Sickle cell anaemia has not been eliminated from the African population because :
- it is controlled by recessive genes
- it is not a fatal disease
- it provides immunity against malaria
- it is controlled by dominant genes
The Correct Option is C
Solution and Explanation
Sickle cell anemia has not been eliminated from the African population because it provides immunity against malaria. Heterozygous carriers of the sickle cell gene have some resistance to malaria, which is common in certain regions of Africa where the disease is prevalent.
Therefore, the correct option is (C): it provides immunity against malaria
Top Questions on Principles of Inheritance and Variation
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The sequence of nitrogenous bases in a segment of a coding strand of DNA is
5' – AATGCTAGGCAC – 3'. Choose the option that shows the correct sequence of nitrogenous bases in the mRNA transcribed by the DNA.- CBSE CLASS XII - 2025
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OR,
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Questions Asked in NEET exam
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A full wave rectifier circuit with diodes (\(D_1\)) and (\(D_2\)) is shown in the figure. If input supply voltage \(V_{in} = 220 \sin(100 \pi t)\) volt, then at \(t = 15\) msec:
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Concepts Used:
Human Endocrine System
The human endocrine system is a messenger system that balances or controls distant target organs through feedback loops of hormones released by the internal glands of an organism right into the circulatory system. The hypothalamus is the neural control node for all endocrine systems, in invertebrates.
Functions of the Human Endocrine System are:
The endocrine system controls a variety of body functions through hormone release. Hormones are built by the endocrine system's glands and pass throughout the bloodstream to various organs and tissues in the body. Hormones then command these organs and tissues about how to act.
The Endocrine System is in charge of the following bodily functions:
- Metabolic rate
- Development and growth of a human being
- Reproduction and sexual function
- Heart Rate
- Blood pressure
- The appetite is the need to eat
- Controls cycles of sleep and wakefulness
- Controls the temperature of the body