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All questions of The Study of Life for Grade 9 Exam

Can you explain the answer of this question below
One of the following functions is exhibited only by green plants and not by animals.
A: Growth
B: Photosynthesis
C: Digestion
D: Response
The answer is b.

Mira Joshi answered
  • Photosynthesis is a biochemical process of the synthesis of glucose using light energy. The process of photosynthesis occurs in chloroplast.
  • As only green plants have chloroplast hence photosynthesis can occur only in green parts of the plant.
Hence, the corret option is B i.e. Photosynthesis.

A binomial nomenclature has _________ words.
  • a)
    One
  • b)
    Five
  • c)
    Two
  • d)
    Three
Correct answer is option 'C'. Can you explain this answer?

Vivek Patel answered
The first word in a biological name represents the genus while the second word denotes the specific epithet.
Hence, the Correct Answer is C
NCERT Reference: 
Page no. 7 from chapter 1 of NCERT

Which among the following is not a code of nomenclature for organisms?
  • a)
    International Union of Pure and Applied Chemistry (IUPAC) 
  • b)
    International Code of Bacteriological Nomenclature (ICBN)
  • c)
    International Code of Zoological Nomenclature (ICZN)
  • d)
    International Code of Botanical Nomenclature (ICBN)
Correct answer is option 'A'. Can you explain this answer?

International Union of Pure and Applied Chemistry is for the nomenclature of organic compounds.
  1. International Code of Botanical Nomenclature (ICBN)
  2. International Code of Bacteriological Nomenclature (ICBN) and
  3. International Code of Zoological Nomenclature (ICZN)
These are the three codes of nomenclature for living organisms.

Which of the following is less general in characters as compared to genus?
  • a)
    Species
  • b)
    Family
  • c)
    Class
  • d)
    Division
Correct answer is option 'A'. Can you explain this answer?

Shilpa Bose answered
Less General than Genus: Species

Explanation:
- Genus is a taxonomic rank used in the biological classification of living and fossil organisms.
- It is a more general category than species, which is the basic unit of classification and the lowest taxonomic rank.
- Species is less general than genus because it refers to a specific group of organisms that share common characteristics and can interbreed to produce fertile offspring.
- Family, class, and division are all higher taxonomic ranks than species and therefore more general in nature.

Can you explain the answer of this question below:
The biologist who has been called the ‘Darwin of the 20th century’ is
A: Whittaker
B: Diener
C: Ernst Mayr
D: Linnaeus
The answer is c.

Preeti Khanna answered
  • Ernst Mayr was a German-born American who made decisive and groundbreaking contributions to avian taxonomy, evolution and population genetics.
  • Widely credited as the world's greatest evolutionary biologist in history, Mayr was fondly called the “Darwin of the 20th century”.
Hence, the correct option is C i.e. Ernst Mayr.

Solanum, Panthera, Homo are examples of:
  • a)
    Family
  • b)
    Division
  • c)
    Genera
  • d)
    Species epithet
Correct answer is option 'C'. Can you explain this answer?

Shalini Khanna answered
Genera

- Solanum, Panthera, Homo are examples of the scientific classification category called genera.
- Genera is a taxonomic rank used in the biological classification of living and fossil organisms.
- It is the second-lowest rank, just above species, in the hierarchical classification system.
- Genera are groups of closely related species that share a common ancestor and have similar physical characteristics, such as morphology, anatomy, and genetics.
- Each genus is given a unique name, which is written in italics and capitalized.
- The first letter of the genus name is always capitalized, while the species name is written in lowercase.
- The name of the genus is followed by the name of the species, which is called the species epithet or specific epithet.
- The combination of genus and species names is known as the binomial nomenclature, which is used to identify and distinguish each species from others.

Identify the incorrect statement:
  • a)
    Biological names are generally in Latin and written in italics. They are Latinised or derived from Latin irrespective of their origin.
  • b)
    The first word in a biological name represents the genus while the second component denotes the specific epithet.
  • c)
    Both the words in a biological name, when handwritten, are seperately underlined, or printed in italics to indicate their vernacular origin.
  • d)
    The first word denoting the genus starts with a capital letter while the specific epithet starts with a small letter.
Correct answer is option 'C'. Can you explain this answer?

Shreya Menon answered
Explanation:
In the context of biological names, statement 3 is incorrect. When handwritten, biological names are typically underlined, not separately, but as a whole to indicate their vernacular origin. When printed, biological names are usually written in italics. Underlining individual words in a biological name is not a standard practice.

The correct practice is to underline the entire biological name when handwritten or italicize it when printed.

Therefore, the correct answer is 3. Both the words in a biological name, when handwritten, are not separately underlined, or printed in italics to indicate their vernacular origin.

