Answer:
They are clastic sedimentary rocks
Explanation:
Sandstones, siltstones and shales are all clastic sedimentary rocks.
Clasitc sedimentary rocks are derived from other rock types.
These rock types typically forms from the suspended and bed load of erosion. The weathering of rocks provides the materials that forms these rock types.
The difference between the three rock types is based on their size. Shales are the finest while sandstones are made up of sandsized particles. Siltstones are in the middle.
The concept presented to explain the origin of eukaryotic cells form a bacterial cell parasitized by another descendant cell is called endosymbiosis.
<h3>What is the endosymbiotic theory?</h3>
The endosymbiotic theory is a well-sustained theory in biology about the origin of eukaryotic cells.
According to this theory, eukaryotic cells emerged by endosymbiosis between primitive eukaryotic cells and bacteria that converted into mitochondria and chloroplast organelles.
The endosymbiotic theory is well sustained in several scientific observations such as the existence of DNA in mitochondria and chloroplasts that is independent of nuclear DNA, the size of ribosomal units, etc.
In conclusion, the concept presented to explain the origin of eukaryotic cells form a bacterial cell parasitized by another descendant cell is called endosymbiosis.
Learn more about endosymbiosis here:
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The answer is A. The <span>eggs do not have a shell to prevent water loss.
Toad's eggs do not have a shell, like reptile eggs or bird eggs. Shell is important because it protects eggs from drying out if they are laid in the land. </span><span>Toads lay eggs in a jelly-like glycoprotein. </span><span>Thanks to glycoprotein around toad's eggs, contact with water is maintained all the time so that eggs don't die. </span>
The physical characteristics that determine the exhistance of organisms in aquatic enrironments relate to its pH (which is whether it's acid, neutral or basic), the water clearance (which refers to the particles diluted in it, the presence of toxic substances, etc), the presence of predators (bio chain) and also if there's enough food for the organisms to live, to reproduce and if the water temperature allows them to subsist or if they need to migrate within a year, due to the natural changes.