Download Biology mindmap neet and more Schemes and Mind Maps Biology in PDF only on Docsity!
(Divisions of Aakash Educational Services Limited)
BIOLOGY - NCERT UPDATES
FOR CLASS XI
Dear Students and Teachers,
NCERT has revised the previous edition of biology book and incorporated certain new facts, gures and
examples. Ambiguous and controversial facts have also been removed as well as corrections have been
made wherever required.
Aakash brings to you, all the applied changes/additions/deletions in new text of NCERT.
- 17 Table 2.1 Fungal Cell wall : Present (without cellulose) with Chitin
S. No. Pg. No. Previous Content
NCERT
Headings Updated Content
CHAPTER 2- BIOLOGICAL CLASSIFICATION
Fungal Cell wall : Present (without cellulose)
It brought together the prokaryotic bacteria and the blue green algae (Cyanobacteria) with other groups which were eukaryotic.
It brought together the prokaryotic bacteria and the blue green algae with other groups which were eukaryotic.
When your bread develops a mould or your orange rots it is because of fungi. You must have seen fungi on a moist bread and rotten fruits.
2.6 Viruses, Viroids and Lichens 2.6 Viruses, Viroids, Prions and Lichens
In the ve kingdom classication of Whittaker there is no mention of Lichens and some acellular organisms like viruses, viroids, and prions.
In the ve kingdom classication of Whittaker there is no mention of some acellular organisms like viruses and viroids, and lichens.
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.
CHAPTER 3- PLANT KINGDOM
These gametes can be agellated and similar in size (as in Chlamydomonas) or non- agellated (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 agellated and similar in size (as in Ulothrix) or nonagellated (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.
The dicotyledons are characterised by having two cotyledons in their seeds while the monocolyledons have only one. The male sex organs in a ower is the stamen. Each stamen consists of a slender lament with an anther at the tip. The anthers, following meiosis, produce pollen grains. The female sex organs in a ower is the pistil or the carpel. Pistil consists of an ovary enclosing one to many ovules. Within ovules are present highly reduced female gametophytes termed embryo-sacs. The embryo-sac formation is preceded by meiosis. Hence, each of the cells of an embryo-sac is haploid.
The dicotyledons are characterised by seeds having two cotyledons, reticulate venations in leaves, and tetramerous or pentamerous owers, i.e. having four or ve memerbs in each oral whorls. The monocotyledons on the other hand are characterised by single cotyledonous seeds, parallel venation in leaves, and trimerous owers having three members in each oral whorls. The male sex organs in a ower is the stamen. Each stamen consists of a slender lament with an anther at the tip. Within the anthers, the pollen mother cell divide by meiosis to produce microspores which matures into pollen grains. The female sex organs in a ower is the pistil. Pistil consists of an ovary at its base, a long slender style and stigma. Inside the ovary, ovules are present. Generally each ovule has a megaspore mother cell that undergoes meiosis to form four haploid megaspore. Three of them degenerate and one divide to form the embryo sac.
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.
- 17 Introduction
- 21 Fig. 2.
- 31 Fig.3.
10.^40 3.
- 49 Fig.4.
Which contain the stinging capsules or nematocysts
S. No. Pg. No. Previous Content
NCERT
Headings
Updated Content
CHAPTER 4- ANIMAL KINGDOM
Which contain the stinging capsules or nematocytes
Hemichordata have a rudimentary structure in the collar region called stomochord, a structure similar to notochord.
CHAPTER 5- MORPHOLOGY OF FLOWERING PLANTS
Like calyx, corolla may also be gamopetalous (petals united) or polypetalous (petals free).
Like calyx, corolla may be also united gamopetalous (petals united) or polypetalous (petals free)
Gynoecium: bicarpellary obligately placed, syncarpous; ovary superior, bilocular, placenta swollen with many ovules, axile
Gynoecium: bicarpellary, syncarpous; ovary superior, bilocular, placenta swollen with many ovules
- 52 Fig.4.
- 54 Fig.4.