Which of the following statements regarding universal rules of nomenclature is incorrect?
  • a)
    The first word represents genus and the second word represents species
  • b)
    Biological names are generally in Greek
  • c)
    The biological names are printed in italics
  • d)
    Genus name starts with capital letter while species name starts with small letters
Correct answer is option 'B'. Can you explain this answer?

Arpita Saha answered
Introduction:
Universal rules of nomenclature are used to name living organisms. It helps to maintain a uniform and standard way of naming organisms. There are certain rules that need to be followed while naming an organism.

Incorrect statement:
The incorrect statement regarding universal rules of nomenclature is option 'B' - Biological names are generally in Greek.

Explanation:
Biological names are not generally in Greek. The biological names are formed using Latin words. Carl Linnaeus, a Swedish botanist, introduced the binomial nomenclature system. According to this system, a two-word name is given to each organism, which includes the genus and the species name.

Following are the correct statements regarding universal rules of nomenclature:

- The first word represents genus and the second word represents species.
- The biological names are printed in italics.
- Genus name starts with a capital letter while the species name starts with small letters.

Conclusion:
Therefore, the incorrect statement regarding universal rules of nomenclature is option 'B', as biological names are not generally in Greek.

Can you explain the answer of this question below:
The maintenance of constant temperature inside the body is an example of
A:Homoeostasis
B:Negative feedback loop
C:Both A and B
D:None of these
The answer is a.

Anjali Iyer answered
Homeostasis is how the body keeps conditions inside it the same. Scientists describe it as the maintenance of a constant internal environment. Two examples of things that the body keeps the same are: body temperature at 37degC.

In five kingdom system, the main basis of classification is
a)Structure of cell wall
b)Mode of Nutrition
c)Structure of nucleus
d)Asexual reproduction
Correct answer is 'B'. Can you explain this answer?

Rohit Shah answered
Among the five kingdom systems, the main, and the most basic form of classification is considered to be the classification according to the mode of nutrition. 

This classification is specified as ‘kingdom protista’ i.e. Monera, Protista, Fungi, Plantae and Animalia by R. H. Whittaker, who claimed that the simplest form of unicellular organisms depict both autotrophic and heterotrophic mode of nutrition.

The taxonomic hierarchy, from broadest to most specific, consists of the following categories:
  • a)
    Phylum, Class, Order, Family, Genus, Species
  • b)
    Kingdom, Order, Phylum, Genus, Family, Species
  • c)
    Kingdom, Phylum, Order, Family, Genus, Species
  • d)
    Class, Phylum, Kingdom, Family, Genus, Species
Correct answer is option 'C'. Can you explain this answer?

Poulomi Roy answered
Botanical gardens and zoological parks are places where people can go to observe and learn about different species of plants and animals. These places have a collection of different living species. Let's discuss the answer option by option:

a) Collection of endemic living species only:
- Endemic species are those that are native to a particular region or habitat.
- If a botanical garden or zoological park had a collection of only endemic species, it would mean that they only have plants and animals that are found naturally in that specific area.
- This would limit the diversity of the collection and make it less interesting for visitors.

b) Collection of exotic living species only:
- Exotic species are those that are not native to a particular region or habitat.
- If a botanical garden or zoological park had a collection of only exotic species, it would mean that they only have plants and animals that are not found naturally in that specific area.
- This may make the collection more interesting for visitors, but it would not showcase the biodiversity of the local area.

c) Collection of endemic and exotic living species:
- Having a collection of both endemic and exotic species allows for a greater diversity of plants and animals for visitors to observe and learn about.
- This also allows for a comparison between the local species and those from other regions, highlighting the uniqueness of each species.

d) Collection of only local plants and animals:
- Having a collection of only local plants and animals can be educational for visitors, as they can learn about the biodiversity of the local area.
- However, it may not be as interesting for visitors who are looking for a wider variety of plants and animals to observe and learn about.

In conclusion, the correct answer is option C, as having a collection of both endemic and exotic living species provides visitors with a diverse and interesting experience, while also highlighting the uniqueness of each species.

The book 'Systema Nature' was written by:
  • a)
    Linnaeus
  • b)
    Haeckel
  • c)
    Whittaker
  • d)
    Robert Brown
Correct answer is option 'A'. Can you explain this answer?

Swati Verma answered
  • The book ‘Systema Naturae’ was written by Carolus Linnaeus in 1735. The book marked the beginning of zoological nomenclature.
  • Carl Linnaeus is known as the “Father of Modern Taxonomy”.
  • In his book “Systema Naturae” (1735), he gave the hierarchical system of classification of the natural world into the plant kingdom, the animal kingdom and mineral kingdom. 

A group of interbreeding organisms is called a
  • a)
    Genus
  • b)
    Species
  • c)
    Family
  • d)
    Order
Correct answer is option 'B'. Can you explain this answer?

