Answer:
Fraternal twins can be different genders because they are two completely different eggs getting fertilized; but even two same gender fraternal twins do not look completely alike. Whereas for identical twins since one egg is splitting into two, the two cells have the same exact DNA make up and chromosomes.
I also believe the technical part of it is to do with genetics, like ressesive and dominant genes, because they can be the same gender, ex. both girls and one has blue eyes, fair skin, and blonde hair, the other twin has brown eyes, black hair and tan skin. The parents could be part of the genes but there is also grandparents maybe the mom's mom has blonde hair and blue eyes, with fair skin. But the dad he has brown eyes, black hair and tan skin. The moms genes were recessive, but the grandma's genes were dominant.
I tried to explain it as best as I could I hope it helps!
Answer:
A. What is your diagnosis here?
As per symptoms and incident of puncturing left arm with nail from an old barn indicates it can be infection of Clostridium tetani causing disease tetanus.
When such kinds of wound occurs, there should be injection of tetanus immunoglobulin (TIG) immediately. This injection contains antibodies against Clostridium tetani which can kill the microorganism. It should be injected as soon as possible. But this is short term immediate medication.
B. What is the proper treatment of this problem?
For the treatment antibiotic penicillin, metronidazole or tetracycline can be given, it prevents multiplication of bacteria and production of neurotoxin from bacteria. these neurotoxins are responsible for muscular spasms. Along with antibiotic some anticonvasculants, muscle relaxants can be given to reduce spasms, anxiety.
C. How could this have been prevented?
This infection can be prevented by giving its vaccine in childhood itself. Vaccine is given in the form of DTaP vaccine (diptheria, tetanus toxoid, acellular pertusis). It is given in 5 shots. It is given in the arm or thigh when child is at 2 month age, 4 month age, 6 month age, 15 to 18 month age, 4- 6 years of age.
Explanation: