This post contains Important Questions from the Board of Secondary Education 2026 for Class 11th Biology. These important questions have also been asked in previous years’ exams. At the end of this post, you will also be able to solve objective-type self-tests useful for the 2026 exam.
MP BOARD 2026 – Class 11th Biology Important Questions & Answers
MP BOARD 2026- Objective Question Based Self Test – BIOLOGY Class 11th
Important Questions & Answers
Question 1: Why do organisms get classified?
Answer The purpose of biological classification is to organize the large number of known plants and animals into classes that provide names and facilitate study. Classifying organisms has the following benefits:
- It facilitates the study of the world’s myriad diverse organisms.
- It reveals the relationships between plants and animals.
- It makes it easier to identify organisms.
- It reveals the origin of organisms and their relationship to other organisms.
- It reveals the sequence and evidence of life’s evolution.
Question 2: Why do the classification systems of organisms change frequently?
Answer The primary reason for frequent changes in classification systems is biological evolution. Due to the ongoing evolutionary process in organisms, new species of plants and animals are added to the existing biological diversity. These new organisms are identified and assigned to the classification system. Due to evolution, species of plants and animals keep changing. Therefore, due to this, the prevailing classification system has to be changed and organisms have to be placed in their order.
Question 3: What is the difference between direct and indirect development?
Answer –Direct development: In this type of development, there is no larval stage. The zygote develops directly into an adult.
Examples: Humans, rats, elephants, and monkeys.
Indirect development: Some organisms develop through a larval stage. The zygote first transforms into a larva, and then the larva transforms into an adult. Examples: Echinodermata, Ascaris, cockroaches, etc.
Question 4: What do you understand by floral formula?
Answer– The formula by which the structure of a flower is expressed in a concise form is called a floral formula. In this formula or equation, the various structures and positions of the flower are expressed by different symbols.
Example – Mustard – EBr,O,K2+2,C4,A2+4,G(2)
Question 5: Why is mitosis called mitotic division?
Answer: Mitosis is called even division because at the end of division, two cells are formed that have the same number of chromosomes as the parent cell.
Question 6: What is the importance of meiosis?
Answer: Importance of meiosis:
- It keeps the chromosome number in cells the same from generation to generation.
- This division produces cells similar to the parent.
- Due to gene exchange during this division, it helps in the formation of new traits.
- This creates variation, which is essential for biological evolution.
- This causes one diploid cell to form four haploid cells.
Question 7: What effect does it have on the respiratory process of a mountain climber?
Answer: Atmospheric pressure increases when a person climbs higher. This forces outside air into the lungs, causing inhalation. Relaxation of the diaphragm and intercostal muscles returns the diaphragm and sternum to their normal positions and reduces thoracic volume. This decreases pulmonary volume. As a result, intrapulmonary pressure becomes slightly higher than atmospheric pressure. This causes air in the lungs to be expelled, resulting in exhalation.
Question 8: What do we learn from identifying individuals and populations?
Answer: Please write your own answers. (They will be uploaded to the site as soon as they become available.)
Question 9: Write the characteristics of fungi.
Answer: Please write your own answers. (They will be uploaded to the site as soon as they become available.)
Question 10: Write a note on the economic importance of gymnosperms.
Answer: Economic importance of gymnosperms:
- Gymnosperms hold the soil in place, thus preventing soil erosion.
- Gymnosperms are used as ornamental plants in gardens. Examples: Cycas, Thuja, Arocarya, etc.
- A type of starch is obtained from the stems of gymnosperms, which is used to make sago. The dried leaves and stems are used to make baskets, brooms, etc.
- Edible oil is obtained from various species of gymnosperms.
Question 11: How is the study of plant body useful to us?
Answer:
- Studying the morphology of living organisms reveals similarities or differences in their external shape, appearance, and color. However, many organisms may differ despite their external similarities.
- When we study the internal structure of plants or animals, we see differences in their cells, tissues, and organs.
- The study of the internal structure of plants is done under the anatomy branch of science. Studying the body reveals the physics, structure, and functions of plants. For example, the function of xylem and phloem tissues is to transport water and food.
Question 12: Write two functions each of parenchyma and collenchyma tissues.
Answer:
Two functions of parenchyma tissue:
- The primary function of parenchyma is to store and absorb food.
- It maintains the shape and stability of the plant.
Two functions of collenchyma tissue:
- It provides mechanical support to plants.
- When chloroplasts are present in it, it produces food.
Question 13: Define biogenesis.
Answer: The arrangement of ovules in the ovary is called nucellus. Marginal, parietal, basal, dorsal, and axial types of nucellus are found in plants.
Question 14: What is an enzyme? Explain.
Answer: Catalysts that catalyze chemical reactions occurring in the body of living organisms are called biocatalysts or enzymes. They can also act as catalysts outside the body. Chemically, all enzymes are globular proteins.
Question 15: Are the reactions of photosynthesis called “dark reactions”? Do they also require light? Explain.
