Answer:
c
Explanation:
Hubble's brilliant observation was that the red shift of galaxies was directly proportional to the distance of the galaxy from earth. That meant that things farther away from Earth were moving away faster. In other words, the universe must be expanding.
Answer:
The cells need water to maintain their metabolic functions, the way water enters through cells membranes is by osmosis.
Explanation:
The cell membrane is a lipidic bilayer composed of phospholipids and embedded proteins. Phospholipids have the characteristic of being amphiphilic which means that possess hydrophilic and lipophilic characteristics. The most common way is by osmosis, that is a mechanism that moves water from high concentration to less concentration of water. In the cell membrane, there are is channels of proteins called aquaporins that facilitate the pass of water through the membrane. Also, as water is a very small molecule without charge, this characteristic allows passing a limit amount of water molecules through the hydrophilic characteristic of membranes.
Answer:
The correct answer is keystone predator.
Explanation:
In sustaining the composition of an ecological community, a keystone species plays an essential function. In the absence of keystone species, the ecosystem would fail to exist and would become drastically different. A predator is a classic illustration of a predator, which inhibits a specific herbivorous species from eradicating the dominant species of plants. In the non-existence of predators, the herbivorous prey would increase enormously and would clean the entire essential plant species, and thus, drastically change the significance of the ecosystem.