Skip to main content

Online notes for biology class 11 - What are theories of a Cell?

What are theories of a Cell? Online notes for biology class 11 

Cell Theories’ from Unit 3 – Chapter 8 Biology Class 11- Modern Version of Cell Theory

According to this theory-
  1. All living organisms (animals, plants or microbes) are made up of one or more cells or cell products.
  2. All metabolic reactions in unicellular and multicellular organisms take place inside the cells.
  3. Cells originate from other cells, i.e. no cells can originate spontaneously or de novo, but comes into being only by cell division and duplication of already existing cells.
The exception to Cell Theory
Cell theory does not have universal application, this means, there are certain living organisms which do not have true cells. A true cell has following characteristics-
  1. A set of genes (the functional region of DNA) which constitutes the blueprints for regulating cellular activities and makes new cells.
  2. A plasma membrane that permits controlling the exchange of matter and energy from outside.
  3. Metabolic machinery for sustaining life activities such as growth, reproduction, and repair of cells.

Read full article click What are theories of a Cell?

For School courses, Professional courses, and Skill development courses, Class 11 and 12 online classes kindly visit www.takshilalearning.com

Comments

Popular posts from this blog

Lessons-Worksheets-Question Papers-CBSE Class 2 English

Lessons-Worksheets-Question Papers-CBSE Class 2 English CBSE 2nd Class English – One and Many  In this blog, we share the spelling rules used in the concept of  One  and Many. When there is only one of a naming word (noun), it is said to be a  singular noun . When a noun shows more than one, it is said to be in the  plural . We can add  –S, -es, -ves or ies  to show that there is more than one noun.  For example,  we say many birds, four biscuits, six brushes. But for the students of  Class 2 , it’s very difficult and confusing to understand where to use  s , es, ves or ies  in the form of many. Don’t worry, it looks difficult, but it is very easy as in grammar each concept has a set of rules that need to practice. Noun ending with  –s, -x, -o, -sh, -ch, and –ss  form plurals by taking  –es. Look at these pairs of words: Bus – Buses Brush – Brushes Continue ..... Click here ...

Allotment of DIN (Director Identification Number)

Allotment of DIN (Director Identification Number) CS professional course :  Section 153 of the Companies Act, 2013 read with Rule 9 of the Companies (Appointment and Qualification of Directors) Rules, 2014 Every individual intending to be appointed as a director as a director of a company shall make an application for allotment of Director Identification Number (DIN) to the Central Government in such form and manner and along with such fees as may be prescribed. Rule 9 of Companies (Appointment and Qualification of Directors) Rules, 2014 (1) Every Individual, who is to be appointed as a director of a company shall make an application electronically in Form DIR 3, to the Central Government for the allotment of a DIN along with such fees as provided in the Companies (Registration Offices and Fees) Rules, 2014. (2) The Central Government shall provide an electronic system to facilitate submission of an application for the allotment of DIN through the portal on the MCA21...

Class 3 English Practice Grammar Worksheet -The Adverb

 Class 3 English Practice Grammar Worksheet -The Adverb Class 3 English – The Adverb – Kinds of Adverb Fill in the blanks with suitable Adverbs of place. Choose from the box.  Up               outside                       everywhere                 back                down      away          here                           there                     ...