Answer: Actually, the dark reactions of photosynthesis do not require darkness. However, the ATP and NADHP2 produced in the light reactions are used to reduce the CO2 produced in the dark reactions. ATP and NADHP2 are produced by chlorophyll in the presence of light.
Question 16: Write the difference between glycolysis and the Krobh’s cycle.
Answer:
| Glycolysis | Krebs Cycle |
| This process takes place in the cytoplasm. | This reaction occurs in the matrix of the mitochondria. |
| It occurs in both aerobic and anaerobic respiration. | It occurs only in aerobic respiration. |
| It is the first stage of respiration. | It is the third stage of respiration. |
| It is a linear pathway. | It is a cyclic pathway. |
| In this process, two molecules of pyruvic acid are formed from the breakdown of one glucose molecule. | In this reaction, the complete breakdown of acetyl-coenzyme A produces the inorganic substances CO2 and H2O. |
| In this process, 2 NADH2 and 2 ATP are produced from the breakdown of one glucose molecule. In this process, 2 NADH2 and 2 ATP are produced from the breakdown of one glucose molecule. | In this reaction, two molecules of acetyl-coenzyme A produce 6NADH2, 2FADH2, and 2ATP. |
| It is also called the Embden-Meyerhof-Parnas pathway or EMP pathway. | It is also called the citric acid cycle or tricarboxylic acid cycle or TCA cycle. |
Question 17: Explain the difference between activating and myosin muscle.
Answer
| Acting filaments | Myosin filaments |
| The light-colored band in striated muscle, called the ‘I’ band, is made of actin protein. | In striated muscle fibers, the darker section, called the ‘A’ band, is made of myosin protein. |
| During contraction, the ‘I’ band disappears, and the two ‘Z’ lines come closer. | During contraction, the ‘A’ band remains unchanged, but the ‘H’ region disappears. |
| A darker section or line is found in the middle of the ‘I’ band, called the ‘Z’ line. | A lighter section is found in the middle of the ‘A’ band, called the ‘H’ region. |
Question 18: Describe the important properties of enzymes.
Answer- Please write your own answers. (They will be uploaded to the site as soon as they become available.)
Question 19: How is respiration regulated?
Answer– Please write your own answers. (They will be uploaded to the site as soon as they become available.)
Question 20: Write the difference between taproot and adventitious root.
Answer
| Tap root | Adventitious Root |
| It arises from the radicle. | This arises from the plumule or shoot portion. |
| The primary root of a taproot never dies and persists throughout its life. | In this, the primary root formed from the radicle soon dies. In its place, numerous fibrous branches are found in the adventitious roots. |
| It extends very deep into the soil. In this, numerous branches emerge from the primary root. | These are found in the upper surface of the soil. The primary root is not found in the mature root system. It disappears. |
Question 21: Describe the exchange of enzymes like keto or orthoproducts.
Answer- Please write your own answers. (They will be uploaded to the site as soon as they become available.)
Question 22: Briefly describe why a cell is the basic unit of life.
Answer- Please write your own answers. (They will be uploaded to the site as soon as they become available.)
Question 23: Briefly describe:
(a) Arithmetic growth
(b) Geometric growth
Answer–
(a) Arithmetic Growth – In arithmetic growth, after mitotic cell division, only one daughter cell continues to divide while the other remains differentiated and matures. The simplest expression of arithmetic growth can be seen in the root elongating at a fixed rate.
(b) Geometric growth – In geometric growth, both daughter cells obtained from mitotic cell division divide. Due to limited nutrient supply, growth slows down and reaches a steady state.
Question 24: Write a note on the functions of the following hormones:
(a) Thyroid hormone
(b) Insulin and glucagon
Answer- Please write your own answers. (They will be uploaded to the site as soon as they become available.)
Question 25: Draw a diagram of a sarcomere of skeletal muscle and label the different parts.
Answer- Please write your own answers. (They will be uploaded to the site as soon as they become available.)
Question 26: What is a sinoauricular node (SAN)? Why is it called the heart’s pacemaker?
Answer: The sinoauricular node is located in the upper part of the right atrium of the heart. It is from here that the heart beats, and hence it is called the pacemaker of the heart. Sometimes, when the sinoauricular node does not function properly or stops functioning, the heart rate becomes irregular, slows, or stops. In the first two conditions, the heart is unable to pump blood throughout the body as needed. In such a situation, an artificial pacemaker is implanted, which functions similarly to the natural sinoauricular node and normalizes the heart rate.
Question 27: What is a junction? Describe the different types of junctions found in the human body.
Answer- Please write your own answers. (They will be uploaded to the site as soon as they become available.)
Question 28: What is the importance of abscisic hormone in plants?
Answer: Abscisic acid is a major plant hormone that has the following importance for plants. Therefore, due to these important properties, it is also called a stress hormone:
- It inhibits plant growth.
- It induces leaf senescence and defoliation.
- It blocks the effect of gibberellin, hence it is also called a gibberellin antagonist.
- It inhibits seed germination, allowing them to be preserved for a longer period.
Question 29: Define growth, differentiation, development and dedifferentiation, redifferentiation, limited growth, meristem, and growth rate.
