Hello friends! If you are preparing for the January- February B.Sc. Zoology examination 2026 and your MJC-1 paper is Diversity of Non-Chordates, this article is for you.

The syllabus is divided into four units. Today, we will cover Unit 1: Introduction to Non-Chordates. This unit includes the general features and classification (up to order) of ten phyla: Protozoa, Porifera, Cnidaria, Ctenophora, Platyhelminthes, Nemathelminthes, Annelida, Arthropoda, Mollusca, and Echinodermata.

In this article, I have provided the Top 20 Short Questions with Answers and Top 10 Important Long Questions to help you prepare for your examination.

This article is especially useful for B.Sc. Zoology students studying at Bihar universities, including Patna University, Patliputra University (PPU), Lalit Narayan Mithila University (LNMU), Babasaheb Bhimrao Ambedkar Bihar University (BRABU), Tilka Manjhi Bhagalpur University (TMBU), and Magadh University.

Since the four-year undergraduate programme was introduced in Bihar universities, many students have found it difficult to find MJC paper questions and study materials for each semester online. I created this resource to help students prepare for their examinations in one place.

Students can use these questions for practice and refer to their college notes or textbooks for detailed answers, diagrams, and definitions. I hope these study materials will help you prepare well and write your examination with confidence.

Top 20 Short Questions 

Q1. What are non-chordates?

Q2. What is the main difference between chordates and non-chordates?

Q3. What is the classification of animals?

Q4. What is Protozoa?

Q5. What are the main features of Porifera?

Q6. Why are sponges called pore-bearing animals?

Q7. What is Cnidaria?

Q8. What is Ctenophora?

Q9. What is Platyhelminthes?

Q10. What are Nemathelminthes?

Q11. What is Annelida?

Q12. What are the main features of Arthropoda?

Q13. Why is Arthropoda the largest animal phylum?

Q14. What is Mollusca?

Q15. What is Echinodermata?

Q16. What is the water vascular system?

Q17. What is a canal system in sponges?

Q18. What are spicules?

Q19. What is the difference between radial and bilateral symmetry?

Q20. What is the importance of animal classification?

Top 10 VVI Long Questions

Q1. Describe the general characteristics and classification of Protozoa, Porifera, Cnidaria, and Ctenophora.

Q2 Describe the general characteristics and classification of Platyhelminthes, Nemathelminthes, Annelida, Arthropoda, Mollusca, and Echinodermata.

Q3. Describe the general characteristics and classification of the phylum Protozoa with suitable examples.

Q4. Describe the general characteristics and classification of the phylum Porifera.

Q5. Describe the general characteristics and classification of the phylum Cnidaria.

Q6. Describe the general characteristics and classification of the phylum Ctenophora.

Q7. Describe the general characteristics and classification of the phylum Platyhelminthes.

Q8. Describe the general characteristics and classification of the phylum Nemathelminthes.

Q9. Describe the general characteristics and classification of the phylum Annelida.

Q10. Describe the general characteristics and classification of the phyla Arthropoda, Mollusca, and Echinodermata.

If you want to know what the B.Sc. Zoology Semester 1 MJC-1 examination paper looks like, you can check the Patna University previous year question paper using the link below. You can download the PDF for free and practise the questions.

👉 Download Free PDF: Patna University B.Sc. Zoology Semester 1 Question Paper

Do you want to prepare the answers to the Top 20 important short questions for B.Sc. Zoology Semester 1 MJC-1?

Get the Top 20 Short Questions with Answers PDF for only ₹29. It will help you practise important topics from the Diversity of Non-Chordates syllabus.

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Biochemistry is an important unit of the CSIR NET Life Science examination. It includes topics such as metabolic pathways, protein synthesis, histone modifications, the citric acid cycle, and fatty acid oxidation.

Here are five important questions based on the December 2024 Shift 1 question paper. These questions will help students revise important concepts .

Question 1: Glyoxylate Cycle

Which of the following statements about the glyoxylate cycle is INCORRECT?

(A) The glyoxylate cycle is absent in humans.

(B) The glyoxylate cycle occurs in special cell structures called glyoxysomes.

(C) This cycle helps organisms make sugars from fatty acids.

