The scientific classification of Sunflower and Cereus includes the entire classification chart that includes kingdom, family, clade, tribe etc. A kingdom is the second highest taxonomic rank. A taxonomic rank is the level that a living organisms are placed in hierarchical level of arrangement of life forms. All the living organisms are divided into kingdoms. Plant kingdom is a main classification of living organisms that include all plants. There are six kingdoms which are: Plantae, Animalia, Fungi, Protista, Aschaea/Archaeabacteria and Bacteria Eubacteria. Sunflower and Cereus kingdom and all other plants kingdom is Plantaea.
Plant family is the group of plants which have something in common. Sunflower and Cereus family is a major factor of Sunflower and Cereus Scientific Classification. Plant family helps you narrow the search of your plants. It also gives you idea about, how the plant looks, how the seed will be like etc. These two plant families can be different or same. Sunflower belongs to the family Asteraceae and Cereus belongs to the family Cactaceae.
While comparing scientific classification, Sunflower and Cereus genus and other classification are also important. Also, when you compare Sunflower and Cereus, other factors should also be taken into considerations like order, subfamilies, tribe, clade etc. First plant's genus is Heilanthus and other plant's genus is Selenicereus. Sunflower tribe is Heliantheae and Cereus tribe is Hylocereeae. Sunflower clade is Not Available and order is Asterales whereas Cereus clade is Angiosperms, Core eudicots and Eudicots and order is Caryophyllales. Every plant have subfamilies. Sunflower subfamilies are, Helianthodeae and Cereus subfamilies are Cactoideae. In this way you can compare scientific classification of Sunflower and Cereus and other products also.