<span>In many plants, stomata are found only on
the lower surface of the leaf. The most likely explanation for this fact
is that water loss would be less on the shaded lower surface than in
direct sun. </span>
Living organisms in any biome interact through a variety of relationships. Organisms compete for food, water, and other resources. Predators hunt their prey. Some organisms coexist in mutually beneficial relationships (symbiosis), while others harm organisms for their own benefit (parasitism). Still others benefit from a relationship that neither helps nor harms the other organism (commensalism).
Animals found in the Arctic tundra include herbivorous mammals (lemmings, voles, caribou, arctic hares, and squirrels), carnivorous mammals (arctic foxes, wolves, and polar bears), fish (cod, flatfish, salmon, and trout), insects (mosquitoes, flies, moths, grasshoppers, and blackflies), and birds (ravens, snow buntings, falcons, loons, sandpipers, terns, and gulls). Reptiles and amphibians are absent because of the extremely cold temperatures. While many of the mammals have adaptations that enable them to survive the long cold winters and to breed and raise young quickly during the short summers, most birds and some mammals migrate south during the winter
Answer:
Dead or diseased trees can serve as a food source for some birds because there are some insects which feed on these dead trees and these insects are eaten by some birds. The body of insects is made of protein so it is a good food for birds. The insects which lived in the dead and diseased trees and feed on it are termites and bugs. Termites are also known as white ants. They feed on dead bodies of plants.
Answer:
A
Explanation:
Meiosis is the formation of non identical gametes
Answer:
A. If the aerobic pathway—cellular respiration—cannot meet the energy demand, then the anaerobic pathway—lactic acid fermentation—starts up, resulting in lactic acid buildup and "oxygen debt."
C. After about 90 seconds of intense exercise, the muscles become depleted of oxygen, and anaerobic respiration can no longer function to produce ATP, resulting in "oxygen debt."
Explanation:
There are two sources of carbohydrates in the human's body for energy (ATP) production. 1) Creatine phosphate and 2) Glycogen. Creatine phosphate metabolizes easily and yields ATP quickly. Whereas glycogen is stored form of carbohydrate which yields energy more slowly. Therefore, initially, our bodies use creatine phosphate and then shift to glycogen. Within 60-90 seconds, the creatinine phosphate in the body is mostly utilized and then energy is produced by the use of glycogen in aerobic pathway. During areobic pathway, oxygen supply is sufficient and per cycle, it produces 32 molecules of ATP. However, when oxygen supply is limited or absent, the body will metabolize glycogen to lactic acid via fermentation and produce only 2 molecules of ATP.
Now consider the example: Kenny hikes all day at a steady pace therefore the supply of oxygen is sufficient for aerobic cellular respiration for ATP production. In this scenario, the oxygen debt is minimal and Kenny relies on aerobic respiration pathway to obtain energy. On the other hand, Janelle runs fast (100 meters in 13.5 seconds) and her cellular respiration would be on the compense of aerobic pathway initially which will be shifted to anaerobic pathway after the supply of oxygen is reduced/minimum. Janelle will heavily rely on the anaerobic pathway because running fast needs energy which cannot be provided via aerobic pathway easily. Therefore, Janelle's body will produce lactic acid and suffer from oxygen debt.
