Tag: disorders of musculoskeletal system

Muscular dystrophy is a genetic disease, osteoporosis is the decrease in bone mass, which leads to higher chances of fractures with advancing age.

Osteoporosis causes bones to become weak and brittle — so brittle that a fall or even mild stresses such as bending over or coughing can cause a fracture. Osteoporosis-related fractures most commonly occur in the hip, wrist or spine. So the correct option is 'decreased level of progesterone'.

Paraplegia is an impairment in motor or sensory function of the lower extremities. It is usually the result of spinal cord injury.

Osteoporosis is a progressive bone disease characterized by a decrease in bone mass and density which can lead to an increased risk of fracture. In osteoporosis, the bone mineral density is reduced. Low levels of vitamin D is associated with osteoporosis.
Therefore, the correct answer is option A.

Myasthenia gravis is an autoimmune disease that destroys the skeletal muscles responsible for actions such as swallowing, breathing, etc. It is caused due to the inability of muscles to respond to the nerve impulse due to the destruction of the receptors of acetylcholine on them. The acetylcholine is secreted from the neurons at the neuromuscular junction which is not perceived by the muscles as their receptors have been destroyed by the antibodies.

Osteoporosis is an age related disorder of skeletal system caused due to weakening of bones by decreased Ca++ and oestrogen levels. Osetrogen helps in decreasing the resorption of bone by decreasing osteoclastic activity. As the oestrogen levels decrease the osteoclastic activity increases and more ca++ is withdrawn into blood from bone resulting in osteoporosis. 

Osteoporosis is bone disorder in which the Ca++ is decreased resulting in decreased bone mass. This may lead to fractures.

Lathyrus sativus (grass pea) causes the neurological disorder known as lathyrism or neurolathyrism. It has high concentration of neurotoxin β-oxalyl-L-α,β-diaminopropionic acid which causes paralysis. It is a poison of mitochondria which causes cell death.

An autoimmune disorder is a condition where body's own immune system attacks and destroys own tissues by mistake. Myasthenia gravis is an autoimmune disorder in which body produces antibodies agaist the neurotransmitter acetylcholine nicotinic in skeletal muscles. It is characterized by the muscle weakness. 

Tetany is rapid spasms in muscles due to low calcium ions in the body fluid or blood. Hyposecretion of parathormone lowers concentration of calcium ions in the blood due to excretion of calcium in urine, this increases the excitability of nerves and muscles, causing cramp and convulsions, this disorder is known as tetany.