31 Year NEET Previous Year Questions: The Living World- 1 - NEET MCQ

In the binomial nomenclature system proposed by Carolus Linnaeus, 'X' is the generic name, and 'Y' is the specific epithet, which together uniquely identify a species.

The house fly belongs to the Muscidae family, which is characterized by flies typically associated with humans and human habitations.

None of the options are matching with the language of the question.
The correct ascending order of taxonomic categories in case of animals is:
species → genus → family → order → class → phylum → kingdom  

Muscidae are commonly known as house flies or stable flies. These are found worldwide in distribution and contain almost 4,000 described species in over 100 genera.

• Anacardiaceae: It is famous as the cashew family or sumac family. Anacardiaceae include numerous genera, like cashew (in the type genus Anacardium), mango, poison ivy, poison oak.

• Hominidae: Hominidae family is one of the two living families of the ape superfamily Hominoidea. This family includes apes like orangutans (genus Pongo), the gorillas (Gorilla), and the chimpanzees as well as human beings (Homo).

• Poaceae: This family is a large and nearly ubiquitous family of monocotyledonous flowering plants known as grasses. This family includes the cereal grasses, bamboos, and the grasses of natural grassland.

Line in NCERT: "Housefly Musca Muscidae Diptera Insecta Arthropoda domestica"

Mangifera indica Linn.
When typed, scientific names follows the rules of Bionomial nomenclature. That is, the genus name should start with capital letter and the species name should be completely in small letters. When typed, these should be in italics. If written, they should be underlined separately.

Line in NCERT: "The scientific name of mango is written as Mangifera indica."

(A) Definition of biological species was given by Ernst Mayr. - This statement is correct. Ernst Mayr is indeed famous for his contributions to the biological species concept, which defines a species as a group of individuals that actually or potentially interbreed in nature.

(B) Photoperiod does not affect reproduction in plants. - This statement is incorrect. Photoperiod, or the length of day and night, significantly affects reproduction in many plants. It influences flowering time, which is a critical part of the reproductive process in plants.

(C) Binomial nomenclature system was given by R.H. Whittaker. - This statement is incorrect. The binomial nomenclature system was introduced by Carl Linnaeus, not R.H. Whittaker. R.H. Whittaker is known for proposing the five-kingdom classification system.

(D) In unicellular organisms, reproduction is synonymous with growth. - This statement is correct. In unicellular organisms, reproduction through cell division is essentially a form of growth, as one cell divides to become two, increasing the population size.

Therefore, the two correct statements are A (Definition of biological species was given by Ernst Mayr) and D (In unicellular organisms, reproduction is synonymous with growth), making the correct answer:  A and D

• Binomial nomenclature (also called binomial nomenclature or binary nomenclature) is a formal system of naming species of living things by giving each a name composed of two parts, both of which use Latin grammatical forms, although they can be based on words from other languages.

Line in NCERT: "Biological names are generally in Latin and written in italics."

• As we move from higher to lower rank of taxonomical hierarchy, common characters increase. Genus is the lowest common level of tomato and potato as both of them belong to genus 'Solanum'. It means they show all the common characters used to describe genus 'Solanum'.
• Thus, the correct answer is 'Genus.'

Line in NCERT: "Genus comprises a group of related species which has more characters in common in comparison to species of other genera. We can say that genera are aggregates of closely related species. For example, potato and brinjal are two different species but both belong to the genus Solanum."

The specific epithet for the species belonging to the genus Panthera is tigris. The complete scientific name for this species is Panthera tigris, commonly known as the tiger.

Line in NCERT: "Panthera has another specific epithet called tigris"

• In biology, a species is one of the basic units of biological classification and a taxonomic rank.
• A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring.
• While in many cases this definition is adequate, more precise or differing measures are often used, such as similarity of DNA, morphology or ecological niche.
• The presence of specific locally adapted traits may further subdivide species into subspecies.

Topic in NCERT: Taxonomic Categories

Line in NCERT: "All organisms, including those in the plant and animal kingdoms have species as the lowest category."

The correct hierarchy of classification of various taxons in descending order is given by:
Kingdom → Phylum → Class → Order → Family → Genus → Species

The kingdom is the highest taxon with the least similar characters shared between its various members while the species is the lowest level with almost similar morphological and behavioural similarities. Species is followed by Genus with slightly fewer similarities among its members.

• Species' is less general in following to genus. 
• Species are the smallest group among all the eight levels of taxonomy with almost similar characters.
• It is followed by Genus with slightly fewer similarities among its members.
• Examples: Armadillo – Dasypus novemcinctus, Cat – Felis catus, etc.

Hence, ‘species’ is the correct answer.

Line in NCERT: "Genus comprises a group of related species which has more characters in common in comparison to species of other genera."

• Biological classification is the scientific arrangement of organisms in a hierarchical series of groups and subgroups on the basis of similarities and differences in their traits.
• It helps in building evolutionary pathways and in identifying new organisms.
• The practical purpose of the classification of living organisms is to facilitate the identification of unknown organisms.
• It helps in building evolutionary pathways and in identifying new organisms.

Topic in NCERT: Classification

Line in NCERT: "Classification is the process by which anything is grouped into convenient categories based on some easily observable characters."