here have been some major changes in NCERT biology.
Changes in NCERT Biology will impact somehow on NEET & AIIMS 2019 Exam.
There have been some major changes in NCERT biology.

Here We have Discussed Major 11th Changes in NCERT Biology.

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Biological Classification
Pg. No. Previous Content Updated Content
17 Fungal Cell wall : Present (without cellulose) Fungal Cell wall : Present (without cellulose) with Chitin
7 It brought together the prokaryotic bacteria and the blue green algae with other groups which were eukaryotic. It brought together the prokaryotic bacteria and the blue green algae (Cyano bacteria) with other groups which were eukaryotic
21
22 When your bread develops a mould or your orange rots it is because of fungi. When your bread develops a mould or your orange rots it is because of fungi.
25 2.6 VIRUSES, VIROIDS AND LICHENS 2.6 VIRUSES, VIROIDS, PRIONS AND LICHENS
25 In the five kingdom classification of Whittaker there is no mention of some acellular organisms like viruses and viroids, and lichens. These are briefly introduced here.
A
ll of us who have suffered the illeffects of common cold or flu’ know what effects viruses can have on us, even if we do not associate it with our condition. Viruses did not find a place in classification since they are not truly ‘living, if we understand living as those organisms that have a cell structure.
In the five kingdom classification of Whittaker there is no mention of Lichens and some acellular organisms like viruses, viroids, and prions. These are briefly introduced here.
A
ll of us who have suffered the ill effects of common cold or flu’ know what effects viruses can have on us, even if we do not associate it with our condition. Viruses did not find a place in classification since they are not considered truly ‘living, if we understand living as those organisms that have a cell structure.
27   Prions :
In modern medicine certain infections
neurological diseases were found to be transmitted by an agent consisted of abnormally folded protein. The agent was similar in size to viruses. These agents were called prions. The most notable diseases caused by prions are bovine spongiform encephalopathy (BSE) commonly called mad cow disease in cattle and its analogous variant Cr-Jacob disease (CJD) in humans.
Plant Kingdom
30 These gametes can be flagellated and similar in size (as in Chlamydomonas) or non-flagellated (non-motile) but similar in size (as in Spirogyra). Such reproduction is called isogamous. Fusion of two gametes dissimilar in size, as in some species of Chlamydomonas is termed as anisogamous. These gametes can be flagellated and similar in size (as in Ulothrix) or non- flagellated (non-motile) but similar in size (as in Spirogyra). Such reproduction is called isogamous. Fusion of two gametes dissimilar in size, as in species of Udorina is termed as anisogamous.
31  

40 All seed-bearing plants i.e. gymnosperms and angiosperms, follow this pattern (Figure 3.7 b). An alga, Fucus sp., represents this pattern (Fig. 3.7b). In addition, all seed bearing plants i.e., gymnosperms and angiosperms, follow this patterns with some variations, wherein, the gametophytic phase is few to multi-celled.
Animal Kingdom
49
52
54
54   para 4.2.10 added after line 3 - (Hemichordata have a rudimentary structure in the collar region called stomochord, a structure
similar to notochord.)
Morphology of flowering plants
Pg. No. Previous Content Updated Content
69
73 Like calyx, corolla may be also free (gamopetalous) or united (polypetalous). Like calyx, corolla may also be gamopetalous (petals united)
or polypetalous (petals free).
80 Gynoecium: bicarpellary, syncarpous; ovary superior, bilocular, placenta
s
wollen with many ovules
Gynoecium: bicarpellary obligately placed, syncarpous; ovary superior, bilocular, placenta swollen with many ovules, axile
81
Anatomy of flowering Plants
Pg. No. Previous Content Updated Content
90 When xylem and phloem within a vascular bundle are arranged in an alternate manner on different radii, the arrangement is called radial such as in roots. In conjoint type of vascular bundles, the xylem and phloem are situated at the same radius of vascular bundles. When xylem and phloem within a vascular bundle are arranged in an alternate manner on different radii, the arrangement is called radial such as in roots. In conjoint type of vascular bundles, the xylem and phloem are situated at the same radius of vascular bundles.
90 The outermost layer is epidermis. Many of the epidermal cells protrude in the form of unicellular root hairs. The outermost layer is epiblema. Many of the cells of epiblema protrude in the form of unicellu

