normal
(Science: microscopy) An imaginary line forming a right angle with the tangent to a curved surface at a particular point. It is used as a basis for determining angles of incidence, reflection, and refraction.
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Genetic Mutations
This tutorial looks at the mutation at the gene level and the harm it may bring. Learn about single nucleotide polymorphisms, temperature-sensitive mutations, indels, trinucleotide repeat expansions, and gene duplication...
Chromosome Mutations
Mutations can also influence the phenotype of an organism. This tutorial looks at the effects of chromosomal mutations, such as nondisjunction, deletion, and duplication. ..
Regulation of Organic Metabolism, Growth and Energy Balance
The human body is capable of regulating growth and energy balance through various feedback mechanisms. Get to know the events of absorptive and post-absorptive states. This tutorial also describes the endocrine and neural control of compounds such as insulin and glucagon. It also deals with the regulation of growth, heat loss, and heat gain. ..
Physiological Homeostasis
Homeostasis is essential to maintain conditions within the tolerable limits. Otherwise, the body will fail to function properly. The body does this through feedback control mechanisms, e.g. blood sugar level regulation and temperature regulation. Read this tutorial to know more about the principles of negative feedback control employed by the body to sustain homeostasis...
Non-Mendelian Inheritance
In this tutorial, find out more about certain types of inheritance that does not follow the Mendelian inheritance patterns. Examples are incomplete dominance and complete dominance...
Respiration
The human respiratory system is an efficient system of inspiring and expiring respiratory gases. This tutorial provides details of the different parts and functions of the respiratory system...