Answer:
Abstract
Down syndrome (DS) is associated with aberrations in genetic, morphological, biochemical and physiological characteristics. A number of genes located on human chromosome 21 (HSA21) encode proteins which are thought to be involved in numerous metabolic pathways, e.g., phosphofructokinase, cystathionine β-synthase etc. Perturbations of the metabolic pathways may lead to altered drug metabolism in DS individuals. We present a review of metabolic aberrations linked to HSA21 genes in DS. We particularly focus on drug disposition, efficacy, sensitivity and toxicity of anti-leukaemic agents including methotrexate, glucocorticoids, anthracyclines and cytarabine in DS leukaemia. The different outcomes of therapy due to differential drug response, varied drug toxicity and treatment related mortality in DS leukaemia is a subject of much research and speculation. Altered drug response in DS individuals may stem from differences in pharmacokinetics, pharmacodynamics and pharmacogenetics. Further large-cohort studies in different age groups dissecting metabolic and molecular pathways involved in drug response may increase our understanding in this regard and stipulate pharmacotherapies in DS.
Answer:A selectively permeable cell membrane is one that allows certain molecules or ions to pass through it with active or passive transport.
Explanation:
Answer:
The correct order is
1. Weathering
2. Erosion and Transportation
3. Deposition
4. Sedimentation
Explanation:
The process involved in the formation of sedimentary rocks are –
a) Weathering – In this a preexisting rock is weathered into fine particles or pieces
b) Erosion & Transportation – the weathered fine particles are further disintegrated into fine powder so that they can be easily carried away by the force of wind, water , glaciers etc.
c) Deposition – The transported soil is deposited layer by layer with oldest layer at the bottom ,
d) Sedimentation – It is the compaction of loosely deposited soil to form silica and calcite gel.