Answer: C) 3
Explanation:
If you work through the punnet square for the two rabbits, only four of the sixteen possibilities has red eyes, and only three of those four has gray fur as well. So, three of the 16 rabbits have gray fur and red eyes.
Based on the broth left on an open flask experiment, wherein the boiled broth was placed in two flasks (one flask with straight neck and the other flask has a bent neck) and exposed to open air at room temperature for several weeks.
The broth within the straight neck flask has changed its appearance. It became discolored and cloudy. Whereas, the broth in the bent neck open flask still remains the same.
These results would then support the conclusion that germs in the air were able to fall unobstructed towards the straight neck flask and contaminate its contents. While, the bent neck of the 2nd open flask acted as a trap for the germs, preventing the germs from contaminating the broth. Further emphasizing that germs can only come from other germs and not from spontaneous generation.
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 .
"Males who inherit the mutation get the disease because they have no second dystrophin gene to make up for the faulty one. Early in the embryonic development of a female, either the X chromosome from the mother (maternal X) or the one from the father (paternal X) is inactivated in each cell."
(courtesy https://www.mda.org)
