The accumulation of several mutations in the main gene on the virus's surface may be able to give H7N9 the ability to spread like human flu viruses do, passing from person to person through coughing and sneezing.
The general definition of a gene is some heredity that is passed on from a parent to an offspring. Scientifically speaking, the transfer involves a sequence of nucleotides that forms part of the chromosome. This sequence of nucleotides is a DNA.
Thus, the answer would be
A. a segment of DNA
Answer:
its gives us oxygen witch most thing take to stay alive
The name of the tear collecting structure under the skin near the bridge of the nose is the lacrimal sac. The lacrimal sac is part of the lacrimal drainage system or the lacrimal apparatus. The tears are produced in the lacrimal gland and will drain through a hole near the lower palpebral conjuntiva called the puncta which serves as the entrance in the lacrimal system. The tears will now enter the canalicula which serves as the passage way from the puncta to the lacrimal sac. Lastly, the tears in the lacrimal sac will drain to the nasolacrimal duct and to the nose. This also explains why we get runny nose when we are crying.
