Gametes are an organism's reproductive cells. They are also referred to as sex cells. Female gametes are called ova or egg cells, and male gametes are called sperm. Gametes are haploid cells, and each cell carries only one copy of each 
 
        
             
        
        
        
Answer:
Substrate. The substrate is the surface on which the river organisms live. It may be inorganic, consisting of geological material from the catchment area such as boulders, pebbles, gravel, sand or silt, or it may be organic, including fine particles, leaves, wood, moss and plants.
 
        
                    
             
        
        
        
 Edwin Hubble's observation of galaxies revealed that the light received from them were red-shifted, indicating that they are moving away from us. And the seemingly farther away a galaxy was, the greater its red-shift. This can only be explained if a all the galaxies were expanding outward. Determining the exact distances to the other galaxies was a problem, however, until the Hubble space telescope. It had high enough resolution to identify Cepheid variable stars in other galaxies, and accurately determine their distance, and therefore the expansion rate of the universe.eelfins <span>· 
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Answer:
Lactaid is an enzyme supplement which help digest lactose present in milk.
Explanation:
Lactaid is an enzyme supplement drug which help to digest lactose present in milk. Lactose enzyme is produced naturally by the body but some people are lactose intolerant whose body produce less amount of lactose. So these supplements will help them to digest lactose.