- 69 Fig.5.
- 81 Fig.5.
Active Transport Active transport uses energy to transport and pump molecules against a concentration gradient. Active transport is carried out by specic membraneproteins.
S. No. Pg. No. Previous Content
NCERT
Headings
Updated Content
CHAPTER 11- TRANSPORT IN PLANTS
Active Transport Active transport uses energy to pump molecules against a concentration gradient. Active transport is carried out by membrane-proteins.
If some solute is dissolved in pure water, the solution has fewer free water molecules and the concentration (free energy) of water decreases, reducing its water potential.
If some solute is dissolved in pure water, the solution has fewer free water and the concentration of water decreases, reducing its water potential.
In large and complex organisms, often substances have to be moved across very In large and complex organisms, often substances have to be moved long distances large distances
CHAPTER 13- PHOTOSYNTHESIS IN HIGHER PLANTS
You have studied the structure of chloroplast in Chapter 8. Within the chloroplast there is the membranous system consisting of grana, the stroma lamellae, and the uid stroma (Figure 13.2). There is a clear division of labour within the chloroplast. The membrane system is responsible for trapping the light energy and also for the synthesis of ATP and NADPH. In stroma, enzymatic reactions incorporate CO into 2 the plant leading to the synthesis of sugar, which in turn forms starch. The former set of reactions, since they are directly light driven are called light reactions. The latter are not directly light driven but are dependent on the products of light reactions (ATP and NADPH). Hence, to distinguish the latter they are called, by convention, as dark reactions.
You have studied the structure of chloroplast in Chapter 8. Within the chloroplast there is the membranous system consisting of grana, the stroma lamellae, and the matrix stroma (Figure 13.2). There is a clear division of labour within the chloroplast. The membrane system is responsible for trapping the light energy and also for the synthesis of ATP and NADPH. In stroma, enzymatic reactions synthesise sugar, which in turn forms starch. The former set of reactions, since they are directly light driven are called light reactions (photochemical reactions). The latter are not directly light driven but are dependent on the products of light reactions (ATP and NADPH). Hence, to distinguish the latter they are called, by convention, as dark reactions (carbon reactions).
Transfer to another accepter, and nally down hill to NADP+ causing it to be reduced to NADPH + H+ is called the Z scheme, due to its characterstic shape (Figure 13.5).
Transfer to another accepter, and nally down hill to NADP+ reducing it to NADPH + H+ is called the Z scheme, due to its characterstic shape (Figure 13.5).
Why are we so interested in the proton gradient? This gradient is important because it is the breakdown of this gradient that leads to release of energy.
Why are we so interested in the proton gradient? This gradient is important because it is the breakdown of this gradient that leads to synthesis of ATP
Of the F0 of the ATPase. The ATPase enzyme consists of two parts: one called the F0 is embedded in the membrane and forms a transmembrane channel that carries out facilitated diffusion of protons across the membrane. The other portion is called F and protrudes on the outer surface of the hylakoid membrane on the side that faces the stroma. The break down of the gradient provides enough energy to cause a conformational change in the F1 particle of the ATPase, which makes the enzyme synthesise several olecules of energy-packed ATP. Chemiosmosis requires a membrane, a proton pump, a proton gradient and ATPase. Energy is used to pump protons across a membrane, to create a gradient or a high concentration of protons within the thylakoid lumen. ATPase has a channel that allows diffusion of protons back across the membrane; this releases enough energy to activate ATPase enzyme that catalyses the formation of ATP.
Of the CF 0 of the ATP synthase. The ATP synthase enzyme consists of two parts: one called the CF0 is embedded in the thylakoid membrane and forms a transmembrane channel that carries out facilitated diffusion of protons across the membrane. The other portion is called CF1 and protrudes on the outer surface of the thylakoid membrane on the side that faces the stroma. The break down of the gradient provides enough energy to cause a conformational change in the CF1 particle of the ATP synthase, which makes the enzyme synthesise several molecules of energy-packed ATP. Chemiosmosis requires a membrane, a proton pump, a proton gradient and ATP synthase. Energy is used to pump protons across a membrane, to create a gradient or a high concentration of protons within the thylakoid lumen. ATP synthase has a channel that allows diffusion of protons back across the membrane; this releases enough energy to activate ATP synthase enzyme that catalyses the formation of ATP.