(D) This cycle involves enzymes present in both glyoxysomes and mitochondria.

Correct Answer: (D)

Solution and Explanation

The glyoxylate cycle is a modified form of the citric acid cycle (TCA cycle). It helps certain organisms convert the carbon present in acetyl-CoA into compounds that can be used to produce sugars.

This pathway is particularly important in plants, fungi, and many bacteria.

Let's understand the options:

Option (A): Correct. Humans do not have a functional glyoxylate cycle because they lack the key enzymes isocitrate lyase and malate synthase.

Option (B): Correct. In plants, the glyoxylate cycle takes place mainly in specialized organelles called glyoxysomes, particularly in germinating oil-rich seeds.

Option (C): Correct. The cycle helps plants convert carbon from stored fatty acids into compounds that can support sugar production.

Option (D): Incorrect The glyoxylate cycle in plants involves enzymes associated mainly with glyoxysomes and the cytosol, not both glyoxysomes and mitochondria as stated in the option.

Question 2: Protein Synthesis and Peptide Bond Formation

A newly discovered organism makes proteins in the reverse direction, from the C-terminal end to the N-terminal end. Which atom of the main protein chain would act as the nucleophile during peptide bond formation?

(A) Nitrogen of the amino group

(B) Carbon of the carboxyl group

(C) Oxygen of the carboxyl group

(D) Alpha-carbon (Cα)

Correct Answer: (C) Oxygen of the carboxyl group

Solution and Explanation

In normal protein synthesis, the ribosome adds new amino acids to the C-terminal end of a growing protein chain. Therefore, the protein is synthesized in the direction:

N-terminus → C-terminus

During normal peptide bond formation, the amino group of the incoming aminoacyl-tRNA attacks the carbonyl carbon of the peptidyl-tRNA. The amino group acts as the nucleophile.

However, the question describes a hypothetical organism that synthesizes proteins in the reverse direction.

If the reaction mechanism is reversed, the atom corresponding to the attacking nucleophile would be the oxygen of the carboxyl group.

Let's understand the options:

Option (A): Incorrect. The amino nitrogen acts as the nucleophile during normal peptide bond formation.

Option (B): Incorrect. The carbon of the carboxyl group acts as the electrophilic center during normal peptide bond formation.

Option (C): Correct according to the intended reverse-reaction interpretation. The carboxyl oxygen is the expected answer when the reaction is considered in reverse.

Option (D): Incorrect. The alpha-carbon is not the nucleophile responsible for peptide bond formation.

Question 3: Histone Modifications

Where do most histone modifications take place?

(A) N-terminal tail

(B) C-terminal tail

(C) Globular core

(D) Equally throughout the polypeptide chain. 

Correct Answer: (A) N-terminal tail

Solution and Explanation

Histones are proteins that help DNA remain organized inside the nucleus. DNA wraps around histone proteins to form a structure called the nucleosome.

Histone proteins can undergo chemical changes known as post-translational modifications (PTMs). These modifications influence how tightly DNA is packed and how genes are expressed.

Most commonly studied histone modifications occur on the flexible N-terminal tails of histones.

Examples include:

Acetylation: Addition of an acetyl group.

Methylation: Addition of a methyl group.

Phosphorylation: Addition of a phosphate group.

Ubiquitination: Addition of ubiquitin to a protein.

These modifications help regulate gene expression, DNA repair, and chromosome organization.

Let's understand the options:

Option (A): Correct. The N-terminal tails of histones are major sites of many histone modifications.

Option (B): Incorrect. The C-terminal region is not the main location for most commonly studied histone-tail modifications.

Option (C): Incorrect. The globular core also contains important modification sites, but it is not the principal answer to this question.

Option (D): Incorrect. Histone modifications do not occur equally throughout the entire polypeptide chain.

Question 4: Citric Acid Cycle (TCA Cycle)

The citric acid cycle mainly operates when oxygen is available. What is the main reason for this?

(A) Oxygen directly activates the enzymes of the TCA cycle.

(B) Oxygen acts as the final electron acceptor in the electron transport chain, allowing NADH to be converted back into NAD⁺.

(C) Oxygen removes toxic by-products of the TCA cycle.

(D) Oxygen directly activates ATP synthase.

