Answer:
Mutation is important as the first step of evolution because it creates a new DNA sequence for a particular gene, creating a new allele.
Explanation:
Answer:
James Watson and Francis Crick solved the structure of DNA. Rosalind Franklin and Maurice Wilkins, also contributed to this discovery.
Explanation:
Answer: B (Color blindness)
Explanation:
Typical red-green color blindness in human patients is caused by mutations on genes located in the X chromosome. These mutations act in a recessive manner. Since females have two X chromosomes, the presence of a mutation in a single one of them does not normally result in color blindness. Males, in contrast, have a single X chromosome and therefore the presence of a mutation is likely to cause the disease.
About the other options: Down‘s syndrome is a numerical chromosomal anomaly, not related to sex. Human blood type is a codominant trait. Finally, tail length in dogs is a polygenic trait not amenable to classic Mendelian analysis.
Answer:
Parasympathetic nervous system
Explanation:
Parasympathetic nervous system (PNS) along with sympathetic nervous system (SNS) makes autonomic nervous system (ANS). ANS controls the functioning of internal processes like digestion rate, heart rate, respiratory rate etc. During a threat or stressful situation SNS is activated. It increases heart rate, respiratory rate and directs blood flow towards peripheral muscles as a part of "fight or flight response". When the situation becomes normal, PNS is activated which restores all the vitals as a part of "rest and digest" mechanism.
Since here Byron almost got into an accident, he was scared a lot due to which his SNS was activated. Eventually when he realized that he is out of danger, his PNS got activated which returned his heart rate and blood pressure to normal levels.