Nandini Patel answered
Species - A group of organisms that interbreed and produce fertile offspring. population - A group of organisms of the same species living in the same area at the same time, and which are capable of interbreeding. community - A group of populations living and interacting with each other in a common habitat.

In a hierarchical system of classification of plants, which of the following taxonomic rank ends in ‘aceae’?
  • a)
    Class
  • b)
    Order
  • c)
    Family
  • d)
    Genus
Correct answer is option 'C'. Can you explain this answer?

Gargi Ahuja answered
Species?

The taxonomic rank that ends in species is the lowest rank in the hierarchical system of classification of plants. It is called the "species" rank.

The scientific name of an organism is written in:
  • a)
    Italic or underlined letters
  • b)
    Capital letters
  • c)
    Bold letters
  • d)
    Small letters
Correct answer is option 'A'. Can you explain this answer?

Asha Chauhan answered
National Botanical Research Institute (NBRI) is situated at Lucknow.

Explanation:
National Botanical Research Institute (NBRI) is a research institute located in Lucknow, Uttar Pradesh. It was established in 1953 and is one of the premier institutions of the Council of Scientific and Industrial Research (CSIR). The institute is involved in research in the fields of plant sciences, biotechnology, and environmental biology. NBRI is also responsible for the conservation and documentation of India's plant wealth. It houses a herbarium with over one million plant specimens and a botanical garden with various plant species. Therefore, option A is the correct answer.

A taxon can be defined as _________
  • a)
    a group of related families
  • b)
    a taxonomic group of any ranking
  • c)
    a group of related species
  • d)
    the number and type of organisms present on Earth
Correct answer is option 'B'. Can you explain this answer?

Taxon is a term used in biological classification and refers to a taxonomic group of any ranking. It is used to classify living organisms into categories based on their characteristics, evolutionary history, and relationships to other organisms. Taxonomy is the science of naming, describing, and classifying organisms based on their characteristics and evolutionary relationships.

Types of Taxonomic Ranks

Taxonomic ranks are hierarchical levels of classification used to group organisms based on their characteristics, evolutionary history, and relationships to other organisms. The different types of taxonomic ranks are:

1. Domain
2. Kingdom
3. Phylum
4. Class
5. Order
6. Family
7. Genus
8. Species

Each rank is divided into smaller subcategories, providing a systematic framework for organizing and categorizing the diversity of life on Earth.

Importance of Taxonomy

Taxonomy is important because it helps scientists understand the diversity of life on Earth, how organisms are related to each other, and how they have evolved over time. It provides a way to organize and classify organisms into groups based on their characteristics and evolutionary relationships.

Taxonomy also helps scientists identify and name new species, and it provides a standardized system for communicating information about organisms. This is important for conservation efforts, as it allows researchers to identify and protect endangered species and ecosystems.

Conclusion

In conclusion, a taxon is a taxonomic group of any ranking used to classify living organisms based on their characteristics, evolutionary history, and relationships to other organisms. Taxonomy is an important field of study that provides a systematic framework for organizing and categorizing the diversity of life on Earth.

Select the correctly written scientific name of Mango which was first described by Carolus Linnaeus.
  • a)
    Mangifera indica
  • b)
    Mangifera indica
    Car. Linn.
  • c)
    Mangifera Indica
    Lin
  • d)
    Mangifera indica Linn
Correct answer is option 'D'. Can you explain this answer?

Naina Dey answered
Scientific Name of Mango

The correct scientific name of Mango which was first described by Carolus Linnaeus is "Mangifera indica Linn."

Explanation

- The scientific name of a species consists of two parts - the genus name and the specific epithet. The genus name always starts with a capital letter, while the specific epithet is written in lowercase.
- Carolus Linnaeus, also known as Carl Linnaeus, was a Swedish botanist who is known for his work in developing the modern system of naming organisms called binomial nomenclature.
- In 1753, Linnaeus described the Mango plant and gave it the scientific name Mangifera indica. The species name "indica" means "of India," which is where Mango is believed to have originated.
- The abbreviation "Linn." after the species name indicates that Linnaeus is the author who first described the species.
- The correct way to write the scientific name for Mango is "Mangifera indica Linn." with a period after the abbreviation for Linnaeus.

It is a handy book containing instructions of occurrence, collection and identification of species found in a particular area.
  • a)
    Key
  • b)
    Manual
  • c)
    Monograph
  • d)
    Flora
Correct answer is option 'B'. Can you explain this answer?

Megha Das answered
The correct answer is option 'B', which is a manual.

Explanation:
A manual is a book that contains instructions or information about a particular subject. In this case, the manual is a handy book that provides instructions for the occurrence, collection, and identification of species found in a particular area.