Correct Answer: (B)

Solution and Explanation

The citric acid cycle, also called the TCA cycle or Krebs cycle, is an important metabolic pathway. It oxidizes acetyl-CoA and produces reduced coenzymes such as NADH and FADH₂.

These coenzymes carry high-energy electrons to the electron transport chain.

In aerobic respiration, oxygen acts as the final electron acceptor in the electron transport chain. It accepts electrons and combines with protons to form water.

This process allows NADH and FADH₂ to be oxidized back into NAD⁺ and FAD.

The regenerated NAD⁺ and FAD are needed for the TCA cycle to continue operating efficiently.

Let's understand the options:

Option (A): Incorrect. Oxygen does not directly activate the enzymes of the TCA cycle.

Option (B): Correct. Oxygen supports electron transport, allowing NADH to be reoxidized to NAD⁺.

Option (C): Incorrect. Removing toxic by-products is not the main reason the TCA cycle depends on aerobic respiration.

Option (D): Incorrect. Oxygen does not directly activate ATP synthase. ATP synthesis is driven by the proton gradient across the inner mitochondrial membrane.

Question 5: Beta-Oxidation of Fatty Acids

Which of the following statements about beta-oxidation of fatty acids is TRUE?

(A) It takes place in the intermembrane space of mitochondria.

(B) All reactions are the same for saturated and unsaturated fatty acids.

(C) It mainly takes place in the mitochondrial matrix for many fatty acids.

(D) It produces glucose directly as its main product.

Correct Answer: (C)

Solution and Explanation

Beta-oxidation is a metabolic pathway that breaks down fatty acids into smaller molecules of acetyl-CoA.

It is an important process for energy production, especially during fasting, prolonged exercise, and periods of low carbohydrate availability.

In eukaryotic cells, beta-oxidation of many fatty acids takes place mainly in the mitochondrial matrix. Very-long-chain fatty acids often begin their breakdown in peroxisomes.

During beta-oxidation, a fatty acid is shortened by two carbon atoms in each cycle.

Each cycle generally involves four steps:

1. Oxidation: FAD is reduced to FADH₂.

2. Hydration: Water is added to the intermediate.

3. Oxidation: NAD⁺ is reduced to NADH.

4. Thiolysis: Acetyl-CoA is released, and the fatty acyl chain becomes shorter.

Let's understand the options:

Option (A): Incorrect. The mitochondrial intermembrane space is not the main site of beta-oxidation.

Option (B): Incorrect. Unsaturated fatty acids may require additional enzymes, such as enoyl-CoA isomerase, and sometimes 2,4-dienoyl-CoA reductase.

Option (C): Correct. The mitochondrial matrix is the major site of beta-oxidation for many fatty acids.

Option (D): Incorrect. Beta-oxidation produces acetyl-CoA, NADH, and FADH₂. It does not directly produce glucose as its main product.

Read also : [CSIR NET Lifescience Full 14 Unit Syllabus ]

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Course: M.Sc. Botany Semester 1

Paper: MBOTCC-1

Topic: Phycology, Mycology and Bryology

Introduction

Botany is the branch of biology that deals with the scientific study of plants. It includes the study of different plant groups, their structure, reproduction, classification, evolution and economic importance.

Phycology, Mycology and Bryology are three important branches of botany. Phycology deals with algae, Mycology deals with fungi, and Bryology deals with bryophytes.

These groups are important for understanding plant diversity, the evolution of living organisms and their role in the environment. They are also useful in agriculture, medicine, food production and different industries.

Let us understand these three branches.

1. Phycology: Study of Algae

Definition of Phycology

Phycology is the branch of botany that deals with the scientific study of algae. It is also known as Algology.

Algae are simple, photosynthetic organisms commonly found in freshwater, marine water and moist places. They contain chlorophyll and prepare their food through photosynthesis.

Examples of algae include Chlamydomonas, Spirogyra, Chlorella, Volvox and Sargassum.

General Characteristics of Algae

The important characteristics of algae are given below.

