Answer is A. A Hox gene
Hox genes are a series of genes that controls the differentiation of cells and tissues in an embryo by turn on and off other genes. If Hox genes express incorrectly, a major changes in the morphology of the individual can be seen.
Let’s understand this with an example: The Ultrabithorax, a Hox gene determines the Third thoracic segment in <em>Drosophila melanogaster</em>. Third thoracic segment displays a pair of legs and a pair of reduced wings used for balancing. In the mutant<em> Drosophila</em> the functional Ultrabithorax protein is absent. Due to this mutation, the third thoracic segment now expresses the same structures found on the second thoracic segment, which contains a pair of legs and a pair of wings which are fully developed .
Hope this helps!
A collision of two galaxies has left a merged star system with an unusual appearance as well as bizarre internal motions. Messier 64 (M64) has a spectacular dark band of absorbing dust in front of the galaxy's bright nucleus, giving rise to its nicknames of the "Black Eye" or "Evil Eye" galaxy.
Fine details of the dark band are revealed in this image of the central portion of M64 obtained with the Hubble Space Telescope. M64 is well known among amateur astronomers because of its appearance in small telescopes. It was first cataloged in the 18th century by the French astronomer Messier. Located in the northern constellation Coma Berenices, M64 resides roughly 17 million light-years from Earth.
Image Credit: NASA and The Hubble Heritage Team (AURA/STScI); Acknowledgment: S. Smartt (Institute of Astronomy) and D. Richstone (U. Michigan)
Last Updated: Feb. 16, 2016Editor: NASA Administrator
The answer is e. Calcitonin, Aldosterone and Atrial natriuretic peptide.
The calcitonin is a hormone secreted by the thyroid gland. Calcitonin is involved in the regulation of the levels of calcium and phosphate in the blood. Aldosterone is a hormone secreted by the adrenal gland. It is essential for maintaining the store of sodium in the kidney, salivary glands, sweat glands and colon. Atrial natriuretic peptide (ANP) or Atrial natriuretic factor (ANF) is a peptide hormone synthesized, and secreted by cardiac muscle cells in the heart. ANP is involved in the regulation of sodium levels in the cells of the heart.
