Column IColumn II(a) Operculum(i) Ctenophora(b) Parapodia(ii) Mollusca(c) Scales(iii) Porifera(d) Comb plates(iv) Reptilia(e) Radula(v) Annelida(f ) Hairs(vi) Cyclostomata and Chondrichthyes(g)...
14. Match the following:
read more
NCERT Exemplar
13. Segmentation in the body is first observed in which of the following:
(a) Platyhelminthes (b) Aschelminthes (c) Annelida (d) Arthropoda Solution: Form the four given options the correct answer is (c) Annelida
12. Could the number of eggs or young ones produced by an oviparous and viviparous mother be equal? Why?
Solution: No, the number of eggs or young produced by an oviparous and viviparous mother are not equal; the number of eggs produced by oviparous mothers is higher in comparison because fertilisation...
11. What are the modifications that are observed in birds that help them fly?
Solution: The following are some of the differences identified in birds that aid in flight: (i) Feathers are present. (ii) To aid flight, forelimbs are transformed into wings. (iii) Scales on the...
10. How important is the presence of air bladder in Pisces?
Solution: Air bladder in Pisces regulates Buoyancy which prevents fishes from sinking.
9. “All vertebrates are chordates but all chordates are not vertebrates”. Justify the statement.
SolutionThe phylum chordate is distinguished by the presence of Notocard and paired pharyngeal gill slits. Adults, on the other hand, replace the vertebrata notocard in the embryo in the subfilm...
8. Water vascular system is the characteristic of which group of the following:
(a) Porifera (b) Ctenophora (c) Echinodermata (d) Chordata Solution: From the four given options the correct answer is (c) Echinodermata This is a trait of theirs. A perforated panel known as...
7. What are the reasons that you can think of for the arthropods to constitute the largest group of the animal kingdom?
Solution: The causes of arthropods, which constitute up the largest group of animal kingdoms, are listed below. (i) They have jointed legs, which enable them to move about and perform a variety of...
Venation is a term for describing the pattern of arrangement of the
a. Floral organs b. Flower in inflorescence c. Veins and veinlets in a lamina d. All of the above Solution: Option (c) is the answer
Roots developed from parts of the plant other than radicle is called
a. Taproots b. Fibrous roots c. Adventitious roots d. Nodular roots Solution: Option (c) is the answer.
6. What are the peculiar features that you find in parasitic platyhelminthes?
Solution: The parasitic Platyhelminthes have the following characteristics: (i) Parasitic forms that live on their own. (ii) The observed bodily organisation is tissue organ grade. (iii)...
5. What is the difference between direct and indirect development?
Solution: Direct developmentIndirect developmentIt can be found in fish, reptiles, birds, and mammals.Occurs in in vertebrate amphibiansThe embryo develops into a fully developed human without going...
4. Distinguish between intracellular and extracellular digestion?
Solution: Intracellular digestionExtracellular digestionIt can be found in lower organismsOccurs in multicellular organismsOccurs within cellsOutside the cell, within the cavity of the ailmentry...
3. How useful is the study of the nature of body cavity and coelom in the classification of animals?
Solution: Coelomates are animals that have a coelom, which is a bodily cavity or fluid-filled area lined by the mesoderm. The mesoderm does not cover the body cavity in some animals; instead, the...
2. If you are given a specimen, what are the steps that you would follow to classify it?
Solution: The following are the steps to classify the specimen: (i) Determine the level of organisation: Determine how cells are organised at the cellular and tissue levels. (ii) Symmetry: Determine...
1. What are the difficulties that you would face in classification of animals, if common fundamental features are not taken into account?
Solution Animals are classed based on shared characteristics such as cell organisation, body symmetry, coelom type, digestive tract, circulation, and reproductive system. It is impossible to handle...
For taxonomic category of ‘family’ which of the following ‘suffixes’ used.
a. – Ae b. – Onae c. – Aceae d. – Ales Solution: Option (c) Aceae is the answer
How will the number of common characteristics change when we go from species to kingdom in a taxonomic hierarchy ?(a) Will decrease (b) Will increase (c) Remain same (d) May increase or decrease
Solution: Option (a) it decrease is the answer . As we go higher from species to realm, the quantity of normal attributes continues diminishing. Lower the taxa, more are the attributes that...
12. Describe the important characteristics of gymnosperms.
Solution: Gymnosperms have the following main characteristics: (i) The ovules of Gymnosperms are not contained by the ovary. They are exposed to the environment both before and after fertilisation....
11. Match the following (column I with column II)
Column IColumn II(a) Chlamydomonas(i) Moss(b) Cycas(ii) Pteridophyte(c) Selaginella(iii) Algae(d) Sphagnum(iv) Gymnosperm Solution: Column IColumn II(a) Chlamydomonas(iii) Algae(b) Cycas(iv)...
10. How would you distinguish monocots from dicots?
Solution: MonocotsDicotsHave single cotyledon seedSeeds having two cotyledonsFlowers are trimerousFlowers are tetramerous or pentamerousVenation in leaves is parallel.Have reticulate venations in...
9. Differentiate between the following:-
(i) red algae and brown algae (ii) liverworts and moss (iii) homosporous and heterosporous pteridophyte (iv) syngamy and triple fusion Solution: Following are the differences: i) 1. Chlorophyll a...
An inflorescence in which flowers are born laterally in acropetal succession, the position of the youngest floral bud in the floral axis of the plant shall be
a. Proximal b. Distal c. Intercalary d. Anywhere Solution: Option (b) is the answer.
Rearrange the following zones according to their position in the vertical section of a root area.
A. Root hair zone B. Zone of meristems C. Root cap zone D. Zone of maturation E. Zone of elongation Options: a. C, B, E, A, D b. A, B, C, D, E c. D, E, A, C, B d. E, D, C, B, A Solution: Option (a)...
8. Explain briefly the following terms with suitable examples:-
(i) protonema (ii) antheridium (iii) archegonium (iv) diplontic (v) sporophyll (vi) isogamy Solution: i) Protonema is the haploid stage of the bryophyte lifecycle, during which a thread-like chain...
7. What is heterospory? Briefly comment on its significance. Give two examples
Solution: Heterosporis refers to the production of two different types of spores in the same plant. Heterospory's significance: (i) In gymnosperms and angiosperms, Heterosporis stimulates seed...
6. Both gymnosperms and angiosperms bear seeds, then why are they classified separately?
Solution: The following are the explanations for the distinction between angiosperms and gymnosperms. (i) The ovules in gymnosperms are naked, but in angiosperms they are encased within the ovary....
5. Write a note on economic importance of algae and gymnosperms.
Solution: Importance of Gymnosperms (i) Gymnosperms are utilised as decorative plants. Some are bonsai trees that can be found in formal gardens. (ii) The fibres from these plants are used to make...
4. Mention the ploidy of the following:
protonemal cell of a moss; primary endosperm nucleus in dicot, leaf cell of a moss; prothallus cell of a fern; gemma cell in Marchantia; meristem cell of monocot, ovum of a liverwort, and zygote of...
3. Name three groups of plants that bear archegonia. Briefly describe the life cycle of any one of them.
Solution: Bryophytes, Pteridophytes, and Gymnosperms are the plants that bear archegonia. The life cycle of Bryophytes (i) Bryophytes produce gametes and are haploid. Bryophytes have multicellular...
2. When and where does reduction division take place in the life cycle of a liverwort, a moss, a fern, a gymnosperm and an angiosperm?
Solution: The reduction division takes place in the following stages: (i) Liverworts – In the sporangium, meiosis occurs in the spore mother cells, culminating in the generation of haploid spores....
1. What is the basis of classification of algae?
Solution: The presence of pigments that give algae its conventional colour is the primary criterion for categorization. Name of the pigmentColor impartedChlorophyll typeChlorophyceaeGreenChlorophyll...
Define the following as related to proteins (i) Primary structure (ii) Peptide linkage (iii) Denaturation.
