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Pleomorphism of Lysosomes

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  Pleomorphism of Lysosomes Lysosomes show pleomorphism, which means they occur in many different forms according to their functional state. They are not always identical in shape, size, or contents. Their appearance changes depending on whether they are newly formed, involved in digestion, or storing undigested waste materials.  Lysosomes are membrane-bound organelles containing hydrolytic enzymes. These enzymes digest proteins, lipids, carbohydrates, nucleic acids, and other cellular materials. Since lysosomes perform different digestive functions inside the cell, they appear in different structural forms. This property is called pleomorphism.  The main pleomorphic forms of lysosomes are primary lysosomes, secondary lysosomes, autophagic vacuoles, and residual bodies. Primary lysosomes are newly formed lysosomes produced by the Golgi apparatus. They contain inactive hydrolytic enzymes and have not yet taken part in digestion. They are small, spherical vesicles surround...
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Biological Science Practice SET

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  1. Evolutionary homology is similarity due to common ancestry. Which of the following characters are evolutionary homologies? a) wing of a bird and a bat b) beak of a vulture and an eagle c) fin of a fish and a whale d) webbed feet of a duck and a frog   2. Locus   A in a diploid   organism has two alleles A 1 and A 2 , where A1 is dominant over A 2 . Additionally A 2   is deleterious in the homozygous condition. Allele A 2 takes a long time to get eliminated from the population because a) A 1 is harbored in the heterozygotes b) A 1 is harbored in the homozygotes c) A 2 is harbored in the heterozygotes d) A 2 is harbored in the homozygotes   3. In a population of 100 diploid individuals, the frequency of neutral alleles A 1 and A 2 are 0.4 and 0.6 respectively. Assuming Hardy-Weinberg equilibrium and no change in population size, the frequency of heterozygotes after five generations is: a) 0.36     ...
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BIOLOGICAL SCIENCE MCQ 13.07.2021 Practice set

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  BIOLOGICAL SCIENCE MCQ  13.07.2021 Practice set 1. All eukaryotic unicellular organisms belong to a. Monera b. Protista c. Fungi d. Bacteria 2. The five kingdom classification was proposed by a. R.H. Whittaker b. C.Linnaeus c. A. Roxberg d. Virchow 3. Organisms living in salty areas are called as a. Methanogens b. Halophiles c. Heliophytes d. Thermoacidophiles 4. Naked cytoplasm, multinucleated and saprophytic are the characteristics of a. Monera b. Protista c. Fungi d. Slime molds 5. An association between roots of higher plants and fungi is called a. Lichen b. Fern c. Mycorrhiza d. BGA 6. A dikaryon is formed when a. Meiosis is arrested b. The two haploid cells do not fuse immediately c. Cytoplasm does not fuse d. None of the above 7. Contagium vivum fluidum was proposed by a. D.J. Ivanowsky b. M.W. Beijerinek c. Stanley d. Robert Hook 8. Mycobiont and Phycobiont are found in a. Mycorrhiza b. Root c. Lichens d. BGA 9. Difference between Virus and Viroid is a. Absence of pr...
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MCQ BIOLOGY BIOMOLECULES 12.07.2021

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  1.The mature erythrocyte contains a) Cytochromes                          b) TCA – enzymes c) Pyruvic kinase                        d) ATP – ase 2. Hemoglobin is responsible for what percentage of carbondioxide transport by the blood ? a) 90                    b) 50                    c) 10                    d) 5 3. Christmas factor is synonymous with a) Proconvertin                 ...
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