In biochemistry, chemosynthesis is the biological conversion of one or more carbon-containing molecules (usually carbon dioxide or methane) and nutrients into organic matter using the oxidation of inorganic compounds (e.g., hydrogen gas, hydrogen sulfide) or methane as a source of energy, rather than sunlight, as in photosynthesis. Chemoautotrophs, organisms that obtain carbon through chemosynthesis, are phylogenetically diverse, but also groups that include conspicuous or biogeochemically-important taxa include the sulfur-oxidizing gamma and epsilon proteobacteria, the Aquificae, the methanogenic archaea and the neutrophilic iron-oxidizing bacteria.
Many microorganisms in dark regions of the oceans use chemosynthesis to produce biomass from single carbon molecules. Two categories can be distinguished. In the rare sites at which hydrogen molecules (H2) are available, the energy available from the reaction between CO2 and H2 (leading to production of methane, CH4) can be large enough to drive the production of biomass. Alternatively, in most oceanic environments, energy for chemosynthesis derives from reactions in which substances such as hydrogen sulfide or ammonia are oxidized. This may occur with or without the presence of oxygen.
Many chemosynthetic microorganisms are consumed by other organisms in the ocean, and symbiotic associations between chemosynthesizers and respiring heterotrophs are quite common. Large populations of animals can be supported by chemosynthetic secondary production at hydrothermal vents, methane clathrates, cold seeps, whale falls, and isolated cave water.
It has been hypothesized that chemosynthesis may support life below the surface of Mars, Jupiter's moon Europa, and other planets.[1] Chemosynthesis may have also been the first type of metabolism that evolved on Earth, leading the way for cellular respiration and photosynthesis to develop later.
That’s probs to much
        
             
        
        
        
Lactase refers to an enzyme that can dissociate lactose sugar into glucose and galactose. This enzyme plays an important role in the digestion of milk that comprises high lactose sugar. In case, if a mutation occurs in the gene codon of lactase, then two possibilities can take place. These are as follows:  
1. Loss of mutation: In this case, the person becomes lactose intolerant because of mutation in lactase gene codon. Due to this, there is low mRNA expression and thus low production of the enzyme lactase. This is also known as lactase non-persistent phenotype.  
2. Gain in mutation: In this case, the person gain an increase in mRNA expression of the lactase gene, thus more production of lactase takes place than usual. This kind of individual exhibits lactase persistent phenotype.  
 
        
             
        
        
        
The first trophic level 
they would want to eat the primary producers, which are located at the first trophic level. due to the 10% rule only 10% of the energy from the previous trophic level is passed on.
        
             
        
        
        
Explanation:
The hydrologic cycle describes the pilgrimage of water as water molecules make their way from the Earth's surface to the atmosphere, and back again. This gigantic system, powered by energy from the sun, is a continuous exchange of moisture between the oceans, the atmosphere, and the land.
 
        
             
        
        
        
Answer:
B it lives inside or on a host 
Explanation:
that is the definition of parasite