Answer:
The correct answer is- 4:0
Explanation:
Marfan syndrome is a genetic problem which affects the connective tissue in the body. The trait for this disease is autosomal dominant which means even one abnormal copy of this gene in the offspring or individual is sufficient to cause this syndrome.
Let S is the allele that is dominant for this syndrome and s is recessive. So if a cross between homozygous dominant(SS) and heterozygous individual (Ss) occurs than all the offspring would have this syndrome.
S s
S SS Ss
S SS Ss
Therefore all 4 offspring would have at least one dominant allele which is sufficient to cause this syndrome. So the phenotype ratio would be 4:0.
The fight or flight system is a reaction that the body undergoes when put in an either stressful or frightening situation. It includes both the nervous and endocrine system.
The sympathetic division of the peripheral nervous system is used in this response as the sympathetic nervous system works up the body, increases the rate of breathing, heart rate, dilates the pupils, produce more sweat and slow the digestion rate. This reaction happens in the flight or fight system.
Answer:
Option C, varicella-zoster virus
Explanation:
The synonym for varicella-zoster virus is VZV and it is responsible for causing chicken pox in primary infection and shingles after the reactivation of latent VZV infection
It is a DNA virus that belong to the group of herpesvirus. All herpesviruses have the capability to persists in the body after primary infection as latent infection. These viruses survive for a short duration in the environment.
Hence, option C is correct.