Dr.SadhanaNikam'sbiology.blogspot.com

  Prof.Dr.Sadhana Nikam Vice Principal Rashtriya Jr. College, Chalisgaon Biology Subject Notes of XII Science Ch.14 Ecosystems and Energy flow Introduction : Def : Ecosystem *A self regulatory & self sustaining  structural and functional unit of biosphere is called an Ecosystem. * Tansley (1935) coined the term  ecosystem. * Types of Ecosystem: *Natural  ecosystem : The ecosystems which operate under natural conditions without any  interference of man are called Natural  Ecosystems. * Artificial ecosystems : The ecosystems which made and maintained artificially  by  man are called  Artificial ecosystems. 14.5 Ecological Succession : Q.What is mean by Ecological Succession (1 Mks) Def: The gradual & predictable change in the species composition of a given area is called Ecological succession. Q. What is climax community (1 Mks) Species diversity increase by sequential change in a definite order relating with time to for...

  Prof.Dr.Sadhana Nikam Vice Principal Rashtriya Jr. College, Chalisgaon Biology Subject Notes of XII Science Ch.7 Plant Growth and Mineral Nutrition Introduction : *Growth has two aspects as quantitative and qualitative. *Growth can be defined as permanent   irreversible   increase   in weight of an  organism with change in their form. 7.9  Growth Hormones : Q. Who coined the term Hormone(1 Mark) Starling first coined the term hormone in 1906.   Q.Define Growth hormones (1 Mark) The internal factors that influence growth are called Growth Hormones.   Q.Why  Growth hormones  are  called  Growth regulators       (1 Mark)    As Growth hormones  inhibit  promote  or  modify  the plant growth  they  are called  as  Growth  regulators.    Q. Enlist  the  names  of  Growth  Promoters (1 Mark)      ...

  Prof.Dr.Sadhana Nikam Vice Principal Rashtriya Jr. College, Chalisgaon Biology Subject Notes of XII Science CH.6 Plant Water Relation  INTRODUCTION * Plant obtain variety of substances like water,minerals, nutrients, food and gases like O2 and CO2   *Water is considered as ‘elixir of life’ 6.1   Properties of Water : Q. Describe Properties of Water(2 Mks) 1. Water occur in liquid form at room temperature. 2. Water is best solvent for most of solutes. 3. Water is inert inorganic  compound  with neutral pH. 4. Water is best aqueous  medium  for  all  biochemical  reactions in the cells. 5. Water has high specific heat,high heat of vaporization and high heat of fusion. 6. Water molecules have good adhesive and cohesive forces of attraction. 6.2 Water absorbing organ Root : 1. Root is the main organ of water and mineral absorption. 2. Terrestrial plants absorb water in the form of liquid from the soil. 3. ...