(i) Primary structure When we discuss the primary structure of a protein, we refer to the exact sequence in which the amino acids are present. For example, the sequence of amino acid linkages in a...
What are essential and non-essential amino acids? Give two examples of each type.
Essential amino acids are those that are required by the human body but cannot be synthesized by the body. They must be obtained from an outside source, such as food. Consider the amino acids...
Distinguish anaphase of mitosis from anaphase I of meiosis.
Solution: The differences are as follows: Anaphase of mitosis Anaphase I of meiosis The chromatids divide and the centromere separates. Sister chromatids remain connected at their centromeres...
Describe the following:
(a) synapsis (b) bivalent (c) chiasmata
Draw a diagram to illustrate your answer.
Solution: a) Synapsis — During Zygotene of prophase-I of meiosis, homologous chromosomes link together. Synapsis is the term for this couple. b) A bivalent or tetrad is a pair of synapsed homologous...
Explain pressure flow hypothesis of translocation of sugars in plants.
Solution: In plants, food is constantly prepared in the form of glucose in the mesophyll cells of the leaves. The prepared meal is transformed to sucrose, which is then transported to the phloem's...
(a) With the help of well-labelled diagrams, describe the process of plasmolysis in plants, giving appropriate examples.
(b) Explain what will happen to a plant cell if it is kept in a solution having higher water potential.
Solution: If a plant is kept in a solution having higher water potential, the following are the things that can happen- a) When water leaves a plant's cell and the cell membrane, the cell shrinks...
What are the steps involved in the formation of a root nodule?
Solution: The following steps are involved in the formation of nodules: • Rhizobia colonize roots and attach themselves to epidermal and root hair cells. • Bacteria infect the root hair, causing it...
What are the conditions necessary for the fixation of atmospheric nitrogen by Rhizobium? What is their role in N2 -fixation?
Solution: For Rhizobium to fix nitrogen, the following conditions must be met. The production of root nodules requires a symbiotic connection between Rhizobium and roots.The requirement for a...
Analyse the events during every stage of cell cycle and notice how the following two parameters change
(i) number of chromosomes (N) per cell
(ii) amount of DNA content (C) per cell
Solution: Yes, DNA replication can occur throughout the G1 phase of the cell cycle. Each chromosome is made up of one chromatid, and the number of chromosomes remains constant. The chromosome is...
Can there be DNA replication without cell division?
Solution: Yes, DNA replication can occur without the need for cell division. DNA replication is required to prepare cells for cell division. Cell division is the next logical stage after cell...
Can there be mitosis without DNA replication in ‘S’ phase?
Solution: DNA synthesis or replication occurs during the S phase. For cell division to take place, DNA replication is required. Cell division is impossible without DNA replication.
Discuss with your teacher about
(i) haploid insects and lower plants where cell-division occurs.
(ii) some haploid cells in higher plants where cell-division does not occur.
Solution: (i)Honey bee drones are haploid insects that undergo cell division, and lower plants include Spirogyra, Chlamydomonas, and Pteridophytes. They create haploid gametes by mitosis rather than...
What is the significance of meiosis?
Solution: Significances of Meiosis: • It maintains the number of chromosomes in each species over generations. • Increases the genetic variation of an organism's population from generation to...
List the main differences between mitosis and meiosis.
Solution: The differences are as follows: MitosisMeiosisOccurs in somatic cellsOccurs in germ cellsThe number of chromosomes in the daughter cell is the same as in the parent cell.In comparison to...
Find examples where the four daughter cells from meiosis are equal in size and where they are found unequal in size.
Solution: Four daughter cells are generated during meiosis during the generation of male gametes (sperms) in human beings. During meiosis, the female gamete (ovum) divides into four daughter cells,...
How does cytokinesis in plant cells differ from that in animal cells?
Solution: Plant cytokinesisAnimals cytokinesisCell plate development causes this to happen.It occurs as a result of cleavage known as cell furrowing.The cell plate moves to the centre and expands...
Name the stage of cell cycle at which one of the following events occur:
(i) Chromosomes are moved to spindle equator.
(ii) Centromere splits and chromatids separate.
(iii) Pairing between homologous chromosomes takes place.
(iv) Crossing over between homologous chromosomes takes place.
Solution: (i)In Metaphase, chromosomes are transported to the spindle equator. ii) In Anaphase, centrosomes split and chromatids separate. iii) In meiosis, the pairing of homologous chromosomes...
Why is mitosis called equational division?
Solution: Since the number of chromosomes in the parent and progeny cells is the same, mitosis is known as equational division.
What is Go (quiescent phase) of cell cycle?
Solution: In mature animals, certain cells will not divide, and many others will divide only when it is necessary to replace cells that have been lost due to injury or cell death. These cells depart...
Describe the events taking place during interphase.
Solution: The following are the events that occur during interphase: • G1 phase (Gap 1) - The cell is metabolically active at this time. It develops and prepares DNA for replication. • S phase...
Distinguish cytokinesis from karyokinesis.
Solution: The difference between karyokinesis and cytokinesis is- CytokinesisKaryokinesisDuring the M phase of the cell cycle, the cytoplasm divides into two cells.The M phase of the cell cycle...
What is the average cell cycle span for a mammalian cell?
Solution: A mammalian cell's average cell cycle lasts 24 hours.
What causes the opening and closing of guard cells of stomata during transpiration?
Solution: The change in the turgidity of the guard cells is one of the factors that causes the stomata to open and close. The stomatal hole opens when guard cells become turgid, causing their thin...
Explain why xylem transport is unidirectional and phloem transport bi-directional.
Solution: When water is absorbed by roots through the xylem, it only travels upward. As a result, water transport is one-way. The phloem tissue transports the food. Food is created in the leaves and...
What essential role does the root endodermis play during mineral absorption in plants?
Solution: Endodermal cells have thickened radial walls as a result of lignin and suberin deposition. This blocks water and mineral apoplastic movement, enabling only symplastic mineral transport in...
Discuss the factors responsible for ascent of xylem sap in plants.
Solution: The following are the factors that cause xylem sap to rise in plants: Mutual attraction between water molecules is referred to as cohesion. Water molecules are drawn to the polar surface...
Describe transpiration pull model of water transport in plants. What are the factors influencing transpiration? How is it useful to plants?
Solution: The cohesion-tension model of water transport, which is formed by the loss of water or the process of transpiration from the pores of stomata of leaves, helps water rise in tall trees. The...
What role does root pressure play in water movement in plants?
Solution: Root pressure is developed in plant roots due to active nutrient absorption from the soil. Water (together with minerals) increases the pressure in the xylem when nutrients are actively...
How is the mycorrhizal association helpful in absorption of water and minerals in plants?
Solution: Mycorrhizal hyphae have a huge surface area, which aids in the absorption of water and minerals. As a result, plants' relationship with Mycorrhiza aids in the absorption of water and...
What happens when a pressure greater than the atmospheric pressure is applied to pure water or a solution?
Solution: When pure water or a solution is subjected to a pressure greater than atmospheric pressure, its water potential increases.
Briefly describe water potential. What are the factors affecting it?
Solution: The tendency of water to migrate from one location to another due to osmosis, gravity, and mechanical pressure is known as water potential. In other words, it is the difference between the...
Differentiate between the following:
(a) Diffusion and Osmosis
(b) Transpiration and Evaporation
(c) Osmotic Pressure and Osmotic Potential
(d) Imbibition and Diffusion
(e) Apoplast and Symplast pathways of movement of water in plants
(f) Guttation and Transpiration
Solution: The diffusion between all the following sets are- a) Diffusion and Osmosis DiffusionOsmosisIt is a form of passive transport in which a chemical moves from an area of higher concentration...
Explain why pure water has the maximum water potential.
Solution: Pure water has the greatest water potential since it has its own kinetic energy and is constantly in random motion. When solutes are added to pure water, the kinetic energy of the water...
