During Grams' staining which is incorrect?
(1) All bacteria take crystal violet stain
(2) Gram +ve bacteria take crystal violet stain
(3) Only Gram –ve bacteria take crystal violet stain
(4) Gram –ve bacteria lose this stain after alcohol
Audio Explanation:
Please note that the above question is asking which option is incorrect. "Only" keyword in option 3 makes that incorrect statement as both Gram +ve and -ve bacteria take crystal voilet stain. So, option (3) is the answer here.
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Hammerling's experiments on Acetabularia involved exchanging
(1) Cytoplasm
(2) Nucleus
(3) Rhizoid and stalk
(4) Gametes
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A non-membrane bound organelle found exclusively in animal cells is:
1. Sphaerosome
2. Glyoxisome
3. Peroxisome
4. Centriole
Centrioles are not membrane bound and are involved in spindle formation. They are usually associated with animal cells and are absent in angiosperms and most fungi. The most appropriate answer is, therefore, centriole.
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Which of the following are the largest constituentof a typical cell membrane and are also responsible for performing most of the functions of the membrane?
1.Proteins
2.Lipids
3.Glycolipids
4.Glycoproteins
A typical cell membrane like that of RBC has about 52% proteins. While the structure is made of lipids, the functions are carried out by proteins such as being channels and carrier proteins.
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Cell is the fundamental structural and functional unit of all living organisms because:
(1) Anything less than a complete structure of a cell does not ensure independant living.
(2) The metabolic reactions can only occur inside a living cell.
(3) Nucleic acids present in the cells ensure living state.
(4) The membrane bound organelles cause differentiation for proper functioning.
(1) read page 125 XI NCERT
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Who concluded, based on his studies on plant tissues, that the presence of cell wall is a unique character of plant cells ?
(1) Mathias Schleiden
(2) Theodore Schwann
(3) Rudolph Virchow
(4) Robert Hooke
(2) Read page 126 XI NCERT
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Mesosomes in prokaryotes do not help in:
1. Cell wall formation
2. DNA replication
3. Respiration
4. Photosynthesis
(4) Read page 128/129 XI NCERT
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The endomembrane system of a eukaryotic cell does not include:
1. Endoplasmic reticulum
2. Lysosome
3. Vacuole
4. Peroxisome
Answer: 4
Read page 133 XI NCERT
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The cis and trans faces of the Golgi Apparatus are:
1. Similar but not interconnected
2. Similar and interconnected
3. Entirely different but interconnected
4. Entirely diffrent and not interconnected
3. Read page 134 XI NCERT
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Plastids used in storing proteins are called as:
(1) Amyloplasts
(2) Aleuroplasts
(3) Elaioplasts
(4) Chromoplasts
(2) Read page 135 XI NCERT
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