Measuring photosynthesis via the production of oxygen. Oxygen can be measured by counting bubbles evolved from pondweed, or by using the Audus apparatus to measure the amount of gas evolved over a period of time.
Answer:
When an E.coli cell is infected by multiple phages,they will take either lytic or lysogenic pathway.
Explanation:
When lambda phage bacteriophage infects an E.coli,it can either undergo lytic cell growth and lyse the host cell or enter lysogenic pathway.
The operator region of lac operon in E.coli contain single repressor binding site whereas the lambda operators 
and 
each contains 3 repressor binding sites (
and 
) that are differently occupied under different conditions.
The differential affinity of lambda repressor for the three binding sites in these operators play an important role in the maintenance of lysogenic state of lambda prophage in E.coli.
The lytic development occurs in cells infected with lambda phage that carry 
gene.
In contrast,lysogeny will occur in bacteria that infected with lambda phage that harbor a deletion of Cro gene.
Barrier island refers to the off shore deposit of sands and sediments which runs parallel to the coast line. Off shore is the first line of defense against storm wind and waves, thus they must be protected.
Communities that are far from the barrier island will be committed to preserving it if the following information are given to them: barrier islands have very high beneficial impacts on distant communities, this is because wet land will not exist without the contribution of barrier island which keep the coast away.
A, B, and C are all forms of asexual reproduction.
Answer: salt
Freshwater is defined as having a low salt concentration, usually less than 1%.
Explanation:
Freshwater refers to the bodies of water that contain very low levels of dissolved salts. So, freshwater are unique for their low salt content (about 0.5% of salt) compared to the sea water with high salt content.
Examples of freshwater include rivers and spring