1. Algae are simple organisms that may be unicellular, colonial or multicellular.

2. Most algae are found in aquatic environments, such as ponds, lakes, rivers and seas.

3. They contain photosynthetic pigments, including chlorophyll.

4. Their body is generally called a thallus because it is not differentiated into true roots, stems and leaves.

5. The cell wall is commonly made of cellulose, although its composition varies among different groups.

6. Algae may reproduce by vegetative, asexual and sexual methods.

7. They show great diversity in size, shape, structure and reproduction.

Types and Examples of Algae

Algae are classified into different groups based on their pigments, reserve food, cell wall composition, flagella and other characteristics.

Some important groups and examples are:

• Chlorophyta (green algae): Chlamydomonas, Spirogyra and Chlorella.

• Charophyta: Includes several groups of green algae closely related to     land plants.

• Xanthophyta (yellow-green algae): Vaucheria.

• Bacillariophyta (diatoms): Navicula and Pinnularia.

• Phaeophyta (brown algae): Sargassum and Laminaria.

• Rhodophyta (red algae): Polysiphonia and Gelidium.

These examples represent different forms of algal diversity.

Reproduction in Algae

Algae reproduce through three main methods.

1. Vegetative reproduction: It occurs through methods such as fragmentation. For example, Spirogyra commonly reproduces by fragmentation.

2. Asexual reproduction: It generally occurs through spores. In some algae, motile spores called zoospores are produced.

3. Sexual reproduction: It involves the fusion of gametes. Depending on the species, sexual reproduction may be isogamous, anisogamous or oogamous.

Economic Importance of Algae

Algae are important for both nature and human life.

They produce oxygen through photosynthesis.

They form the base of many aquatic food chains.

Some algae, such as Chlorella, are studied and used as sources of nutritional products.

Agar obtained from certain red algae is used in laboratories and food industries.

Alginates obtained from brown algae are used in food, pharmaceutical and other industries.

Some algae are used as food and animal feed.

Algae are also studied for their potential use in wastewater treatment and biofuel production.

Thus, phycology helps us understand algal diversity, their ecological role and their practical uses.

2. Mycology: Study of Fungi

Definition of Mycology

Mycology is the branch of biology that deals with the scientific study of fungi.

Fungi are eukaryotic organisms that obtain nutrients from organic matter. They do not contain chlorophyll and cannot prepare their own food through photosynthesis.

Examples of fungi include Rhizopus, Saccharomyces, Agaricus, Puccinia and Aspergillus.

General Characteristics of Fungi

The main characteristics of fungi are:

1. Fungi are eukaryotic organisms with a true nucleus.

2. They do not contain chlorophyll.

3. Their cell wall generally contains chitin and other substances.

4. Most fungi consist of thread-like structures called hyphae.

5. A network of hyphae is known as a mycelium.

6. Yeast is an example of a unicellular fungus.

7. Fungi may be saprotrophic, parasitic or symbiotic.

8. They reproduce through vegetative, asexual and sexual methods.

Types of Nutrition in Fungi

Fungi obtain their food in different ways.

1. Saprotrophic nutrition: Saprotrophic fungi obtain nutrients from dead and decaying organic matter. They help decompose dead organisms and recycle nutrients. Examples include many species of Rhizopus and Mucor.

2. Parasitic nutrition: Parasitic fungi obtain nutrients from living hosts and may cause diseases. For example, Puccinia causes rust disease in wheat.

3. Symbiotic nutrition: Some fungi live in close association with other organisms, with benefits to one or both partners. Lichens are formed by an association between a fungus and a photosynthetic partner, usually an alga or a cyanobacterium. Mycorrhizae are associations between fungi and plant roots.

Reproduction in Fungi

Fungi reproduce through different methods.

1. Vegetative reproduction: It may occur through fragmentation, budding or other methods. Yeast commonly reproduces by budding.

2. Asexual reproduction: Many fungi produce asexual spores. For example, Rhizopus can produce sporangiospores.

3. Sexual reproduction: It involves the fusion of compatible fungal cells or nuclei and may result in the formation of sexual spores.

Some fungi also show special phenomena such as heterothallism, heterokaryosis and the parasexual cycle. These processes are important in fungal genetics and evolution.

Economic Importance of Fungi

Fungi are useful in several fields.

Yeast (Saccharomyces cerevisiae) is used in baking and fermentation.

