Classification and Biodiversity
Each subtopic includes About section, revision page link, 10 preview questions, and practice CTAs.
Characteristics of Living Organisms
SubtopicCharacteristics of Living Organisms under Classification and Biodiversity for Grade 9 IB.
Preview questions (no answers)
- 1.
Which of the following is an invertebrate with a soft body and often a shell?
A.Mollusk
B.Arthropod
C.Fish
D.Reptile
- 2.
Which vertebrate group has skin covered in hair or fur?
A.Birds
B.Reptiles
C.Mammals
D.Amphibians
- 3.
What do all living organisms have in common regarding their genetic material?
A.They all have the same number of chromosomes
B.They all use DNA as their genetic code
C.They all have a nucleus to store DNA
D.They all have circular DNA
- 4.
Which group of animals has segmented bodies and many pairs of legs, like centipedes?
A.Crustaceans
B.Insects
C.Myriapods
D.Arachnids
- 5.
What is the importance of having a universal binomial naming system?
A.It allows scientists from different countries to communicate about a species without confusion
B.It makes it easier to remember the names of all animals
C.It tells us exactly what the animal looks like
D.It categorizes animals based on their geographic location only
- 6.
Which characteristic is shared by both fish and amphibians?
A.They both have scales over their whole body
B.They are both endothermic
C.They both lay eggs in water
D.They both breathe through lungs throughout their entire life cycle
- 7.
Which life process provides the energy required for all other life processes?
A.Nutrition
B.Respiration
C.Excretion
D.Sensitivity
- 8.
Which statement correctly identifies the hierarchy of classification from the most general to the most specific?
A.Domain, Kingdom, Phylum, Class, Order, Family, Genus, Species
B.Species, Genus, Family, Order, Class, Phylum, Kingdom, Domain
C.Kingdom, Domain, Phylum, Order, Class, Family, Genus, Species
D.Phylum, Kingdom, Domain, Class, Order, Family, Genus, Species
- 9.
In the classification of animals, which of the following is a characteristic of all Chordates at some point in their life cycle?
A.A bony spinal column.
B.A notochord, a dorsal hollow nerve cord, and pharyngeal slits.
C.Warm-bloodedness and fur.
D.Lungs and a four-chambered heart.
- 10.
Which of the following best describes the characteristic of 'Sensitivity' in a unicellular organism like an Amoeba?
A.It has a brain that processes information from eyes.
B.It uses chemical receptors on its cell membrane to detect and move toward a food source (chemotaxis).
C.It does not show sensitivity because it is only one cell.
D.It only responds to light using a chloroplast.
Download the worksheet for Classification and Biodiversity - Characteristics of Living Organisms to practice offline. It includes additional chapter-level practice questions.
Five Kingdom and Linnaean Classification
SubtopicFive Kingdom and Linnaean Classification under Classification and Biodiversity for Grade 9 IB.
Preview questions (no answers)
- 1.
How many kingdoms are there in the classic Whittaker classification system?
A.3
B.4
C.5
D.6
- 2.
Which of the following represents a species name in binomial nomenclature?
A.Sapiens
B.Homo
C.Homo sapiens
D.Mammalia
- 3.
In the five-kingdom system, which kingdom is entirely composed of autotrophs?
A.Animalia
B.Fungi
C.Plantae
D.Protista
- 4.
The science of classification is important because it:
A.Creates confusion among scientists
B.Helps in identifying known and new species
C.Limits the number of species we study
D.Only focuses on animals
- 5.
A student is comparing the classification of a human () and a great white shark (). Based on the hierarchical structure provided in the diagram, at which taxonomic level do these two organisms first diverge into different groups?
A.Kingdom
B.Phylum
C.Class
D.Order
- 6.
Classification helps scientists understand the relationship between biodiversity and evolution. What is the study of evolutionary relationships called?
A.Phylogeny
B.Anatomy
C.Physiology
D.Ecology
- 7.
Which of the following represents the most general (largest) group in the Linnaean system shown below?
A.Phylum
B.Kingdom
C.Order
D.Class
- 8.
In a comparative genomics study, researchers find that Species 1 and Species 2 have a 2% difference in their mitochondrial DNA sequences, while Species 3 shows a 15% difference from both. If Species 1 and 2 are currently classified in the same Genus, how does the provided cladogram and molecular data inform the placement of Species 3 in the Linnaean hierarchy?
A.Species 3 belongs to the same Genus as 1 and 2, but represents the ancestral 'stem' species from which they evolved.
B.Species 3 is likely in a different Family or Order, as the significantly higher sequence divergence suggests a more distant common ancestor.
C.Species 3 must be in a different Domain, because a 15% sequence difference is the standard threshold for separating prokaryotes from eukaryotes.
D.Species 3 belongs to the same Species as Species 1, as DNA divergence of 15% is common between male and female members of the same population.
- 9.
A scientist isolates a unicellular organism from a deep-sea hydrothermal vent. Biochemical analysis reveals that the organism lacks a nuclear membrane, possesses histone proteins associated with its DNA, and has cell membranes containing branched hydrocarbons linked to glycerol by ether bonds. Based on the evolutionary relationships shown in the diagram, which classification is most accurate?
A.It belongs to Domain Archaea, as it shares key genetic and molecular features with Eukarya despite its prokaryotic cell structure.
B.It belongs to Kingdom Monera, because all unicellular organisms without a nucleus are genetically and biochemically identical.
C.It belongs to Domain Bacteria, because the absence of a nucleus and its existence in extreme environments are the primary traits of true bacteria.
D.It belongs to Kingdom Protista, because the presence of histones and introns indicates that it must be a eukaryotic organism.
