Answer:
Unlike typical mammalian red blood cells, those from amphibians, such as frogs, contain a DNA-bearing nucleus that is visible in the center of the cell. The circulatory system of amphibians is rather unusual, their hearts having three chambers, two atria, and a single ventricle.
NegativePositive
Positive
The design of the amphibian circulatory system is curious because blood accumulates oxygen in the lungs and is then returned to the heart before being pumped into the rest of the circulatory system. Therefore, a mixing between oxygenated and deoxygenated blood occurs as blood returning to the heart from the lungs is mixed with incoming blood from the body. Frogs handle this situation by having a very slow metabolism and by absorbing some oxygen through their skin. In addition, the ventricle does have some directional control over the distribution of the blood.
Negative
The presence of a nucleus in amphibian red blood cells allows researchers easy access to large quantities of amphibian DNA. Frog blood has both a solid and a liquid portion. The liquid plasma carries solid elements such as red and white blood cells. Blood can be collected from frogs and the red blood cells isolated by centrifugation. After removal of the residual plasma, purified cells can be treated with specific enzymes and detergents to digest the cellular envelope and release DNA from its protein complex. The DNA is then useful for scientific studies and experiments.
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Explanation:
Answer:
C
Explanation:
Becuase fom a vaccine you are recieving antibodies by another animal or human donor.
D is unlinkely since it describes how the mother is nursing the baby, so nothing directly mentioning of the baby recieving any antibodies. The other options also talk about how the body creates its own antibodies, which isn't passive immunity.
Answer:
overreacts to an antigen
Explanation:
Allergies to substances are as a result of immunological dysfunction.
The second and third one I believe
It is the same as creating more pests or setting up dominant species which upset the ecological food pyramid leading to decimation of trophic levels or predators and energy cycling. Fishes feed on microscopic algae and animals the primary base of the food chain in water, if they are not checked they will choke the rivers and oceans causing toxic waters. Fish feed to contain them, in the process they grow and increase in numbers but their population is checked by bigger fishes and so on till it reaches a top predator which is usually a large animal.