Cell: The Unit of Life
Pg. No. Previous Content Updated Content
136  
136 The eukaryotic ribosomes are 80S while the prokaryotic ribosomes are 70S. Here S’ stands for the sedimentation coefficient; it indirectly is a measure of density and size. Both 70S and 80S ribosomes are composed of two subunits The eukaryotic ribosomes are 80S while the prokaryotic ribosomes are 70S. Each ribosome has two subunits, larger and smaller subunits (fig. 8.9) The two subunits of 80S ribosomes are 60S and 40S while that of 70S ribosomes are 50S and 30S. Here ‘S’ (Svedberg's Unit) stands for the sedimentation coefficient; it indirectly is a measure of density and size. Both 70S and 80S ribosomes are composed of two subunits.
Biomolecules
144 Oils have lower melting point (e.g., gingely oil) and hence remain as oil in winters. Oils have lower melting point (e.g., gingelly oil) and hence remain as oil in winters.
150
Cell Cycle and Cell Division
163
164 Prophase which is the first stage of mitosis follows the S and G2 phases of interphase. Prophase which is the first stage of karyokinesis of mitosis follows the S and G2 phases of interphase.
164 Initiation of the assembly of mitotic spindle, the microtubules, the proteinaceous components of the cell cytoplasm help in the process. Centrosome which had undergone duplication during interphase  , begins to move towards opposite poles of the cell. Each centrosome radiates out microtubules called asters. The two asters together with spindle fibres forms mitotic apparatus.
166 10.2.4 Telophase

At the beginning of the final stage of mitosis, i.e., telophase, the chromosomes that have reached their respective poles decondense and lose their individuality. The individual chromosomes can no longer be seen and chromatin material tends to collect in a mass in the two poles (Figure10.2 d).

10.2.4 Telophase
A
t the beginning of the final stage of karyokinesis, i.e., telophase, the chromosomes that have reached their respective poles decondense and lose their individuality. The individual chromosomes can no longer be seen and each set of chromatin material tends to collect at each of the two poles (Figure 10.2 d).
166 Nuclear envelope assembles around the chromosome clusters. Nuclear envelope develops around the chromosome clusters at each pole forming two daughter nuclei.
166 10.2.5 Cytokinesis
M
itosis accomplishes not only the segregation of duplicated chromosomes into daughter nuclei (karyokinesis), but the cell itself is divided into two daughter cells by a separate process called cytokinesis at the end of which cell division is complete (Figure 10.2 e).
10.2.5 Cytokinesis
M
itosis accomplishes not only the segregation of duplicated chromosomes into daughter nuclei (karyokinesis), but the cell itself is divided into two daughter cells by the separation of cytoplasm called cytokinesis at the end of which cell division gets completed (Figure 10.2 e).
167 Meiosis involves pairing of homologous chromosomes and recombination between them. Meiosis involves pairing of homologous chromosomes and recombination between non-sister chromatids of homologous chromosomes.
168 During this stage bivalent chromosomes now clearly appears as tetrads. During this stage, the four chromatids of each bivalent chromosomes becomes distinct and clearly appears as tetrads.
169 The stage between the two meiotic divisions is called interkinesis and is generally short lived. The stage between the two meiotic divisions is called interkinesis and is generally short lived.There is no replication of DNA during interkinesis.
169 Anaphase II: It begins with the simultaneous splitting of the centromere of each chromosome (which was holding the sister chromatids together), allowing them to move toward opposite poles of the cell (Figure 10.4). Anaphase II: It begins with the simultaneous splitting of the centromere of each chromosome (which was holding the sister chromatids together), allowing them to move toward opposite poles of the cell (Figure 10.4) by shortening of microtubules attached to kinetochores.

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Important Changes In 12th NCERT Biology

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