The correct answer is D. Mutation causing uncontrolled cell division.
Mutation is termed as the alteration of sequence of nucleotides which is permanent to organisms or extrachromosomal DNA or virus.
During DNA replication mutation may result from different errors. For example, during meiosis we can say that the result of mutation can be harmful if mutation can change proteins which are being produced by a gene.
Here I provide you some examples of modified stems:
<u>Bulb:</u> discoid stems that have a single apical bud surrounded by numerous cataphiles, and in their part I have adventitious roots. Its function is the reserve.
<u>Tuber</u>: They are portions of stems with irregular growth, which forms tuberosities due to the large accumulation of reserve substances.
<u>Cladodes: </u>are flattened stems, very thick, green leaves look alike and have photosynthetic function.
<u>Stem tendrils:</u> they are filamentous stems, which can be rolled up so that the plant can climb grasped of various objects, which is useful when the plant needs to look for the greatest possible luminosity, especially in areas where shadows predominate.
Phylloclades: Stems sheet form with limited growth, like a leaf, green and photosynthetic color.
The red blood cell is normally circular shaped but for sickle cell anemia the red blood cell is literally sickle shaped so the surface area decreases and less amount of oxygen is stored by the sickle shaped cell thus resulting in low O2 content
The effect of a neurotransmitter is based on the properties of the receptor more than the neurotransmitter.