Out of the following given choices;
a. they increase the amount of energy transferred from the
lungs to the blood
b. they increase the flexibility of the lungs as they expand
during inhalation
c. they increase the volume of the lungs, allowing more
oxygen to be inhaled
d. they increase the surface area of the lungs, allowing the
efficient gas exchange
The answer is D. Due to their microscopic nature, they are numerous in the lungs and are also circular-shaped so as to increase the surface area for gaseous exchange.
Other characteristics of alveoli that increase gas exchange are that they thinned-walled (with only a layer of cells) and moist.
In mid-ocean ridge areas, ocean water is cycled through the crust because of the high heat flow in the area. Water in the rock is heated over the magmas, rising up and drawing in cold water from the sides. This process is occurring all over the world, and is the primary means for maintaining ocean salinity in a relatively constant range over the long term, as elements in the sea water when it is heated react with the rocks. There is so much water flow, cumulatively over the entire world, that this process basically buffers ocean chemistry.
Obviously large increases or decreases in salinity can and do occur in isolated basins that do not have free exchange with the open oceans.
<span>Climax community=when the ecosystem reaches its mature state. After every disturbance, the ecological succession will culminate in the climax community. For example, ecological succession triggered by fires in Yellowstone Park culminates in pine forests. Pioneer species are the first species to colonize an area after a disturbance occurs. They reproduce quickly and survive in harsh conditions. For example, lichens.</span>
Answer and Explanation
Mendel selected a group of dwarf plants and sel pollinated them by dusting mature pollen grains onto them. He then collected the resulting seeds and planted them and noticed these seeds germinated and grew into dwarf plants only.
He also selected tall plants and self-pollinated them. the resulting seeds he observed that they grew into a micture of tall and dwarf plants. He took the seeds of tall plants only and repeated the experiments for many generations until he obtained only tall plants.
He then crossed cross-pollinated purebreeds tall garden pea with pure breed variety. He planted the seeds and observed the offsprings were all tall plants. He crossed two of these tall offsprinf from the F1 and planted the resulting seeds. the second filial generation consisted of a mixture of tall and dwarf plants.
He counted these plants and noted that the ratio of tall to dwarf was about 3:1. From this, he postulated that there are now laws governing inheritance.The law of independent assortment and law of segregation.
The answer is d) it encloses specific structures
