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  Nostoc are unicellular cyanobacteria. They contain a prokaryotic cell. They are autotrophic and perform photosynthesis. They are capable of nitrogen-fixing and form a symbiotic association with certain bryophytes. They contain differentiated cells known as heterocyst, which perform nitrogen fixation. 1. Find the correct statement (a)  Paramecium, Penicillium  and  Plasmodium  belong to the same kingdom (b)  Nostoc  and  Anabaena  come under Protista (c) lichen is a symbiotic association of an alga and Protozoan (d) Yeast is a fungus and is used in bread and beer production 2. Cyanobacteria are (a) oxygenic without nitrogenase (b) non-oxygenic without nitrogenase (c) oxygenic with nitrogenase (d) non-oxygenic with nitrogenase 3. Blue-green algae are included in (a) Prokaryotes (b) Protista (c) Fungi (d) Bryophytes 4. An organism that forms a symbiotic association with  Anthoceros (a)  Spirogyra (b)  Nostoc (c)  Ulothrix (...

  Chromoplast is a kind of plastid. It lacks chlorophyll and has carotenoids. They impart specific colours to fruits and flowers. They help in pollination and dispersal of seeds. 1. Which of the following plastid is found in ripe fruits? (a) chromoplast (b) chloroplast (c) leucoplast (d) amyloplast Answer: (a) 2. Anthocyanin pigments are (a) water-insoluble and located in chromoplasts (b) water-soluble and located in chloroplasts (c) water-soluble and located in vacuoles (d) water-insoluble and located in vacuoles Answer: (c) 3. Chloroplast does not contain (a) xanthophyll (b) anthocyanin (c) carotene (d) chlorophyll ‘b’ Answer: (b) 4. Which of the following pigment impart a red colour to tomato? (a) erythrocyanin (b) anthocyanin (c) 𝝱-carotene (d) lycopene Answer: (d) 5. Which of the following plastid doesn’t store food? (a) aleuroplasts (b) amyloplasts (c) chromoplasts (d) elaioplasts Answer: (c) 6. Protein storing plastid is (a) chromoplast (b) elaioplast (c) amyloplast (d) ale...

  Mitosis is essential for cell growth, repair and regeneration. Mitosis occurs during asexual reproduction and vegetative propagation. It gives rise to genetically identical cells having the same number of chromosomes as the parent cell. 1. DNA synthesis takes place during_________ phase (a) M phase (b) G 2  phase (c) G 1  phase (d) S phase Answer: (d) 2. Where does spindle fibres attach to during metaphase? (a) kinetochore of the chromosome (b) kinetosome of the chromosome (c) centromere of the chromosome (d) telomere of the chromosome Answer: (a) 3. Nucleolus and endoplasmic reticulum start disappearing at (a) late prophase (b) early prophase (c) late metaphase (d) early metaphase Answer: (b) 4. Early prophase of a diploid cell has_____ sets of chromosomes; telophase of a diploid cell has ____ sets of chromosomes (a) 1;2 (b) 2;1 (c) 2;2 (d) 1;1 Answer: (c) 5. A protein complex, that links sister chromatids, is (a) actin (b) cohesin (c) myosin (d) actomyosin Answer: (b)...

  Connective tissues support and connect different tissues and organs of the body. They originate from the mesoderm. Collagen or elastin fibres secreted by cells account for its flexibility, strength and elasticity. They perform a wide variety of functions depending on the nature of intercellular substances. Examples of connective tissue include adipose tissue, areolar tissue, bone, blood, cartilage, etc. 1. Find the correct statement (a) Areolar tissue is a loose connective tissue (b) Tendon is a specialized connective tissue (c) Cartilage is a loose connective tissue (d) Adipose tissue is a dense connective tissue 2. In comparison to human erythrocytes, frog’s erythrocytes are (a) smaller and fewer (b) nucleated and without haemoglobin (c) enucleated but with haemoglobin (d) nucleated and with haemoglobin 3. Tip of the nose and external ears have (a) areolar tissue (b) ligament (c) cartilage (d) bone 4. Mast cells contain (a) heparin and histamine (b) heparin and calcitonin (c) s...

  Plasmids are extrachromosomal DNA, mostly present in bacteria. They replicate autonomously. The size varies from a few base pairs to thousands bp. Many antibiotic resistance genes are present in plasmids. They are widely used in genetic engineering for manipulating and transferring genes. 1. Which of the following gene helps in identifying transformed cells? (a) plasmid (b) selectable marker (c) structural gene (d) vector 2. If the plasmid and the foreign DNA are cut by the same restriction endonuclease, recombinant DNA can be formed by joining both by (a) Polymerase III (b) EcoRI (c) Ligase (d) Taq polymerase 3. Find the incorrect statement about plasmids (a) they are circular (b) they replicate independently (c) they are transferrable (d) they are single stranded 4. The DNA molecule used for integrating foreign gene for cloning is called (a) vector (b) carrier (c) template (d) transformer 5. Which one of the following is correct for the plasmid pBR322 of E.coli.? (a) amp R ...

  The nucleolus is present in the nucleus of eukaryotic cells. Nucleoli are made up of DNA, RNA and protein. It is not a membrane-bound structure. It is the site of ribosomal RNA synthesis. Therefore, they are actively involved in protein synthesis. 1. Ribosomes are produced and assembled in (a) mitochondria (b) cytoplasm (c) nucleolus (d) Golgi apparatus 2. An outer membrane is not present in (a) lysosomes (b) mitochondria (c) plastid (d) nucleoli 3. Nucleoproteíns are synthesised in (a) cytoplasm (b) nucleoplasm (c) nuclear envelope (d) nucleolus 4. Which of the components of nucleolus disappears during late prophase and reappears during telophase? (a) Nucleolus (b) Nucleoplasm (c) Chromosomes (d) Nuclear pore 5. The main function of nucleolus is (a) Protein synthesis (b) ATP production (c) DNA synthesis (d) rRNA synthesis 6. Which of the following can pass through a nuclear pore? (a) Ribosomal subunits (b) Mitochondria (c) mRNA (d) both (a) and (c) 7. Which of the following are ...

  The cavity between the body wall and the gut wall is known as a true coelom. It is a characteristic feature of metazoans. Coelom has a mesodermal lining. Coelom is one of the differentiating features of different groups of animals. On the basis of formation, coelom is of two types; schizocoelom and enterocoelom. 1. Find the correct match (a) Molluscs – acoelomate (b) Platyhelminthes – coelomate (c) Aschelminthes – pseudocoelomate (d) Insects – pseudocoelomate 2. The fluid that comes out of earthworm while piercing it (without damaging its gut) is (a) slimy mucous (b) excretory fluid (c) hemolymph (d) coelomic fluid 3. Which of the following is not true about Annelida? (a) Ventral nerve cord (b) Closed circulatory system (c) Segmentation (d) Pseudocoelom 4. How platyhelminthes differ from annelids? (a) bilateral symmetry (b) pseudocoel (c) body cavity is absent (d) none of the above 5. Where does true coelom present in the body? (a) between mesoderm and endoderm (body wall) (b) be...