<span><span>Hi,
The two major components of the tobacco mosaic virus were:
1. Protein Coat/Capsid: Each rod consists of about 2130 elliptical protein subunits (capsomers). They are closely packed together and arranged in a helical fashion
</span><span>2. Nucleic Acid: It is a single-stranded RNA helix having a diameter of 80 Å.
Hope I helped :))))</span></span>
What are the answer choices?
Answer:
Because older cultures of gram-positive bacteria tend to lose their ability to retain crystal-violet in the peptidoglycan of their cell walls and can be confused with gram-negative bacteria.
Explanation:
Gram staining is used to differentiate between two major groups of bacteria. Gram-positive and gram-negative, these bacteria differ in the amount of peptidoglycan in their cell walls. Gram-positive bacteria have a higher amount of peptidoglycan, which absorbs the violet crystal complex used in gram staining, staining them purple/violet. Old cultures of gram-positive bacteria tend to lose the ability to retain the violet crystal and are stained by safranine, staining them red/pink and appear to be gram-negative.
Answer:
B. The father did not contribute a sex chromosome to his daughter due to nondisjunction of the sex chromosomes. The daughter is XO and her only X chromosome came from her mother, who was a carrier.
A.The mother's X chromosomes failed to separate during meiosis, and the daughter inherited two X chromosomes with the Lesch-Nyhan mutation. The father contributed no sex chromosomes.
Explanation:
As seen in the question above, a little girl was diagnosed with Lesch-Nyhan syndrome, which is an X-linked recessive condition caused by a mutation in the HPRT1 gene responsible for purine metabolism.
The little girl's parents do not have the syndrome, and no one in the little girl's paternal family presented this syndrome, however, we know that the maternal grandfather of the little girl's mother had the syndrome, which means that it was the mother's genetic material that contributed to the development of the syndrome in the little girl. This was because the little girl did not receive any X chromosomes from her father, but she inherited the two X chromosomes from her mother that coded for the Lesch-Nyhan mutation. This happened because the mother's X chromosome disjuction did not occur during meiosis I.
As shown above, the father did not contribute any sex chromosomes to his daughter, which means that the daughter is XO and her only X chromosome came from her mother, who was a carrier.
