The answer is true...hope that helped
In a sample of double-stranded DNA, if the nitrogenous base guanine is 19%, then the nitrogenous base adenine will be 31%
Explanation:
In a double-stranded DNA, the four nitrogenous bases bind and pair together. The purine bases guanine (G) and adenine (A) pair with pyramidine bases cytosine (C) and thymine (T) respectively. The pairing will be between G-C and A-T bases.
According to Chargaff’s Rule, the percentage of each nitrogenous base will be equal in a pair. So the percentage of G will be equal to percentage of C and the percentage of A will be equal to percentage of T.
So if the guanine percentage is 19%, then applying Chargaff’s rule, cytosine will also be 19%
The remaining 68% will be shared with the adenine and thymine pair, of which adenine will be of 31% according to Chargaff’s rule.
All of the choices are the challenges that countries face in limiting the spread of communicable diseases. The lack of available healthy food would force countries to increase its reliance on food producers abroad, which could mean food contamination during harvesting, storage, processing, and transport.
Next, the increase of worldwide travel has also increase the risk of infectious disease where travelers encounter microbes in the new environment and can have direct contact with exotic wildlife.
Moreover, the decrease of available clean water is a source of communicable diseases because inadequate sewage and water management systems could incubate disease vectors such as mosquitoes and rats. Also, improper sanitation services spread diarrheal diseases.
Lastly, the increase in migration of infected animals are also a good source of infectious diseases for animals that are introduced in new environment can disrupt ecosystems in ways that increase the potential for infectious disease outbreaks such as Ebola and Lyme diseases.
Answer:
toxic people exist to make our lives terrible and remind us of who our real friends are
Explanation:
They also exist to help us to not feel as bad when we're mean to them
Cystic fibrosis - causes a mucus build up on the lungs, that coats the breathing tubes
