Which of the following makes ice cores so useful in determining the composition of the atmosphere in the past? A. the presence of pollenthe B. temperature of the core C. air bubbles D. fossilized plants

The correct answer is C: air bubbles.

Explanation:

Analysis of retained gases in ice, through perforations of over 2000 meters deep, has allowed determining the composition of the atmosphere in the past, knowing the CO² atmospheric concentrations and other gases involved in the greenhouse effect for at least 150,000 years. These concentrations have varied in the temporal scale of glaciation, showing low concentrations during glacial periods with low temperatures, and relatively high concentrations during interglacial periods with high temperatures. Between these two periods, abrupt variations on temperature and gas concentration are detected, meaning that changes in CO² cause changes in temperature.  

The increase in CO² is a highly important component in global climatic change and possibly the best documented. This information is the best paleoclimatic documents that complement with others such as marine sediments and tree rings, letting know about the principal traits of terrestrial weather in the lasts 420,000 years, practically four glacial-interglacial cycles.  

question#1

ans:

cell is the basic unit of organization of all living things. cells are often called the building block of life and it is the smallest unit of life. the study of cell is called cell biology. cell consists of cytoplasm enclosed within membrane, which contain bio-molecules such as proteins and nucleic acid.

two third of cell is water, which means that two-third of your whole body is water. the rest is the mixture of molecules, mainly proteins, lipids and carbohydrates.

question#2

ans:

organ:

an organ is a group of tissues specialized to form a functional unit. an example is the heart in animals.

organ system:

an organ system is a group of several organs whose functions are synchronized to release an effective action in a living organism. an example is digestive system.

question#3

different systems perform different function at tissue level. for example, the respiratory system facilitates breathing. in the alveoli tissue of the lungs, the exchange of oxygen and carbon dioxide molecules between the air and the bloodstream occurs by passive transport, so that oxygen is taken in and carbon dioxide and water are removed. different systems of the body carry out different functions. for example, your digestive system is responsible for taking in and processing food, while your respiratory system working with your circulatory system is responsible for taking up oxygen and getting rid of carbon dioxide.

question#4

different systems perform different function at tissue level. for example, the respiratory system facilitates breathing. in the alveoli tissue of the lungs, the exchange of oxygen and carbon dioxide molecules between the air and the bloodstream occurs by passive transport, so that oxygen is taken in and carbon dioxide and water are removed. different systems of the body carry out different functions. for example, your digestive system is responsible for taking in and processing food, while your respiratory system—working with your circulatory system is responsible for taking up oxygen and getting rid of carbon dioxide.

question#5

our body works because of the interactions that happen between organs and organ systems.  

for example:  

the heart to regulate blood flow throughout the body. the blood carries oxygen and nutrients to the cells and carries carbon dioxide and waste away from the cells. body systems work together in maintaining a constant internal environment. when this balance is disrupted, the body systems may not function properly, and human health can suffer.   you start to feel bad.

idk what happened..you tell