Answer:
A
Explanation:
All living organisms ranging from unicellular prokaryotes to multicellular eukaryotes contain genetic material (DNA). This genetic material is usually found on structures called CHROMOSOMES. Although, the chromosomes are contained in the genome of all living organisms, there are differences.
The genetic material of the bacteria (a typical prokaryote) is a single DNA molecule that makes up its single circular chromosomal material, unlike in eukaryotes that contains double-stranded DNA molecules on linear chromosomes. This single circular chromosome of bacteria is found naked in a region of their cell called NUCLEOID, as they do not possess a membrane-bound nucleus that houses it (a unique characteristics of eukaryotes). 
The mitochondrial and Chloroplast DNA mentioned in the other options are all components of eukaryotic cells. Bacteria, as a prokaryote does not contain this organnelles. Hence, they are not single replica.
 
        
             
        
        
        
Answer:
The above paragraphs describes that how salt- and fresh-water fish regulates their osmoregulation. Hence, the correct answer would be c. have adapted to deal with osmosis.
Osmosis is the process by which solvent's molecule move from region of low concentration (hypo-tonic) to the region of high concentration (hyper-tonic) through a semi-permeable membrane. 
In sea-water fishes, the body fluids are hypo-tonic to the surrounding water and thus water is kept moving out of their gills. In order to prevent the excess water loss they need to drink water constantly and excrete concentrated urine.
In contrast, fresh-water fishes body fluids are hyper-tonic to surrounding water and hence, water keeps entering in their body through gills. So, in order to prevent excess dilution they absorb salt from surrounding with the help of gills and also their bodies reabsorb salt from urine. 
 
        
                    
             
        
        
        
Answer: hydrosphere, cryosphere, geosphere
Explanation:
 
        
                    
             
        
        
        
1) The first stage of mitosis is actually just the condensing of the chromosomes.
2)They start out as double, then gradually get to the same number.
3)Cell actually spend the most time in the G phase of the cell cycle.
        
             
        
        
        
Throughout the history of nursing research, most studies have focused on clinical problems. TRUE