Answer:
Cold water can hold more dissolved oxygen than warm water. In winter and early spring, when the water temperature is low, the dissolved oxygen concentration is high. In summer and fall, when the water temperature is high, the dissolved-oxygen concentration is often lower.
Explanation:
The correct answer is A.
The use of antibacterial drugs can cause modifications in the genetic material of the concerned bacteria. If the genetic material of the bacteria are modify, that means they have undergone mutation. Because the base sequence of the normal and that of the mutated gene is different, antibiotic will not be able to recognize the bacteria again and thus will not be able to attack it.
Answer:
Western blot should be performed
Explanation:
Generally ELISA test is sensitive to elevated antibodies levels in the blood. Because HIV infection is characterise with increases in antibodies levels(HIV-antibodies levels)of the body, it is usually the first screening test for HIV,however it is also sensitive to elevated antibody from any other infection apart from HIV. Therefore for confirmation, the procedure is to run a second ELISA test, to determine if the antibody rise was due to HIV or not. If the second test turns positive, then Western blot can be applied.
The Western blot through secondary and primary antibodies binding , separates the investigating antibodies, and identity the specif HIV antibodies present to give a positive HIV-antibody, confirming ELISA positive test.
Thus for confirmation of HIV specific antibodies of the blood; ELISA test followed by Western blot is ideal
Trophic levels go by,
Producer (The nuts)
Primary Consumer (Squirrels)
Secondary Consumer (Raccoons)
Tertiary Consumer (Bear)
So squirrels would be at a lower trophic level.
Hope his help :)