Some fungi are used in the production of antibiotics and other medicines.

Edible mushrooms, such as Agaricus, are used as food.

Fungi decompose organic matter and recycle nutrients.

Mycorrhizal fungi can help plants absorb water and minerals.

Some fungi are used as biological control agents against pests and plant pathogens.

However, some fungi cause diseases in plants, animals and humans. They may also spoil food and damage stored agricultural products.

Therefore, mycology is important in agriculture, medicine, biotechnology, food production and environmental studies.

3. Bryology: Study of Bryophytes

Definition of Bryology

Bryology is the branch of botany that deals with the scientific study of bryophytes.

Bryophytes are small, non-vascular land plants that commonly grow in moist and shady places. They include liverworts, mosses and hornworts.

Examples of bryophytes include Marchantia, Funaria, Sphagnum and Anthoceros.

Bryophytes are important for understanding the evolution of land plants and the adaptation of plants to terrestrial environments.

General Characteristics of Bryophytes

The main characteristics of bryophytes are:

1. They are generally small plants found in moist and shady habitats, although some species live in other environments.

2. They do not possess true vascular tissues like xylem and phloem.

3. Their plant body may be thalloid or leafy.

4. They do not have true roots. Instead, they possess structures called rhizoids that help in attachment.

5. The gametophyte is the dominant and independent stage of their life cycle.

6. The sporophyte remains attached to and nutritionally dependent, at least partly, on the gametophyte.

7. They reproduce through spores rather than seeds.

8. Water is generally required for the motile male gametes to reach the female reproductive structure.

Major Groups of Bryophytes

Bryophytes are commonly divided into three major groups.

1. Liverworts: Their plant body may be flat and thalloid or leafy. Marchantia is a common example. It may reproduce vegetatively through structures called gemmae.

2. Mosses: Mosses generally have small leafy shoots and rhizoids. Funaria and Sphagnum are common examples. Mosses often grow on moist soil, rocks and tree trunks.

3. Hornworts: Hornworts have a thalloid gametophyte and a characteristic elongated sporophyte. Anthoceros is a common example.

These groups differ in their morphology, anatomy, reproductive structures and sporophyte organization.

Reproduction in Bryophytes

Bryophytes reproduce through vegetative and sexual methods.

1. Vegetative reproduction: It may occur through fragmentation, gemmae and other structures. For example, Marchantia produces gemmae inside cup-like structures called gemma cups.

2. Sexual reproduction: The male reproductive organs are called antheridia, while the female reproductive organs are called archegonia. Antheridia produce male gametes, and archegonia contain the egg.

Water usually helps the motile male gametes reach the egg. After fertilization, the zygote develops into a sporophyte.

3. Spore formation: The sporophyte generally produces spores inside a capsule. Under suitable conditions, the spores germinate and develop into new gametophytes. In many mosses, the spore first develops into a protonema.

Life Cycle of Bryophytes

Bryophytes show alternation of generations, which means that their life cycle includes two multicellular stages.

The first stage is the gametophyte, which produces gametes. After fertilization, the zygote develops into the sporophyte. The sporophyte produces spores through meiosis. These spores germinate and develop into new gametophytes.

In bryophytes, the gametophyte is the dominant stage, while the sporophyte remains attached to it.

The evolution of the bryophyte sporophyte is an important topic in plant evolution. Researchers study changes in the foot, seta, capsule and spore-producing structures to understand the diversity of bryophytes.

Economic and Ecological Importance of Bryophytes

Bryophytes play several important roles in nature.

They help retain moisture in the environment.

They contribute to soil formation and help reduce soil erosion.

They provide suitable microhabitats for small organisms.

Some mosses can grow on bare surfaces and help in the early stages of ecological succession.

Sphagnum moss can hold large amounts of water.

Peat formed from partially decomposed plant material, often rich in Sphagnum, has been used as a fuel and in horticulture.

Bryophytes are studied as indicators of environmental conditions, including pollution in certain habitats.

Thus, bryology helps us understand the structure, reproduction, evolution and ecological importance of these simple land plants.

At zoobotanist.in, our aim is to make science education and exam guidance easy for every student. Study the basics, practice questions, and keep working towards your goal.

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