Key, Flora, and Monograph are also related to identifying species, but they have different meanings:

- A Key is a tool used to identify an unknown species by answering a series of yes or no questions.
- Flora is a comprehensive listing of all plant species found in a particular area.
- Monograph is a detailed written study of a particular group of organisms, often focusing on their taxonomy, distribution, and characteristics.

Therefore, the best answer for a book containing instructions for the occurrence, collection, and identification of species found in a particular area is a manual.

Binomial nomenclature was given by
A: Theophrastus
B: Linnaeus
C: R. H. Whittaker
D: Aristotle
The correct answer is b.
Can you explain this?

Vijay Bansal answered
Binomial Nomenclature was formly introduced by Swedish scientist Carl Linnaeus. In the binomial Nomenclature two terms are used to debote a species of living organisms, the first one indicate the genus and second one the specific epihet.Example:-Homo sapiens is the scientific name of human.

 The branch connected with nomenclature, identification and classification is
  • a)
    Ecology
  • b)
    Taxonomy
  • c)
    Physiology
  • d)
    Morphology
Correct answer is option 'B'. Can you explain this answer?

Anita Menon answered
Taxonomy is the practice of identifying different organisms, classifying them into categories and naming them.

So, the first step in taxonomy would be identification.

We would first identify the organisms, classify them, note down their characteristics and then give the scientific names.

So, the correct order would be-

-   Identification

-   Classification

-  Characterization

-  Nomenclature  

The Darwin of 20th century is:
  • a)
    Aristotle
  • b)
    Ernst Mayr
  • c)
    Carolus Linnaeus
  • d)
    Theophrastus
Correct answer is option 'B'. Can you explain this answer?

The Darwin of 20th century is Ernst Mayr.

Ernst Mayr was a German-American biologist and ornithologist who is considered as the "Darwin of 20th century" due to his significant contributions to the field of evolutionary biology. He was born in 1904 in Kempten, Germany and died in 2005 in Bedford, Massachusetts, United States.

Contributions to Evolutionary Biology:

1. Biological Species Concept: Mayr introduced the Biological Species Concept which defined a species as a group of individuals that can interbreed and produce viable offspring. This concept is widely accepted in the field of evolutionary biology.

2. Evolutionary Synthesis: Mayr played a crucial role in the development of the Evolutionary Synthesis, which was a unification of genetics and evolutionary biology. He proposed that the evolution of new species occurred due to the accumulation of genetic changes over time.

3. Geographic Speciation: Mayr proposed the theory of geographic speciation, which suggests that the formation of new species occurs when a population is geographically isolated from the parent population.

4. Ornithology: Mayr was also an accomplished ornithologist and contributed significantly to the study of bird species. He proposed the theory of allopatric speciation in birds, which suggests that the formation of new bird species occurs due to geographic isolation.

5. Systematics: Mayr made significant contributions to the field of systematics, which is the study of the classification of living organisms. He proposed the concept of "cladistics", which is a method of classification that groups organisms based on their evolutionary history.

Conclusion:

Ernst Mayr's contributions to the field of evolutionary biology have had a significant impact on our understanding of the process of evolution. His work has helped to shape the field of evolutionary biology and has influenced generations of biologists. Therefore, it is justified to consider him as the "Darwin of 20th century".

Full form of ICBN is:
  • a)
    International Code for Botanical Nomenclature
  • b)
    International Class for Botanical Nomenclature
  • c)
    Indian Code for Botanical Nomenclature
  • d)
    Indian Conduct of Biological Nomenclature
Correct answer is option 'A'. Can you explain this answer?

Pooja Desai answered
The full form of ICBN is the International Code for Botanical Nomenclature. It is the set of rules and recommendations for naming plants, algae, and fungi. The aim of the ICBN is to ensure that each organism has a unique and stable name that is recognized internationally.

History of ICBN:

- The first edition of the ICBN was published in 1906.
- It was revised several times, with the latest edition being the 2012 Vienna Code.
- The ICBN is maintained by the International Association for Plant Taxonomy (IAPT).

Rules of ICBN:

- The ICBN lays down rules for the formation and use of names for plants, algae, and fungi. It provides guidelines for naming new taxa, for the recognition of names that have already been published, and for the correction of errors.
- The ICBN also provides guidelines for the citation of names, for the use of ranks, and for the establishment of type specimens.
- It lays down rules for the use of diacritical marks, accents, and special characters in names.

Importance of ICBN:

- The ICBN is important because it provides a standardized system for naming plants, algae, and fungi.
- It ensures that each organism has a unique and stable name that is recognized internationally.
- The ICBN helps to avoid confusion and ambiguity in the naming of plants, algae, and fungi.
- It also helps to ensure that the names of plants, algae, and fungi are stable and do not change unnecessarily.