- 10.
Which of the following is a characteristic of the Phylum Bryophyta?
A.They produce seeds in cones.
B.They have flowers for reproduction.
C.They lack true roots and have rhizoids instead.
D.They have a complex system of xylem and phloem.
Download the worksheet for Classification and Biodiversity - Five Kingdom and Linnaean Classification to practice offline. It includes additional chapter-level practice questions.
Homologous and Analogous Structures
SubtopicHomologous and Analogous Structures under Classification and Biodiversity for Grade 9 IB.
Preview questions (no answers)
- 1.
Which of these is the most modern way to check for homology?
A.Comparing fossil sizes
B.DNA sequencing
C.Looking at skin color
D.Measuring weight
- 2.
The scientific name of an organism consists of its:
A.Kingdom and Phylum
B.Genus and Species
C.Family and Order
D.Class and Genus
- 3.
If you are comparing the flipper of a seal and the wing of a penguin, they are considered:
A.Homologous because they are both forelimbs of vertebrates
B.Analogous because they are both used for swimming
C.Both A and B are correct depending on the context of comparison
D.Unrelated structures
- 4.
Which field of science focuses on naming and grouping organisms?
A.Taxonomy
B.Physiology
C.Geology
D.Astronomy
- 5.
An evolutionary biologist maps the limb development of three species as shown in the diagram. Based on their ancestry and the function of their limbs, which statement correctly classifies these structures?
A.The flippers of Species X and Species Z are homologous because they perform the same function for swimming.
B.The appendages of Species X and Species Y are homologous because they evolved from the same common ancestor.
C.The appendages of Species Y and Species Z are analogous because they share the same internal skeletal blueprint.
D.The structures of Species X and Species Y are analogous because they have diverged to serve different purposes.
- 6.
Which of the following statements about evolution is true?
A.Analogous structures prove that two species are closely related
B.Homologous structures are the result of convergent evolution
C.Vestigial structures have no evolutionary significance
D.Divergent evolution results in homologous structures
- 7.
What is the best way to distinguish between homologous and analogous structures in a lab setting?
A.By looking at the color of the structures
B.By measuring the size of the structures
C.By examining the internal anatomy and embryonic origin
D.By observing how the animal uses the structure in the wild
- 8.
If you compare the flipper of a seal and the flipper of a sea lion, and find they both evolved from a common walking ancestor but developed flippers independently, the flippers are:
A.Homologous as limbs, but analogous as flippers.
B.Analogous as limbs, but homologous as flippers.
C.Vestigial remnants of tails.
D.Exactly the same as fish fins.
- 9.
The ability of both bats and whales to use echolocation is an example of:
A.Homology, because both are mammals.
B.Convergent evolution of a complex functional trait (analogous behavior).
C.Divergent evolution from a common echolocating ancestor.
D.A vestigial trait in whales.
- 10.
Which of the following would provide the strongest evidence that a structure is vestigial?
A.It is very small in size.
B.It is found in only one species of a genus.
C.It has no apparent function but is homologous to a functional organ in a related species.
D.It is used for a different purpose than it was in the ancestor.
Download the worksheet for Classification and Biodiversity - Homologous and Analogous Structures to practice offline. It includes additional chapter-level practice questions.
Evolution and Natural Selection
SubtopicEvolution and Natural Selection under Classification and Biodiversity for Grade 9 IB.
Preview questions (no answers)
- 1.
How many domains are recognized in the current biological classification system?
A.Two
B.Three
C.Five
D.Six
- 2.
Which group of organisms lacks a cell wall?
A.Plants
B.Fungi
C.Animals
D.Bacteria
- 3.
Natural selection acts on the ______ of an organism.
A.Genotype only
B.Phenotype (observable traits)
C.Acquired characteristics
D.Name
- 4.
Which of the following is the most specific level of classification shared by a wolf () and a dog ()?
A.Species
B.Family
C.Genus
D.Order
- 5.
Which phylum of animals has a hollow dorsal nerve cord and a notochord during at least part of their development?
A.Arthropoda
B.Annelida
C.Chordata
D.Echinodermata
- 6.
Which of the following is NOT a source of genetic variation in a population of sexually reproducing organisms?
A.Independent assortment of chromosomes
B.Crossing over in Prophase I
C.Mitosis during tissue repair
D.Random fertilization of gametes
- 7.
According to the fossil record, in what general order did vertebrate groups appear on Earth?
A.Mammals --> Reptiles --> Amphibians --> Fish
B.Fish --> Amphibians --> Reptiles --> Mammals
C.Reptiles --> Fish --> Mammals --> Amphibians
D.Amphibians --> Reptiles --> Fish --> Mammals
- 8.
Which pair of taxa represents the most specific relationship between two organisms?
A.Two organisms in the same Phylum.
B.Two organisms in the same Class.
C.Two organisms in the same Family.
D.Two organisms in the same Genus.
- 9.
Which of the following is true regarding the use of cladograms?
A.They prove that one modern species evolved directly from another modern species.
B.They show the exact date and time when a species went extinct.
C.They illustrate the most probable pathway of evolutionary descent based on shared derived characteristics.
D.They are only useful for classifying organisms that are currently alive.
- 10.
How do mutations contribute to the process of natural selection?
A.They always make the organism stronger and faster.
B.They are the ultimate source of new alleles and genetic variation in a population.
C.They occur whenever an organism decides it needs a new trait to survive.
D.They prevent the population from evolving by keeping the DNA stable.
Download the worksheet for Classification and Biodiversity - Evolution and Natural Selection to practice offline. It includes additional chapter-level practice questions.