IB BIOLOGY: CLASSIFICATION KEY PRACTICE
EXAMINATION 2026 QUESTIONS WITH ANSWERS GRADED
A+
● What is the binomial system?. Answer: The binomial system of nomenclature is the
formal system by which all living species are classified (taxonomy). According to the binomial
system of nomenclature, every organism is designated a scientific name with two parts:
● How was the binomial system developed?. Answer: The binomial system of names for
species is universal
● What is the hierarchy of taxa?. Answer: The taxa form a hierarchy, as each taxon
includes
● What are taxa?. Answer: In biology, a taxon is a group of one or more populations of an
organism or organisms seen by taxonomists to form a unit.
● What are the three domains?. Answer: Most classification systems therefore now
recognize three major categories of organism, Eubacteria, Archaea and Eukaryotes.
● What are the features of bacteria?. Answer: - Histones associated with DNA: Absent
● What are the features of archaea?. Answer: - Histones associated with DNA: Proteins
similar to histones
● What are the features of eukaryota?. Answer: - Histones associated with DNA: present
● What are archaeans?. Answer: Archaea is a domain of single-celled organisms. These
microorganisms lack cell nuclei and are therefore prokaryotes.
● What are examples of archaeans?. Answer: Halophiles and methanogens
● What are the kingdoms of eukaryote?. Answer: Most biologists recognize four kingdoms
of eukaryote: plants, animals, fungi and protoctista
● What is natural classification?. Answer: Scientific consensus is to classify species in a
way
EXAMINATION 2026 QUESTIONS WITH ANSWERS GRADED
A+
● What is the binomial system?. Answer: The binomial system of nomenclature is the
formal system by which all living species are classified (taxonomy). According to the binomial
system of nomenclature, every organism is designated a scientific name with two parts:
● How was the binomial system developed?. Answer: The binomial system of names for
species is universal
● What is the hierarchy of taxa?. Answer: The taxa form a hierarchy, as each taxon
includes
● What are taxa?. Answer: In biology, a taxon is a group of one or more populations of an
organism or organisms seen by taxonomists to form a unit.
● What are the three domains?. Answer: Most classification systems therefore now
recognize three major categories of organism, Eubacteria, Archaea and Eukaryotes.
● What are the features of bacteria?. Answer: - Histones associated with DNA: Absent
● What are the features of archaea?. Answer: - Histones associated with DNA: Proteins
similar to histones
● What are the features of eukaryota?. Answer: - Histones associated with DNA: present
● What are archaeans?. Answer: Archaea is a domain of single-celled organisms. These
microorganisms lack cell nuclei and are therefore prokaryotes.
● What are examples of archaeans?. Answer: Halophiles and methanogens
● What are the kingdoms of eukaryote?. Answer: Most biologists recognize four kingdoms
of eukaryote: plants, animals, fungi and protoctista
● What is natural classification?. Answer: Scientific consensus is to classify species in a
way
