Answer:
When certain large molecules are unable to move through the membrane without the help of channel proteins
Explanation:
Facilitated diffusion occurs when large molecules that are unable to pass through a membrane on their own make use of channel proteins to move from one side of the membrane to the other. Facilitated diffusion can occur when a liquid on one side of a membrane has a higher osmotic pressure than a liquid on the other side of the membrane, but it isn’t a required feature of facilitated diffusion. Similarly, facilitated diffusion can occur when there’s a large membrane potential present, but it isn’t a required feature of facilitated diffusion. Facilitated diffusion doesn’t require the use of energy, so the presence of ATP is irrelevant to facilitated diffusion occurring.
Answer:KEYSTONE SPECIES
Explanation:
the ecosystem would be extremely different without the key stone specie or cease to exist complete .
Basically a keystone specie is a specie that helps define an ecosystem and if the specie was to die or cease to exist no other specie can take its place and the ecosystem will have to change radically and it'll be forced to introduce a whole a new habitat because the keystone specie has a huge influence on the food web
EXAMPLE :
A keystone specie could be any specie ranging from plants to fungi
Answer
Respiratory and circulatory system work close together with alveoli to provide oxygen to cell.
Explanation
Through the process of respiration when oxygen reaches to lungs and then to alveoli. Here oxygen is diffuse to blood through capillaries by the process of partial pressure diffusion. Oxygen combine with hemoglobin present in red blood cells. Now with the help of circulatory system this oxygen is transported to all other parts of the body where needed.
Answer:
c
Explanation:
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Answer:
<em>The correct option is A) Active transport moves substances against the concentration gradient.</em>
Explanation:
Active transport can be described as the movement of molecules against a concentration gradient i.e from an area of lower concentration to an area of higher concentration.
Facilitated diffusion can be described as the movement of molecules guided by other molecules such as integral proteins. These kinds of movements are a type of passive transport as the molecules move along the concentration gradient from an area of higher concentration to an area of lower concentration.
