Plant and animal cells. Cytoplasm. Jelly-like substance, where chemical reactions happen. In plant cells there's a thin lining, whereas in animal cells most of the cell is cytoplasm. Plant and animal cells. Nucleus. Controls what happens inside the cell.Carries genetic information. In exams don't call the nucleus the 'brain' of the cell.ytoplasm. Jelly-like substance, where chemical reactions happen. In plant cells there's a thin lining, whereas in animal cells most of the cell is cytoplasm. Plant and animal cells. Nucleus. Controls what happens inside the cell. Carries genetic information. In exams don't call the nucleus the 'brain' of the cell.
Iron is rarely found in its pure form on the surface of the earth; as it tends to get oxidized when it comes in contact with atmospheric oxygen. For this reason, most of its ores are in the form of iron oxides.
Forms of Iron. Iron comes in 2 forms: heme iron (from meat and animal products) and non-heme iron (from other sources like vegetables and iron supplements). Non-heme iron used in iron supplements can appear in 3 forms:1  Ferric ironâThis type of iron is less soluble than ferrous iron when the acidity in the stomach is low. 2  It has to be converted to ferrous iron (Fe 2+) so that it can be dissolved and absorbed in the small intestine.ron comes in 2 forms: heme iron (from meat and animal products) and non-heme iron (from other sources like vegetables and iron supplements). Non-heme iron used in iron supplements can appear in 3 forms: