<span>The kidney is made up of filtering units called nephrons. The number and size of nephrons slowly decreases with age, the kidneys start to lose its function, meaning, the waste and extra fluid are not filtered out of the body as effectively in older people. The kidneys become smaller with age, Blood flow to the kidneys is also reduced. This also impairs the filtering process.
Another function of the kidneys is to balance the amount of salt and acid in the body. This function also decreases with age, the production and efficiency of hormones that tell the body it is becoming dehydrated declines with age. This poses a risk for dehydration.
Bladder tissue becomes much less stretchable as one gets older. This decreases the amount of urine the bladder can hold. The muscles of the bladder also become weaker, making the bladder unable to squeeze hard enough to get rid of all the urine it contains, so more urine is left in the bladder after a person urinates. These two changes may cause an older person to have to urinate more often.
The sensation of needing to urinate is often delayed in older people. When an older person finally feels the need to urinate, the need may be sudden.</span>
Answer:
The mutated cystic fibrosis transmembrane conductance regulator (CFTR) blocks the entry of <em>Salmonella typhi</em> into the epithelial cells.
Explanation:
Cystic Fibrosis Transmembrane Conductance Regulator (CFTR):
CFTR is a membrane protein and a chloride channel that regulates the influx and eflux of chloride ions. Cystic fibrosis is a disorder that occurs due to the presence of two recessive alleles in an individual.
Background:
In terms of immunology and defense against infectious disease, CFTR acts as a receptor for the bacteria, <em>Pseudomonas aeruginosa, </em>which is the leading cause of infections in CF patients<em>. P. aeruginosa </em>binds to normal CFTR receptors and is effectively removed from the body. But a mutated CFTR cannot bind the bacteria effectively, leading to life long <em>P.aeruginosa </em>infections.
Mutated CFTR Immune to <em>Salmonella typhi:</em>
<u><em>Salmonella typhi </em></u><u>enters the body by binding to the CFTR receptor</u><u>.</u> As a natural defense mechanism, <em>S. typhi</em> binds to CFTR on the epithelial cells of the GIT, which, in turn, engulf the bacteria and then slough off from the lining. But, a severe attack leaves the lining open for attack as the epithelial layer sloughs off.
A mutated or missing CFTR receptor is unable to effectively bind to <em>S. typhi</em>; leaving the carrier of the mutated CF allele immune to typhoid infections.
Answer:
by diluting the DCIP dye stock solution 1000 times. It can be done by diluting 0.1 ml of the DCIP dye stock solution with 99.9 ml of distilled water
Explanation:
1 millimolar (mM) = 0.001 M
1.0 × 10⁻⁴ Molar (M) = 0.0001 M = 0.1 mM
Stock solution = 100 mM = 0.1 M
100 mM DCIP dye solution diluited 1000 times >> 0.1 mM = 1 x 10⁻⁴ M
A disease (also known as a blood cancer) affecting the blood, bone marrow, or lymph nodes in which normal blood production and function is interrupted by the uncontrolled growth of an abnormal type of blood cell.