- 182 Fig. 11.
- 214 Fig.13.
- 219 Fig.13.
- 233 Fig.14.
S. No. Pg. No. Previous Content
NCERT
Headings
Updated Content
CHAPTER 14- RESPIRATION IN PLANTS
Stomach has three parts cardiac, fundic and pyloric Stomach has four parts cardiac,fundic, body and pyloric parts
Diagram of ETS in previous of NCERT XI denotes oxidation of NADH+H+ only ,so there were 3 pairs of protons i.e. 6H+ released into the ntermembrane space but in new diagram of ETS, oxidation of NADH+H+ and FADH2 both are included so total protons in intermembrane space become ten i.e. 10 H + .Now according to NCERT's Concept [2H+ for 1 ATP].we conclude these 10H+ in following manner: 1.Release of 6H+ due to oxidation of NADH+H+ =3ATP 2.Release of 4H+ due to oxidation of FADH2 =2ATP
CHAPTER 16- DIGESTION AND ABSORPTION
U shaped duodenum C shaped duodenum
However,some of the substances like glucose and some amino acids are absorbed with the help of the carrier proteins. This mechanism is called the facilitated transport.
However,some of the substances like fructose and some amino acids are absorbed with the help of the carrier ions like Na+. This mechanism is called the facilitated transport.
CALORIFIC VALUE OF PROTEIN, CARBOHYDRATE AND FAT
(Boxed item – Not for evaluation)* The energy requirements of animals, and the energy content of food, are expressed in terms of measure of heat energy because heat is the ultimate form of all energies. This is often measured to as calorie (cal) or joule (J), which is the amount of heat energy required to raise the temperature of 1 g of water by 1 °C. Since this value is tiny amount of energy, physiologists commonly use kilocalorie (kcal) or kilo joule (kJ). One kilo calorie is the amount of energy required to raise the temperature of 1 kg of water by 1 °C. Nutritionists, traditionally refer to kcal as the Calorie or Joule (always capitalised). The amount of heat liberated from complete combustion of 1 g food in a bomb calorimeter (a closed metal chamber lled with O2) is its gross caloric or gross energy value. The actual amount of energy combustion of 1 g of food is the physiologic value of food. Gross caloric values of carbohydrates, proteins and fats are 4.1 kcal/g, 5.65 kcal/g and 9.45 kcal/g, respectively, whereas their physiologic values are 4. kcal/g, 4.0 kcal/g and 9.0 kcal/g, respectively.
- 258 Fig.16.
- 259 Fig.16.
- 261 Fig.16.
S. No. Pg. No. Previous Content
NCERT
Headings
Updated Content
CHAPTER 22- CHEMICAL COORDINATION AND INTEGRATION
Excess secretion of growth hormone in adults especially in middle age can result in severe disgurement (especially of the face) called Acromegaly, which may lead to serious complications,and premature death if unchecked. The disease is hard to diagnose in E108the early stages and often goes undetected for many years, until changes in external features become noticeable.*
An impairment affecting synthesis or release of ADH results in a diminished ability of the kidney to conserve water leading to water loss and dehydration. This condition is known as Diabetes Insipidus*
Exopthalmic goitre is a form of hyperthyroidism, characterised by enlargement of the thyroid gland, protrusion of the eyeballs, increased basal metabolic rate, and weight loss, also called Graves’ disease*
Underproduction of hormones by the adrenal cortex alters carbohydrate metabolism causing acute weakness and fatigue leading to a disease called Addison’s disease*
- This content was previously given as Supplementary Material at the end of the NCERT book and now added in the main text of their respective chapters.
Regd. Ofce : Aakash Tower, 8, Pusa Road, New Delhi-110005 | Ph.: 011-
