The answer is the endogenous opiate.
The human body naturally produces its own opiates like substances and uses them as neurotransmitters. These substances include endorphins, enkephalins, and dynorphin, often collectively known as endogenous opioids. Endogenous opioids modulate our reactions to painful stimuli.
A parasite moving between individuals other than parents and their offspring uses
horizontal transmission.
Horizontal transmission is the transmission of infections between (parasites) that are not in a parent-child relationship (vertical transmission). Horizontal transmission may include the carriers or <span>vectors which are other species. Transmission, in that case, occurs via the bite of the vector (an infected organism), like in malaria.</span>
Im not 100% sure but the best answer I can give is Prokaryotes because they came to be around the time oxygen did as well.
Sickle cell anemia is a genetic condition that distorts the shape of the hemoglobin. This reduces the capacity of the red blood cells to carry oxygen. Another effect is that the distorted red blood cells come together forming a heavy and compact collection of cells that can block the flow of blood. The sedimentation rate is increased by sickle cell anemia.
Answer: B
Explanation:
They inject their DNA into the cell, which reprograms that cell to become that virus. This is why viruses are so deadly and can spread throughout the body and to others easily, and efficiently.
