The air that we breathe is mostly made up of nitrogen (78%). 21% is oxygen which is needed for animals and humans in respiration and 0.03% is carbon dioxide which is needed for plants to make energy in a process called photosynthesis. The bit that is left is made up of rare gases like helium and argon and methane.
Answer: B. guanine
In a double helical structure of the DNA, the two strands of the DNA lies in a anti-parallel conformation. The complementary strands of the DNA follows the complementary base pairing rule given by Chargaff. It states that any cell of the organism should have 1:1 ratio of the pyrimidine and purine basis. The amount of thymine is equal to adenine and the amount of cytosine is to guanine. Adenine forms double hydrogen bond with Thymine and Cytosine forms triple hydrogen bond Guanine.
Answer: a higher level of antibody
Explanation: whenever any foreign particle enters in the body, the immune system activates. The body responds according to the type of foreign particle. If plasma cell count is higher in lymph then the antibody level also higher. Because plasma cells are responsible for the production of antibodies. Whenever the plasma cell level raises automatically antibody level also raise. For example in the case of multiple myeloma plasma cell level abnormally increases and also antibody level raised to an abnormal level.
Answer:
This scale of evolution occurs above the level of the species. Fossils provide evidence for evolution at this scale. The evolution of the horse family. Micro evolution is evolutionary change within a species or small group of organisms, especially over a short period. And Macro evolution is major evolutionary change. The term applies mainly to the evolution of whole taxonomic groups over long periods of time.
Explanation:
Answer: "The amount of entropy of any thermodynamically isolated system tends to increase over time until it reaches a maximum value"
Explanation:
The second law imposes limits on heat conversion processes at work. The result of the second law is that the complete conversion of heat to work is impossible. One must, however, note that there is no objection to converting any amount of work into heat, but note that the reverse is not possible. The opposite is not possible.
Historically, the content of thermodynamics began with the study of the properties of basic thermal machines. Thermal machine means any device which, operating in cycles, absorb heat, convert part of it into work, and reject the rest. Placed in terms of limitation of thermal machines, the second law can be established by saying that none of them can absorb heat and make it fully work. This is the practical orientation of the second law. Undoubtedly, the science of thermodynamics began with the analysis of the problem of how to build the best and most efficient thermal machine. This task was performed brilliantly by French engineer Sadi Carnot, and this is one of the few cases where engineering has contributed fundamentally to physical theory.
