Questions

A greenhouse gas (GHG) is any gas in the atmosphere that absorbs and emits radiation in the thermal infrared range.

The increase in average global temperatures that results from an enhanced greenhouse effect.

Effects of increased greenhouse gas emissions:

Increases in the different greenhouse gases have other effects apart from global warming including ocean acidification, smog pollution, ozone depletion as well as changes to plant growth and nutrition levels.

Iran is an important oil-producing region in the Middle East. Abadan on the Abadan island has one of the largest refineries in the world. 

The letter 'B' sounding resembles same as the bird 'Bee'. 

Hence, alphabet 'B' is a bird.

Magma is injected into surrounding rock forming an igneous intrusive.

Actually it is a plutonic formation in which magma present beneath Earth surface deforms the shape of rocks present above it
 

During most of the cell cycle, interphase, the chromosomes are somewhat less condensed and are not visible as individual objects under the light microscope. However during cell division, mitosis, the chromosomes become highly condensed and are then visible as dark distinct bodies within the nuclei of cells. The chromosomes are most easily seen and identified at the metaphase stage of cell division and most of the chromosome images in this gallery are pictures of metaphase chromomosomes.

The cell division takes place in mitosis stage.