Conclusion:

The ICBN is an important set of rules and recommendations for naming plants, algae, and fungi. It provides a standardized system for naming these organisms, ensuring that each organism has a unique and stable name that is recognized internationally. The ICBN helps to avoid confusion and ambiguity in the naming of plants, algae, and fungi, and helps to ensure that the names of these organisms are stable and do not change unnecessarily.

One of the following functions is exhibited only by green plants and not by animals.
  • a)
    Growth
  • b)
    Photosynthesis
  • c)
    Digestion
  • d)
    Response
Correct answer is option 'B'. Can you explain this answer?

Om Desai answered
  • Photosynthesis is a biochemical process of the synthesis of glucose using light energy. The process of photosynthesis occurs in chloroplasts.
  • As only green plants have chloroplasts hence photosynthesis can occur only in green parts of the plant.
Hence, the corret option is B i.e. Photosynthesis.

The expansion of ICZN is:
  • a)
    Indian Code of Zoological Nomenclature
  • b)
    International Code of Zoological Nomenclature
  • c)
    Indian Class of Zoological Nomenclature
  • d)
    International Class of Zoological Nomenclature
Correct answer is option 'B'. Can you explain this answer?

Anushka Kumar answered
International Code of Zoological Nomenclature (ICZN) is the correct expansion.

Explanation:
The International Code of Zoological Nomenclature (ICZN) is a set of rules and guidelines established to regulate the use of scientific names for animals. It was first published in 1901 and has been updated several times to reflect changes in scientific knowledge and practices.

The ICZN is designed to ensure that each species has a unique, stable, and recognizable name that is widely accepted by the scientific community. It provides guidelines for the creation, spelling, and use of scientific names, as well as rules for resolving conflicts when different names are proposed for the same species.

The ICZN is maintained by the International Commission on Zoological Nomenclature (ICZN), which is responsible for interpreting and enforcing the rules of the code. The ICZN is recognized as the official code of nomenclature for animals by most countries and scientific organizations around the world.

In summary, the ICZN is an internationally recognized set of rules and guidelines for the naming of animals, designed to ensure that each species has a unique and stable name that is widely accepted by the scientific community.

 Homo sapiens belong to the genus ________
  • a)
    Hominidae
  • b)
     Mammalia
  • c)
    Homo
  • d)
     Sapiens
Correct answer is option 'C'. Can you explain this answer?

Lekshmi Roy answered
IUCN has identified 2700 species in Kew, Royal Botanical Garden as rare, threatened, and endangered. Let's understand this in detail.

IUCN:

IUCN stands for International Union for Conservation of Nature. It is a global organization that works towards the conservation of nature and biodiversity. IUCN assesses the conservation status of species around the world and publishes the Red List of Threatened Species. The Red List is a comprehensive database of species that are at risk of extinction.

Kew, Royal Botanical Garden:

Kew, Royal Botanical Garden is a world-famous botanical garden located in London, UK. It covers an area of 330 acres and is home to over 50,000 plant species.

Rare, Threatened, and Endangered Species:

Rare, threatened, and endangered species are those that are at risk of extinction. These species are facing various threats such as habitat loss, poaching, pollution, climate change, etc. IUCN assesses the conservation status of species and categorizes them into different categories based on their level of threat. The categories are:

1. Critically Endangered
2. Endangered
3. Vulnerable
4. Near Threatened
5. Least Concern
6. Data Deficient

2700 Species:

According to IUCN, there are 2700 species in Kew, Royal Botanical Garden that are rare, threatened, and endangered. This means that these species are facing a high risk of extinction if appropriate conservation measures are not taken.

Conclusion:

The conservation of rare, threatened, and endangered species is crucial for maintaining the balance of the ecosystem. Kew, Royal Botanical Garden plays a significant role in the conservation of these species. It is important to protect and conserve these species to ensure their survival for future generations.

The basic unit of classification is:
  • a)
    Species
  • b)
    Phylum
  • c)
    Genus
  • d)
    Family
Correct answer is option 'A'. Can you explain this answer?

Anshika Mishra answered
The Basic Unit of Classification:

The basic unit of classification is the species.

Explanation:

Species is the fundamental unit of classification in biology. It is defined as a group of individuals that can interbreed and produce fertile offspring.

Other taxonomic units such as genus, family, phylum, etc. are based on various characteristics of the organisms, but they all ultimately boil down to the species level.

Here are some of the reasons why species is considered the basic unit of classification:

1. Reproductive isolation: Members of the same species can interbreed and produce viable offspring, whereas members of different species cannot. This reproductive isolation is a crucial criterion for defining a species.

2. Evolutionary lineage: Species are also defined based on their evolutionary history and relationships. Organisms that share a common ancestor are grouped together into a species, and those that diverged earlier or later are classified into different species.