Describe the role played by protein pumps during active transport in plants.
Solution: Protein pumps transport molecules through the cell membrane with the use of energy. These protein pumps transport the drug from a low-concentration area to a high-concentration area. They...
What are porins? What role do they play in diffusion?
Solution: Porins are proteins found in the outer membranes of plastids, mitochondria, and some bacteria that produce huge pores. Molecules as small as small proteins can pass through the huge holes....
What are the factors affecting the rate of diffusion?
Solution: Factors affecting the rate of diffusion are: Concentration gradient Permeability of the membrane separating them are all factors that influence the rate of diffusion. Temperature \s•...
Which of the following statements are true? If false, correct them:
(a) Boron deficiency leads to stout axis.
(b) Every mineral element that is present in a cell is needed by the cell.
(c) Nitrogen as a nutrient element is highly immobile in the plants.
(d) It is very easy to establish the essentiality of micronutrients because they are required only in trace quantities.
Solution: a) True b) False: Every mineral element found in a cell is not required by the cell. c) False- Nitrogen is a very mobile nutrient in plants. d) False- Since micronutrients are only...
How are the minerals absorbed by the plants?
Solution: The absorption process can be divided into two distinct phases. The first phase involves a passive uptake of ions into the apoplast, which is the cell's "free space" or "outside space."...
Why is it that in certain plants deficiency symptoms appear first in younger parts of the plant while in others they do so in mature organs?
Solution: The emergence of symptoms is determined by the mobility of a missing element. Symptoms develop in juvenile portions of the plant if the deficient element is relatively stationary, while...
If a plant shows a symptom which could develop due to deficiency of more than one nutrient, how would you find out experimentally, the real deficient mineral element?
Solution: Plants that show signs of numerous nutrient deficiencies are grown in distinct water culture settings. Sets 1 through 3 are given three different nutrients and are grown in hydroponics...
Name at least five different deficiency symptoms in plants. Describe them and correlate them with the concerned mineral deficiency.
Solution: Chlorosis is a loss of chlorophyll that causes the leaves to turn yellow. It is brought on by a lack of N, K, Mg, S, Fe, Mn, Zn, and Mo. Necrosis is the death of leaf tissue caused by a...
Explain with examples: macronutrients, micronutrients, beneficial nutrients, toxic elements and essential elements.
Solution: Macronutrients are nutrients found in plant tissues at concentrations of more than 10 mole kg-1 of dry matter. Plant growth necessitates a huge amount of them. Carbon, Hydrogen, Oxygen,...
Why is purification of water and nutrient salts so important in studies involving mineral nutrition using hydroponics?
Solution: Hydroponics is a way of growing plants without soil in a nutrient solution. Impure water has many contaminants in the form of soluble minerals that are dissolved in it. These contaminants...
‘All elements that are present in a plant need not be essential to its survival’. Comment
Solution: No, only around 17 of the 105 elements taken by plants are required for plant development and survival.
Organise a discussion in your class on the topic – Are viruses living or nonliving?
Solution: Characters who are non-living have the following features There isn't any cellular structure.Like crystals, they can be preserved in bottles.No energy storage or liberation systems...
Give a brief account of viruses with respect to their structure and nature of genetic material. Also, name four common viral diseases.
Solution: Viruses are infectious organisms that, when located outside the host cell, solidify in structure. The genetic material is either DNA or RNA (but never both), and it is found inside the...
What are the characteristic features of Euglenoids?
Solution: Eugenoids have the following characteristics: no cell wall.Their bodies are flexible due to a protein-rich coating known as a pellicle.There are two flagella of differing lengths. In...
Give a comparative account of the classes of Kingdom Fungi under the following:
(i) mode of nutrition (ii) mode of reproduction
Solution: Fungi are eukaryotic heterotrophic organisms. The kingdom fungus includes black dots on stale bread, yeast (which is used to make bread and beer), white spots on mustard leaves, and...
What do the terms phycobiont and mycobiont signify?
