Answer: A
Explanation:
Oxygen makes up another 20 to 21 percent of our atmosphere. It's essential for life on Earth, and interestingly enough, it is poisonous when highly concentrated. Our concentration of 20 to 21 percent seems just right.
Explanation:
La siguiente entrada tiene como objetivo realizar una breve explicación sobre las moléculas biológicas lipídos y carbohidratos, las cuales son muy diversas ya que están formadas por carbono, lo cual hace que puedan formar muchos tipos de enlaces. Esta capacidad permite que las moléculas orgánicas adopten muchas formas complejas, como son las cadenas, las ramificaciones y los anillos.
Las moléculas biológicas son grandes polímeros que sintetizas para poder enlazarse con otras subunidades mucho mas pequeñas conocidos como monómeros. Las cadenas de subunidades estan unidas por enlaces covalentes los cuales se forman por deshidratación, estas cadenas pueden romperse por hidrólisis. La moléculas biologicas más importantes son los carbohidratos, lípidos, proteínas y ácidos nucleicos.
The answer is A
This is because 90% of energy is lost when we go up one trophic level. This means that even the the consumers tend to be larger in size, they are fewer in number and need to eat more in order to sustain themselves.
Water erosion is usually what people think of, but ice, wind and gravity can also cause erosion.
Water erosion is usually along rivers. As the water moves quickly by it rubs on the rock and dirt, causing rivers to slowly get wider.
Ice erosion is caused by glaciers. Sometimes it's a glacier rubbing against land, and there's a lake that was made by a glacier making it's way onto land and then melting.
Wind erosion is a big problem in fields and large open plains with loose dirt. The wind just blows all the dirt away.
Gravity can cause erosion and cliffs. Sometimes along a mountain or cliff the rock won't be able to hold itself up anymore, and gravity will pull it down.
Your answer would be all of them. Wind, water, ice, and gravity.
Answer:
The correct answer is d all of the above
Explanation:
There are many reasons behind increasing the concentration of atmospheric carbon dioxide such as
1 Burning of fossil fuels such as coal,petroleum increases the level of atmospheric carbon dioxide.
2 Increase in Argiculture also increases the level of green house gases such as CO2.
3 Clearing of lands for increasing population and agriculture by cutting down trees also adversely effect the normal 02:CO2 ratio in the atmosphere.