3. Practicality: The species level is also a practical unit of classification because it is often easier to identify and study individual organisms than larger groups.

In summary, the species is the basic unit of classification in biology because it represents a group of individuals that can interbreed and share a common evolutionary history.

Genus has
  • a)
    More common character possessing group of one species than other species
  • b)
    More common character possessing group of species than species of other genera
  • c)
    Less common character possessing group of species than other phyla
  • d)
    Less common character possessing group of one species than other species
Correct answer is option 'B'. Can you explain this answer?

Orion Classes answered
To understand the concept of genus in taxonomy:

- A genus typically comprises a group of species sharing more common characteristics among themselves than with species from other genera.
- This distinction helps in classifying organisms into related groups based on similarities in traits.
- Therefore, the correct answer is B: "More common character possessing group of species than species of other genera." This choice highlights the defining feature of a genus in taxonomy.

Which one of the following includes all the other lower taxa?
  • a)
    Class
  • b)
    Order
  • c)
    Genus
  • d)
    Species
Correct answer is option 'A'. Can you explain this answer?

Gaurav Kumar answered
The taxonomic ranks in descending order are domain, kingdom, phylum, class, order, family, genus and species. Higher taxon will comprise broader characteristic features and include features of its lower taxa. As a class would include order, family, genus and species.

The maintenance of constant temperature inside the body is an example of
  • a)
    Homoeostasis
  • b)
    Negative feedback loop
  • c)
    Both A and B
  • d)
    None of these
Correct answer is 'B'. Can you explain this answer?

Pallavi Chopra answered
Homeostasis maintains optimal conditions for enzyme action throughout the body, as well as all cell functions. It is the maintenance of a constant internal environment despite changes in internal and external conditions. In the human body, these include the control of blood glucose concentration.

Systematics includes
  • a)
    Identification
  • b)
    Taxonomy
  • c)
    Classification
  • d)
    All of the above
Correct answer is option 'D'. Can you explain this answer?

Preeti Iyer answered
Systematics is the study of the identification, taxonomy and nomenclature of organisms, including the classification of living things with regard to their natural relationships and the study of variation and the evolution of taxa. A major goal of biological classification systems is to reflect evolutionary relationships among organisms. Knowing phylogenetic relationships is essential for interpreting the evolution of traits of organisms.

One of the following functions is exhibited only by green plants and not by animals.
  • a)
    Growth
  • b)
    Photosynthesis
  • c)
    Digestion
  • d)
    Response
Correct answer is 'B'. Can you explain this answer?

Anjali Iyer answered
Photosynthesis takes place inside plant cells in small things called chloroplasts. Chloroplasts contain a green substance called chlorophyll. This absorbs the light energy needed to make photosynthesis happen.

In the chapter on ‘food’, the students are asked to discuss about people who do not get sufficient food to eat and how to avoid wastage of food. Which type of validity do you see in this type of content?
  • a)
    Process validity
  • b)
    Environmental validity
  • c)
    Content validity
  • d)
    Ethical validity
Correct answer is option 'D'. Can you explain this answer?

Sameer Kapoor answered
Explanation:

Ethical Validity:
- The focus on discussing people who do not get sufficient food to eat highlights the ethical aspect of the content. It encourages students to think about social responsibility and empathy towards those who are less fortunate.
- By addressing the issue of food wastage, the content also promotes ethical values such as sustainability and mindful consumption.
- Including such topics in the curriculum helps in instilling ethical values and a sense of responsibility towards the society in students.
In this context, the content demonstrates ethical validity as it aligns with the ethical principles of promoting social welfare and responsible behavior towards the environment and fellow human beings.

What is the significance of taxonomic categories and hierarchy in biology?
  • a)
    They represent concrete objects for classification
  • b)
    They denote biological entities solely based on morphology
  • c)
    They highlight the rank and grouping of organisms
  • d)
    They emphasize the number of legs an organism possesses
Correct answer is option 'C'. Can you explain this answer?

Top Rankers answered
Taxonomic categories and hierarchy in biology are crucial for organizing and classifying living organisms. They help in understanding the relationships between different species by grouping them based on shared characteristics. Each rank or taxon in the hierarchy represents a specific unit of classification, allowing scientists to categorize and study organisms more effectively. This system provides a structured way to classify the diversity of life on Earth, from broad categories like kingdoms to specific species, enabling scientists to make sense of the vast array of living organisms.

What is the primary purpose of the binomial system of nomenclature in biology?
  • a)
    To assign a common name to each organism
  • b)
    To identify organisms based on resemblances
  • c)
    To provide a scientific/biological name for each organism
  • d)
    To create a hierarchical system of classification
Correct answer is option 'C'. Can you explain this answer?

Understanding Binomial Nomenclature
The binomial system of nomenclature is a formal system of naming species that was developed by Carl Linnaeus in the 18th century. This system is essential in biology for several reasons.

