Againg Flashcards
What is senescence
Is the permanent cell growth arrest normal and physiological processes but also cells stop dividing
What is the hayflick limit
The number of times a normal human cell population will divide before cell division stops
What occurs to the integumentary system during ageing
skin changes occur in the dermis
Fibroblasts decrease
Collagen fibres stiffen, separate and become disorganised
Elastic fibres lose elasticity
what are biological ageing
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
what happens to Langerhans cell during ageing
decrease and macrophages are less efficient so the skin’s immune response is decreased
What happens to Integumentary system – maintenance and repair
Sebaceous glands shrink, producing less oil
Skin becomes thinner and more prone to injury
Skin heals badly
Wounds can become chronic
What happens to the melanocytes
A decrease in functioning causes grey hair and uneven skin tone an increase in size causes age, or liver spots
What happens to the skeletal system
Osteoporosis:
80% sufferers female
More Calcium broken down than replaced
Loss of bone density
Increased bone weakness
Risk of fractures
What is kyphosis
exaggerated, forward rounding of the back.
What is osteoarthritis
Degenerative joint disease
Articular cartilage erodes
Friction at joints
Pain, swelling and stiffness
what is sarcopenia
Atrophy due to a decrease in adipose tissue
Decrease in musculoskeletal fibres
Reflexes and flexibility decrease
what happens to the lymphatic system
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
what happens to the adrenal glands
Produce less cortisol
Fluctuating levels affect circadian rhythms
Lack of good quality sleep increases stress and depression
Adrenal Glands – Aldosterone reduction in ageing.
Produce less aldosterone
Less vasoconstriction
Less sodium reabsorption in the nephron
Increased urinary frequency
what happens to the anterior pituitary gland
Decreased production of human growth hormone
Increased muscle atrophy
what happens to the pancreas
Releases insulin more slowly
Insulin Resistance
Sugar levels increase faster with food and return to normal more slowly
what happens to the parathyroid glands
Parathyroid levels increase with age.
what happens to the parathyroid glands and bones
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
what happens to the parathyroid glands and kidneys
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
what happens to the parathyroid glands and intestine
poor diet limits the presence of calcium in the gut.
Sedentary indoor lifestyles limit exposure to the sun.
what happens to the nervous system
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
what is the substantia nigra
is part of the basal ganglia it produces dopamine in ageing due to the degeneration of these neurones less dopamine is produced
what happens to the Neurofibrillary Tangles and Plaques
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.
What happens to the respiartory system
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.
