Fresh water is any body of water with a low salt concentration. Organisms in fresh water various challenges which includes; Osmotic concentration such that fresh water is permanently dilute and most cells cannot function at this concentration of ions. Varying temperatures, variation in oxygen levels and reproduction and life cycle due to permanence of habitat and physiological difficulty of regulating osmotic concentration in larvae and juveniles.
Because Yuki started off with a bowl of ice right. She sat in the room and watched the ice melt, the ice melts when the temperature is to hot then she heats up the water on a burner and it vaporizes when the water gets to hot.
Answer: we can make observations directly by seeing, feeling, hearing, and smelling, but we can also extend and refine our basic senses with tools: thermometers, microscopes, telescopes, radar, radiation sensors, X-ray crystallography, mass spectroscopy, etc. And these tools do a better job of observing than we can!
These unsegmented worms have a full digestive system even when parasitic.
The bear affects the ecosystem by eating plants and animals which lowers invasive species levels.