Primary Purpose
- The primary purpose of the binomial nomenclature is to provide a **scientific/biological name for each organism**.

Key Features of Binomial Nomenclature
- **Two-Part Naming**: Each organism is given a two-part name — the genus name (capitalized) and the species name (not capitalized), such as *Homo sapiens* for humans.
- **Universality**: This system allows scientists worldwide to communicate about species without confusion, as common names can vary by region and language.
- **Clarity and Precision**: By using Latin or Greek roots for names, the binomial system reduces ambiguity. For example, *Canis lupus* clearly refers to the gray wolf, eliminating potential misunderstandings with other species.

Importance of Scientific Names
- **Identification**: Scientific names enable precise identification of organisms, which is crucial for research, conservation, and education.
- **Classification**: While the primary purpose is naming, the system also fits into a broader hierarchical classification, allowing scientists to categorize organisms into groups based on shared characteristics.

Conclusion
In summary, the binomial system of nomenclature serves as a crucial framework in biology, providing a standardized method to name and classify organisms, ensuring clear and effective communication within the scientific community.

What does the term "taxonomic category" refer to within the context of classification processes?
  • a)
    The final step in the classification hierarchy
  • b)
    A unit of classification representing a rank
  • c)
    The overall taxonomic arrangement
  • d)
    None of these
Correct answer is option 'B'. Can you explain this answer?

In the realm of classification, a "taxonomic category" specifically denotes a unit of classification that represents a particular rank. This term is commonly known as a "taxon." Each taxonomic category plays a crucial role in organizing organisms according to shared characteristics and evolutionary relationships. By assigning entities to specific taxonomic categories, scientists can create a structured hierarchy that aids in understanding the diversity of life on Earth.

Biological names are ……in ……. and written in ……….
  • a)
    Always, latin, italics
  • b)
    Generally, italics, latin
  • c)
    Generally, latin, italics
  • d)
    Always, italics, latin
Correct answer is option 'C'. Can you explain this answer?

Biological names are standardized in scientific nomenclature and are written in Latin for consistency and universal understanding. The correct answer is C: Generally, biological names are written in Latin and italicized. Here's why:

- Biological names are universally identified in Latin for consistency.
- Italicizing the names distinguishes them from regular text.
- This practice aids in clarity and consistency in scientific communication.

Biodiversity is:
  • a)
    Number and type of organisms present on earth.
  • b)
    Number and type of plants present on earth.
  • c)
    Number and type of animals present on earth.
  • d)
    None of the above.
Correct answer is option 'A'. Can you explain this answer?

Neha Sarkar answered
Understanding Biodiversity
Biodiversity refers to the variety of life on Earth, encompassing all living organisms, their genetic differences, and the ecosystems they form. Here’s a breakdown of why option 'A' is the correct answer:
1. Definition of Biodiversity
- Biodiversity is a comprehensive term that includes:
- The number of species (both plant and animal).
- The types of organisms present, including microorganisms, fungi, plants, and animals.
- The genetic diversity within these species.
2. Components of Biodiversity
- Biodiversity consists of three main components:
- Genetic Diversity: Variation within species, crucial for adaptation and survival.
- Species Diversity: The variety of species in a given area, including both flora and fauna.
- Ecosystem Diversity: The range of different habitats and ecological processes.
3. Importance of Biodiversity
- Biodiversity is vital for:
- Ecosystem Stability: More diverse ecosystems are more resilient and can better withstand environmental changes.
- Human Welfare: It provides resources like food, medicine, and raw materials.
- Cultural Value: Biodiversity contributes to cultural identity and recreational opportunities.
4. Why Not Options B and C?
- Options B and C narrow the definition to only plants or animals, missing the broader scope of all living organisms.
- Biodiversity includes microorganisms and fungi, which are equally important to ecosystems.
In summary, biodiversity encompasses the number and types of organisms present on Earth, making option 'A' the correct choice. Understanding this concept is crucial for conservation efforts and maintaining ecological balance.

Order…….. and primate comes under class……
  • a)
    Carnivora, mammalia
  • b)
    Diptera, Reptilia
  • c)
    Poals, Reptilia
  • d)
    Diptera, mammalia
Correct answer is option 'A'. Can you explain this answer?

