Explanation

by a route outside the vascular system, requiring dissolution and absorption across biologic barriers before reaching systemic circulation; oral drugs must cross the GI tract wall, transdermal patches must penetrate the skin, and effect is delayed because absorption and subsequent distribution take time.

Check My Knowledge

1: Which term describes a substance being located outside blood vessels?

Options:
    A: Intravenously
    B: Extravascularly
    C: Subcutaneously
    D: Intravascularly

Answer: B. Extravascularly
2: A clinician documents that a medication has spread outside the vascular space. Which descriptor matches that location?

Options:
    A: Intravascularly
    B: Intravenously
    C: Subcutaneously
    D: Extravascularly

Answer: D. Extravascularly
3: Which option is the best match for the adverb meaning outside the vessels?

Options:
    A: Intravenously
    B: Intravascularly
    C: Subcutaneously
    D: Extravascularly

Answer: D. Extravascularly

Bioavailability is the fraction of a medication dose that reaches systemic circulation; it is 1 (100%) for intravascular administration and less than 1 for other routes when some drug fails to enter circulation.

Extravascularly means a drug is given outside the vascular system, so it must be absorbed before reaching systemic circulation.

Leukemias are blood cancers; acute leukemias in children can mimic juvenile systemic inflammatory arthritis with severe joint pain and fever, adult chronic and acute myeloid leukemia rarely infiltrates the synovium, and hairy cell leukemia can cause episodic inflammatory oligoarthritis and tenosynovitis that mimic acute gout flares and may respond to glucocorticoids, abating with leukemia remission.

Explanation

Genetics influences many traits through genes, which contain exons, introns, and regulatory regions; alleles are the nucleic acid sequence at a gene locus, homozygous means two identical alleles, heterozygous means two different alleles, and phenotype is the outward expression of the genotype. Genetic mutations can cause disorders such as osteoporosis, osteogenesis imperfecta, and juvenile idiopathic osteoporosis, and family history—especially a parental hip fracture—is a strong risk factor for osteoporosis and fracture. In obesity, genetics contributes substantially to both obesity and fat distribution, with an estimated 40% to 70% of BMI and body-fat variance attributable to genetic factors; rare single-gene mutations cause extreme obesity in about 5% of cases, but most obesity is polygenic and also shaped by environmental factors.

environment