#1. The maintenance of an organism's internal environment within certain limits
#2, im not sure i completely understand the answer choices..
To keep in the stored enzymes so it can keep synthesizing at night, even when there is no sunlight. -- Stomata serve two main functions - they allow carbon dioxide to reach the cells in the leaf where the majority of photosynthesis takes place and they allow water to be transpired out off the leaf. During the day, stomata are generally open to allow photosynthesis to take place as quickly as possible. At night, when the lack of light means photosynthesis can't take place, many plants close their stomata to reduce water loss. There is one group of mainly desert plants, known as CAM plants, that keep their stomata closed during the day when water loss would be greatest, and open them at night, using a biochemical method to effectively store carbon dioxide in the leaf overnight.
An air mass is a large volume of air in the atmosphere that is mostly uniform in temperature and moisture. Air masses can extend thousands of kilometers across the surface of the Earth, and can reach from ground level to the stratosphere—16 kilometers (10 miles) into the atmosphere.
Air masses form over large surfaces with uniform temperatures and humidity, called source regions. Low wind speeds let air remain stationary long enough to take on the features of the source region, such as heat or cold. When winds move air masses, they carry their weather conditions from the source region to a new region. When the air mass reaches a new region, it might clash with another air mass that has a different temperature and humidity. This can create a severe storm.
Correct answer: B). They can be transformed into any type of body cell.
The stem cell is the biological cell that has the ability to differentiate into other types of cell. These are always found in the multi-cellular organism. These cells are known to be the foundation of every tissue and organ in our body. Embryonic stem cell is pluripotent, it means they can give rise to every type of cell in the body.
Example: Hematopoietic stem cells that give rise to all type of blood cells like red blood cells, white blood cells etc.
Hence, the correct answer would be option B.
D. Habitat fragmentation I believe