Swati Iyer answered
Understanding the Classification of Animals
In biological classification, organisms are categorized into different hierarchical groups based on their evolutionary relationships. The two terms in question, "Order" and "Class," refer to specific levels in this taxonomy.
Order: Carnivora
- Carnivora is an order that includes a wide range of animals primarily characterized by their carnivorous diet.
- Members of this order include familiar animals like dogs, cats, bears, and seals. They possess adaptations such as sharp teeth and claws for hunting and consuming prey.
Class: Mammalia
- Mammalia is the class that encompasses all mammals, characterized by features such as hair or fur, mammary glands for nursing young, and a higher degree of brain development.
- Mammals are warm-blooded and usually give live birth, with some exceptions like monotremes (e.g., platypus).
Primate Classification
- Primates, which include humans, monkeys, and apes, are classified under the order Primates within the class Mammalia.
- This classification highlights their shared characteristics, such as flexible limbs, large brains, and social behavior.
Correct Answer Explanation
- The correct answer option 'A' states that "Order… and primate comes under class… Carnivora, Mammalia."
- This option is accurate because while Primates belong to the class Mammalia, Carnivora is another order within the same class. The confusion arises from the relationship between these classifications.
In conclusion, understanding the hierarchical structure of biological classification helps clarify how different organisms relate to one another within the animal kingdom.

The first step of the scientific method is
  • a)
    forming a hypothesis
  • b)
    making an observation
  • c)
    conducting an experiment
  • d)
    predicting the result of experiment
Correct answer is option 'B'. Can you explain this answer?

Hrithik Joshi answered
Observation as the First Step of the Scientific Method
Observation is the first step in the scientific method because it involves noticing and describing a phenomenon or event in the natural world. This initial step sets the stage for the entire scientific process by providing the foundation for forming a hypothesis, designing an experiment, and drawing conclusions based on evidence.

Key Points:
- Observations can be made using any of the five senses or through the use of instruments and tools.
- Observations should be objective and based on factual information rather than personal opinions or bias.
- The more detailed and accurate the observations, the better the subsequent steps of the scientific method can be carried out.

Example:
For example, a scientist observing the behavior of a particular species of bird may notice that the birds tend to gather in groups during certain times of the day. This observation can then lead to the formulation of a hypothesis, such as "Birds gather in groups to protect themselves from predators."
By beginning with observation, scientists can gather data, identify patterns, and ultimately develop testable hypotheses that can be further explored through experimentation.

Assertion (A): Taxonomy is crucial for identifying and classifying the vast diversity of living organisms.
Reason (R): The scientific names of organisms are always derived from Latin and consist of two parts.
  • a)
    If both Assertion and Reason are true and Reason is the correct explanation of Assertion
  • b)
    If both Assertion and Reason are true but Reason is not the correct explanation of Assertion
  • c)
    If Assertion is true but Reason is false
  • d)
    If both Assertion and Reason are false
Correct answer is option 'C'. Can you explain this answer?

The assertion is true because taxonomy is essential for identifying and classifying the vast diversity of living organisms. However, the reason is false because scientific names are generally Latin or Latinised, not always strictly derived from Latin. The names can originate from other languages and are modified to fit Latin grammar. Therefore, the correct answer is that the assertion is true but the reason is false.
Topic in NCERT: Diversity in the Living World
Line in NCERT: Biological names are generally in Latin and written in italics. They are Latinised or derived from Latin irrespective of their origin.

Which classification correctly matches the organism "Wheat" with its respective Class and Order?
  • a)
    Class - Monocotyledonae, Order - Poales
  • b)
    Class - Dicotyledonae, Order - Sapindales
  • c)
    Class - Insecta, Order - Diptera
  • d)
    Class - Mammalia, Order - Primata
Correct answer is option 'A'. Can you explain this answer?

Lead Academy answered
Wheat, scientifically grouped under the genus Triticum, falls within the Class Monocotyledonae and the Order Poales. Option A is the correct answer as it accurately matches wheat with its taxonomic classification in terms of class and order.

What is incorrect for taxonomic hierarchy?
  • a)
    There are 7 obligate and more than 21 intermediate categories
  • b)
    Higher the category, fewer the number of organisms
  • c)
    Lower the category, more the number of common features
  • d)
    Greatest similarity in structure is found in between members of a species
Correct answer is option 'A'. Can you explain this answer?

Top Rankers answered
The taxonomic hierarchy generally includes 8 primary categories (kingdom, phylum, class, order, family, genus, species, variety) and not 7 obligate categories.
The other statements are correct, based on the classification system used in biology.

A group of closely related classes is called:
  • a)
    Genus 
  • b)
    Phylum
  • c)
    Order
  • d)
    None
Correct answer is option 'B'. Can you explain this answer?

  • Phylum is one of the major taxonomic ranks, and it represents a high-level grouping of organisms that share certain fundamental characteristics.
  • Within a phylum, organisms are further divided into classes, which are more specific and share even more closely related characteristics.
Correct answer is B.
NCERT Reference: 
Topic - Taxonomy from chapter "The Living world" of NCERT.
Topic in NCERT: Phylum
Line in NCERT: "Classes comprising animals like fishes, amphibians, reptiles, birds along with mammals constitute the next higher category called Phylum."

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