Answer:
b
Explanation:
The answer is B becuase "where do people buy tools is not a scientific question, and neither is C.
<span>Neils Bohr </span>developed a model of the atom (Bohr model) to explain how the structure of the atom changes when it undergoes energy changes. His major idea was that energy of the atom was quantized (this means that the atom could only have very specific amounts of energy) and the amount of energy in the atom was related to the electrons possession in the atom. In the Bohr model, electrons travel in orbits around the nucleus. The further the electron from the nucleus the more energy it has. Bohr used Planck's quantum concept of E=hv.
Answer:
The effiency decreases at higher altitudes
Explanation:
The higher up a person is on a mountain, the thinner the air is due to the lack of plants that can grow. An example of this is Mount Everest. At a certian point on the mountain, called the "Death Zone", the air is too thin to supply enough oxygen to the human body to survive. That's why they bring oxygen tanks with them on their adventures.
Answer:
The fewer number of T cells a person has, the more chances to be affected by an opportunistic infection. When the number of T cells reaches 200 cells/µl, the person is at risk of being infected by other infections.
Explanation:
The whole immune system of a person who is infected with HIV infection seems to be severely affected. When the person is not treated or the disease is in a very advanced stage, the depletion of the T- cells turns to be very sharped, especially CD4+ T cells. At this point, the immune system can not resist the attack of other microorganisms. The <em>lower is the number of CD4+ T Cells, the higher possibility the person has to be attacked by opportunistic infections. </em>
Classically, it has been suggested that opportunistic infections appear after the CD4 + T lymphocytes reach very low levels, such as 200 cells/µl. The number of circulating T cells can be used as an indicator and a measure of global "immune competence", and the previously mentioned amount of CD4 + T cells is an accepted universal reference used to predict the risk of having one of these opportunistic infections.
Terms matched with the right definitions.
1. An organism that can make its own food – Autotroph
2. A symbiotic relationship between two organisms in which one species benefits and no effect is apparent to the other species – Commensalism.
3. A cell that has a membrane-bound nucleus and/or organelles as its major characteristic -Eukaryote.
4. The study of organisms that are too small to be seen with the naked eye - Microbiology.
5. A disease-causing organism - A germ pathogen.
6. A one- or few-celled organism with chromosomes; may have characteristics of both animals and plants – Protist.
An autotroph is an organism that produces its own food from simple substances available in its environment. Autotrophs usually use inorganic chemical reactions or light energy in producing their food and are usually the producers in a food chain. Examples of autotrophs are plants and algae.
Commensalism is a type of relationship between organisms of two species where one organism benefits from the relationship and the other organism is not affected by it (neither benefits nor harmed).