Answer- Please write your own answers. (They will be uploaded to the site as soon as they become available.)
Question 30: Describe the structure of the human brain.
Answer- Please write your own answers. (They will be uploaded to the site as soon as they become available.)
Question 31: Draw a labeled diagram of a human nephron.
Answer- Please write your own answers. (They will be uploaded to the site as soon as they become available.)
Question 32: What are the distinctive features of euglenoids?
Answer– Characteristics of euglenoids:
- Most of them are found in fresh water. In place of a cell wall, they have a flexible membrane called a pellicle made of protein.
- They have two flagella, one small and the other large. They contain chlorophyll, so they make their own food in the presence of light. In the absence of light, they prey on microorganisms and feed on them. Example: Euglena.
Question 33: What are CAM plants? Write the characteristics of CAM plants.
Answer- Please write your own answers. (They will be uploaded to the site as soon as they become available.)
Question 34: Draw a comprehensive diagram of the Krebs cycle.
Answer- Please write your own answers. (They will be uploaded to the site as soon as they become available.)
Question 35: Explain the difference between a light reaction and a non-light reaction.
Answer–
| Photoreactivity | Non-photosynthetic reaction |
| This reaction requires light. | This does not require light. |
| Light is absorbed in this reaction. | There is no absorption of light in this reaction. |
| In this reaction, ATP and NADPH are produced. | In this reaction, ATP and NADPH are also produced, but in relatively small quantities. |
| This reaction occurs in the granular part of the chloroplast. | This reaction occurs outside the granular part. |
| There is no CO2 fixation in this reaction. | CO2 is fixed through this reaction. |
| In this reaction, water is dissolved and O2 is produced. | Neither water is dissolved nor O2 is produced. |
Question: Write the scientific name of mango.
Answer: The scientific name of mango is Mangifera indica.
Question: Define taxon.
Answer: A taxon is a group of organisms found at any level of the taxonomic hierarchy. Taxon is primarily based on similar life characteristics.
Question: How do viroids differ from viruses?
Answer:
Viruses –
- They are smaller than bacteria.
- They contain both DNA and RNA.
- They have a protein coat.
- They cause AIDS in humans.
Viroids –
- They are even smaller than viruses.
- They contain only RNA.
- They have a protein coat.
- They cause plant diseases such as spindle tuber disease in potatoes.
Question: Write the characteristics of fungi.
Answer: Characteristics:
- Fungi lack chlorophyll, so they are heterotrophic.
- Their anatomy is similar to that of a thallus, consisting of thread-
- like structures called hyphae.
- The cell wall is made of chitin or cellulose.
- Vascular tissue is absent.
Question: Write the characteristics of a ridge.
Answer- Please write your own answers. (They will be uploaded to the site as soon as they become available.)
Question: Write two important characteristics of algae.
Answer– Algae cells have cell walls made of cellulose. Food is stored in the form of starch.
Question: Briefly describe the following terminology with examples:
(a) Primordial filament
(b) Homogamous
(c) Antheridium
Answer: (a) First filament – This is the initial stage of the moss life cycle. The first filament is formed by seed germination. The first filament, or protonema, develops and becomes green, creeping, branched, and filamentous.
(b) Homogamous – The process of fusion of identical gametes is called isogamous. Example: Chlamydomonas.
(c) Antheridia – The male reproductive organ of Bryophytes and Pteridophytes is called an antheridium. The antheridium produces the double stamens.
Question: Describe the important characteristics of gymnosperms.
Answer- Please write your own answers. (They will be uploaded to the site as soon as they become available.)
Question: Name some parasites found on humans.
Answer: The following are parasites found on humans:
- Tinea solium
- Aceola hepatica
- Ascaris lumbricoides
- Wucherion bancrofti
- Encyclostoma
Question: Differentiate between a simple and a compound leaf.
Answer:
| Simple leaf | Compound leaf |
| The lamina is not completely divided. | The lamina are completely divided. |
| The axillary buds are found in the axil of a simple leaf. | The axillary buds are not found in the axil of the leaflets of a compound leaf. |
| The leaflets are usually arranged in an apical arrangement. | There is no saccular arrangement in the leaflets. |
| If stamens are present, they are attached to the base of the leaf. | The rachis is never found at the base of the leaflets. |
| The leaves fall off in autumn. | The rachis of a compound leaf falls off along with the leaflets during autumn. |
| The simple leaf has a joint and an internodes on the branch. | The leaflet of a compound leaf lacks branches, joints, and nodes. |
Question: Draw a labeled diagram of an animal cell.
Answer- Please write your own answers. (They will be uploaded to the site as soon as they become available.)
Question: Write five differences between oxic and anaerobic moments.
Answer- Please write your own answers. (They will be uploaded to the site as soon as they become available.)
Question: Describe the structure of the human excretory system with a diagram.
Answer- Please write your own answers. (They will be uploaded to the site as soon as they become available.)
You may also find this useful –
MP BOARD 2026- Objective Question Based Self Test – BIOLOGY Class 11
