After sitting for many hours during a trans‑pacific flight, a passenger jumps up quickly as soon as the "fasten seat belt" light is turned off, and immediately falls to the floor, unconscious! within seconds of being in the horizontal position, however, consciousness is restored. select the option that completes the explanation of what happened.
upon standing, there is a time lag before the person’s heart responds to the:
o increased downward force of the top of her head on her blood. lying horizontally removes the downward force.
o increased pressure difference between her feet and her head. lying horizontally reduces the pressure difference.
o reduced fluid density in her brain, which causes a lack of oxygen. lying horizontally restores the proper fluid density.
o rush of blood and other fluids up into her head. lying horizontally equalizes her fluid levels once again.

increased pressure difference between her feet and her head. Lying horizontally reduces the pressure difference.

Explanation:

The autonomic nervous system controls heart function to adapt to the effect of body positional changes. In some circumstances it takes a few seconds. So even if the passenger would have been held upright she would have recovered consciousness. The horizontal position sped up things

i believe the correct answer is the virus gets an envelope that contains host molecules when it leaves the host cell.

explanation:

during the bidding/release stage of a virus, it encapsulates itself with part of the membrane of the host cells in this case the cells of the monkey and is the reason as to why the scientist found the genetic material of the monkey on the viral cell surface.

further explanation

to understand this answer, we have to know the cycle a virus undergoes to replicate. a virus is basically a bunch of genetic material enclosed in a capsule and lacks any machinery or organelles to ensure their survival so they must enter a host cell in order to get the environment needed to survive. some viruses enter and lyse(destroy) the host cell after they have replicated and undergo the lytic cycle while some enter and leave the cell intact after replicating and these undergo a lysogenic cycle. to enter the cell, they undergo the first process called attachment by binding to specific receptors and co-receptors on the surface of the host cell. after attaching to the cell, they start the second phase called penetration where virus enters or is engulfed whole by the host cell through a process called endocytosis. it is the same process that a cell takes up materials it needs or pathogens around it. uncoating of the virus then happens after the virus has been engulfed and is the third stage. the virus then undergoes releasing of its genetic material in the host's matrix.   the materials then enter the nucleus and undergo biosynthesis by adding themselves in strands of rna being translated and then copies of the virus are produced in addition to the host genetic material. the material/newly formed viral material then undergoes assembly inside the host cell and form a capsule around them. the virus undergoes the last release/budding stage by binding to the host membrane and pushing outwards. in doing so when they tear away from the host membrane, they pick up the genetic material from the membrane of the host cell to form their envelope.

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level: high school