmental, biological and psychological influences 2.Variable experience, interpreted differently by each person 3.Accumulation of damage within cells 4.Cellular metabolism becomes less efficient with age 5.Leads to loss of function 6.Results in cell death

decrease and macrophages are less efficient so the skin’s immune response is decreased

Sebaceous glands shrink, producing less oil Skin becomes thinner and more prone to injury Skin heals badly Wounds can become chronic

A decrease in functioning causes grey hair and uneven skin tone an increase in size causes age, or liver spots

Osteoporosis: 80% sufferers female More Calcium broken down than replaced Loss of bone density Increased bone weakness Risk of fractures

exaggerated, forward rounding of the back.

Degenerative joint disease Articular cartilage erodes Friction at joints Pain, swelling and stiffness

Atrophy due to a decrease in adipose tissue Decrease in musculoskeletal fibres Reflexes and flexibility decrease

Bone marrow produces less WBCs T cells less responsive so fewer respond to infection or invasion by pathogen B cells less responsive so antibody levels take longer to rise in response to infection Increased susceptibility to viral and bacterial infections Difficulties identifying self and non-self leading to risk of autoimmune diseases. Macrophages work more slowly

Produce less cortisol Fluctuating levels affect circadian rhythms Lack of good quality sleep increases stress and depression

Produce less aldosterone Less vasoconstriction Less sodium reabsorption in the nephron Increased urinary frequency

Decreased production of human growth hormone Increased muscle atrophy

Releases insulin more slowly Insulin Resistance Sugar levels increase faster with food and return to normal more slowly

Parathyroid levels increase with age.

In ageing, parathyroid levels are constantly elevated creating a continuum of bone degradation.the osteoblasts become less active. In contrast, the osteoclasts become more active

kidney function is generally reduced, resulting in less calcium reabsorption so that calcium levels remain low. This triggers the release of more parathyroid hormones exacerbating the problem

poor diet limits the presence of calcium in the gut. Sedentary indoor lifestyles limit exposure to the sun.

Brain mass declines Synaptic contacts deteriorate and fewer neurotransmitters are produced. Information is processed more poorly. Decreased conductive velocity causes slower voluntary motor movements and reflexes

is part of the basal ganglia it produces dopamine in ageing due to the degeneration of these neurones less dopamine is produced

Abnormal accumulations of proteins (Tau) collect in the neuron.In Alzheimer’s tau separates from the microtubule and sticks to other tau molecules. This causes a neurofibrillary tangle which interferes with the synapse.

As we age, our chest wall and lungs lose their natural elastic recoil, leading to decreased tidal volume. Additionally, there is a gradual increase in rib calcification, which causes rigidity in the chest wall. Loss of muscle strength in the chest wall and diaphragm also inhibits breathing efficacy. Lastly, the gradual drying out of intervertebral discs causes kyphosis.