Solution: Fungi and algae form a symbiotic relationship in lichens. A phycobiont is a type of algae that is also seen in mycobiont fungi. Mycobiont provides structural protection for algae against...
Plants are autotrophic. Can you think of some plants that are partially heterotrophic?
Solution: These organisms are green and autotrophic, yet they hunt on and digest minute components for their nitrogen supply. Insectivores and carnivorous plants are somewhat heterotrophic....
State two economically important uses of:
(a) heterotrophic bacteria
(b) archaebacteria
Solution: The two economically important uses of- a) Vitamins, medicines, cheese, and curd are all made using heterotrophic bacteria. They aid in nitrogen fixation and the production of humus. b)...
21. Khadins, Bundhis, Ahars and Kattas are ancient structures that are examples for
(a) grain storage (b) wood storage (c) water harvesting (d) soil conservation Correct option – ( c ) Explanation - Khadins, Bundhis, Ahars and Kattas are all examples of water harvesting that...
What are micelles? Give an example of a micellar system.
Micelle is formed when soaps and detergents are dissolved in water. Micelle consists of hydrophobic and hydrophilic parts. When present in water, they form spherical formations with their...
9. Among the statements given below to select the ones that correctly describe the concept of sustainable development
(i) Planned growth with minimum damage to the environment (ii) Growth irrespective of the extent of damage caused to the environment (iii) Stopping all developmental work to conserve the environment...
Give four uses of emulsions.
Emulsions are used for a variety of purposes. Four uses of emulsions have been listed below: (i) The cleansing action of soap is determined by the formation of emulsions. (ii) The emulsification...
Describe briefly the four major groups of Protozoa.
Solution: The following are the four primary groups of Protozoa: Protozoa of the amoeboid class: They live in aquatic habitats and use pseudopodia to move and catch their prey. Flagellated...
How are viroids different from viruses?
Solution: The difference between viroids from viruses- (i) Viroids have single-stranded RNA without a protein coat, whereas viruses contain single-stranded or double-stranded RNA associated with a...
Find out what do the terms ‘algal bloom’ and ‘red-tides’ signify.
Solution: In contaminated water, algal blooms can be discovered. Algae overgrowth, particularly blue-green algae, causes them (cyanobacteria). Their expansion pollutes the water supply. They breathe...
What is the nature of cell walls in diatoms?
Solution: Cell walls of diatoms are unbreakable and embedded with silica, which imparts distinctive patterns to the walls. These diatoms deposit a lot of cell wall deposits in their habitat, which...
Discuss how classification systems have undergone several changes over a period of time.
Solution: The scientific classification was initially introduced by Aristotle. He classified plants into trees, shrubs, and herbs based on simple physical characteristics. He separated the animals...
Write the differences between multimolecular and macromolecular colloids. Give one example of each. How are associated colloids different from these colloids.
(I) The colloidal particles in multi-molecular colloids are an assemblage of atoms or tiny molecules having a diameter of less than 1 nm. The molecules in the aggregate are held together by Van der...
Discuss the trends in chemical reactivity of group 15 elements.
The general trends in chemical properties of the group – 15 are as follows:(i) Reactivity towards hydrogen:The elements present in group 15 undergo a reaction with hydrogen to form hydrides of type...
Why does the reactivity of nitrogen differ from phosphorus?
Nitrogen is a chemically less reactive element because of the high stability of its molecular form ${{N}_{2}}$. In nitrogen molecule, the two nitrogen atoms form a triple bond among themselves....
Discuss the general characteristics of Group 15 elements with reference to their electronic configuration, oxidation state, atomic size, ionisation enthalpy and electronegativity.
The general trend in group 15 elements is described as follows:(i) Oxidation states: The group 15 elements require 3 or more number of electrons to complete their octet and have 5 electrons in...
44. Answer the following :
(a) Name the endocrine gland associated with brain? (b) Which gland secretes digestive enzymes as well as hormones? (c) Name the endocrine gland associated with kidneys? (d) Which endocrine gland is...