Answer:
Density is nearly 3 cabs per hectare
Explanation:
Given -
There are three three intertidal regions.
Area of each intertidal region is 
hectares.
Number of crab in the intertidal regions are as follows -
Intertidal region I - 7
Intertidal region I - 2
Intertidal region I - 6
Sum of crabs in all three regions is equal to
Total area of all three intertidal regions is equal to
hectares
Now density per hectare is equal to total population of crab divided by total area of all the three intertidal regions
Density 
Density is nearly 3 cabs per hectare
The correct answer is high, low.
Arteries are part of the circulatory system and are responsible for carrying blood away from the heart and around the body. The arterial blood is oxygenated and this process ensures that every tissue around the body will receive oxygen and nutrients through this blood flow.
Veins are also part of the circulatory system and are responsible for carrying the deoxygenated blood from the tissues back to the heart.
Venous pressure is much lower than the arterial pressure. More specifically, venous pressure ranges from 5 to 8 mmHg, while arterial pressure ranges from 15 to 30 mmHg.
Answer:
I think its the third one :)
Explanation:
hope this helped :))
* Channel proteins- these are proteins with a hydrophilic pore where specific ions are able to pass through the membrane. Each channel protein is specific to an ion. This is the only way ions can travel through the membrane. They are trans membrane proteins.
* Carrier proteins- these are proteins which allow larger or polar molecules through the membrane. They are trans membrane proteins.
Carrier proteins essentially “carry" signals that are not soluble in aqueous solution through the blood stream to their target cells. Carrier proteins for hydrophilic signals prevent degradation of the signal. Channel proteins are embedded in cell membranes. They often are receptors (though not always), and when activated, allow specific ions to pass through the membrane.
A channel protein is a special arrangement of amino acids which embeds in the cell membrane, providing a hydrophilic passageway for water and small, polar ions. Like all transport proteins, each channel protein has a size and shape which excludes all but the most specific molecules
The carrier protein facilitate diffusion of molecules across the cell membrane. The protein is imbedded in the cell membrane and covers the entire membrane. This is important because the carrier must transport the molecule in and out of the cell.
There are few donor lungs available.<span>In 2010, about 1,800 lung transplants were performed in the United States.
Brainliest please?</span>
