The correct answer is (B) Photosynthesis and diffusion from the air
Dissolved oxygen enters the water from photosynthesis and through air. The The aeration of water can be caused by wind. From the air oxygen diffuse into the water and gets mixed in the it through circulation. The oxygen is also produced as a waste product of photosynthesis from blue-green algae, phytoplankton, etc which is added in water.
Answer:
(A) Bioaccumulation
Explanation:
When the concentration of certain substances in the bodies of the organisms of various trophic levels keeps on increasing as they pass through the food chain, the process is called bioaccumulation or biomagnification.
Most of the organic non-biodegradable pollutants/chemicals exhibit bioaccumulation. Being insoluble in water, these chemicals are accumulated in the fat tissues of the organisms.
As the predator feeds on the prey having a non-biodegradable chemical in its tissues, the chemical enters the body of the predator.
As these chemicals pass through the food chain, there is a gradual increase in their concentration stored in the living tissues of the organisms. Therefore, the top consumers exhibit maximum bioaccumulation of contaminants in a food chain.
Answer: The answer is that the phenotypic ratio among phenotypes produced from an F1 X F1 dihybrid cross is 9:3:3:1.
Explanation:
Independent assortment of genes explains how alleles on different chromosomes arrange independently of one another during gamete formation.
So, a dihybrid cross involving TWO characters (e.g Seed color & seed shape) would have its respective alleles DISTRIBUTED whether dominant or recessive, for crossing to occur and yield varying proportion of offspring in the well spread ratio of 9:3:3:1; making it a consequence of independent assortment of genes
Out of the options I would have to say Penetrating Keratoplasty, I am not sure
Answer:
B. differential
Explanation:
The culture medium is a chemical preparation that has the necessary nutrients for microorganisms of a given biological sample to multiply, allowing its study, identification and analysis. The main components of a culture medium are sources of carbon, energy (sugars), nitrogen, phosphorus and minerals.
There are several types of culture medium, among them we can mention the differential culture medium, which is the type of medium that is being used in the experiment shown in the question above. The differential culture medium allows the distinction between various genera and species of similar microorganisms. This distinction is possible because this type of culture medium has substances that allow for a presumptive differentiation, evidenced by the color change or the morphology of the colonies.