Questions

Mitochondria is the Organelle in which Cellular Respiration Occur.

The left atrium is the upper left chamber of the heart that receives blood from the pulmonary veins.

The heart is responsible for circulating blood throughout the body. The heart is divided into four chambers. The upper chamber is known as the atrium while the lower chamber is referred to as the ventricle.

Data is organized in the form of row and columns, thus it is in tabular structure.

CHOICES (or) OPTIONS are what When you have three you have three, when you have two you have two, when you have one you have none. 

Most of the emissions of greenhouse gases (GHG) come primarily from burning fossil fuels (coal, hydrocarbon gas liquids, natural gas, and petroleum) for energy use and the major greenhouse gas is of course carbon dioxide (CO2) which comes from burning fossil fuels and land-use change.

But methane (CH4) and nitrous oxide (N2O), which mostly come from agriculture and waste, are also significant GHGs and shouldn't be discounted.