<span>The ischemic penumbra can maintain metabolic demand with marginal blood flow from collateral circulation for a maximum of 50% before increasing in size. A penumbra is the area where the flow of blood at about 25 - 50% can maintain normal metabolic demands for 6 - 8 hours only. When it continues to increase, the human cells will die and other neurological activity will be suspended causing the person to die slowly.</span>
Parasites benefit their hosts is the true statement. Parasitism is a symbiotic relationship in which one organism (the parasite) benefits from another organism and this other organism is harmed by the parasite.
The others aren't true because:
- the organism that is harmed doesn'y adapt and evolve it still is vulnerable
- it is a fact that parasites change from hosts
- phoresy is an association between two species in which one transports the other. This does not include killing the host (is possible, but it is not a condition under which you can call something a phoresy).
Answer:
1. Supplying
2. Taking
Explanation:
Food chain is a linear relationship between organisms that depicts the flow of energy from one organism to another. In a food chain, organisms are arranged in trophic levels where arrows pointing to the right direction (➡) are used to show that the organim the arrow is pointing to eats the organism behind it.
Hence, according to this question, arrows in a food chain point from the organism SUPPLYING the energy to the organism TAKING the energy.
Answer: white blood cells
Explanation: They fight off the bad bacteria.
