CBSE > Class 12 > Biology | CBSE Board | Homework Help

Ask questions which are clear, concise and easy to understand.

Ask Question

What are the three different ways in which selection may occur

Posted by Saleem Khan 7 years, 3 months ago

CBSE > Class 12 > Biology

0 answers

ANSWER

What happens if we remove thymus gland?

Posted by Mokshad Raj 7 years, 3 months ago

CBSE > Class 12 > Biology

0 answers

ANSWER

Cbse last year question paper 2007 to2014

Posted by K.R Bisen 7 years, 3 months ago

CBSE > Class 12 > Biology

0 answers

ANSWER

How do virus enter plant body and spread tolong distance within it? Mentionany two way by which viruses spread from one plant to another.

Posted by K.R Bisen 7 years, 3 months ago

CBSE > Class 12 > Biology

0 answers

ANSWER

Define reproduction

Posted by Suraj Kumar Singh 7 years, 3 months ago

CBSE > Class 12 > Biology

1 answers

Abhishek Sharma 7 years, 3 months ago

Reproduction is a process by which an organism produce new organism which is similar to itself.

0Thank You

ANSWER

What does ecological nitche of an organisa represent

Posted by K.R Bisen 7 years, 3 months ago

CBSE > Class 12 > Biology

1 answers

Yogita Ingle 7 years, 3 months ago

The ecological niche represents the position and role played by the organism in the ecosystem it lives. The position or the role played in the ecology by the organism is called ecological niche.
Example:- plants they play role as producer, animals play role as consumers and bacteria or insects or vultures/hyena play role as decomposers.

1Thank You

ANSWER

Diagram of l.s of am endospermous monocot seed

Posted by Saleem Khan 7 years, 3 months ago

CBSE > Class 12 > Biology

0 answers

ANSWER

What are cry genes ?

Posted by Manisha Agarwal 7 years, 3 months ago

CBSE > Class 12 > Biology

1 answers

Yogita Ingle 7 years, 3 months ago

Cry genes codes a toxin which is poisonous to some insects thus giving resistant to the plants. They are present in bacterium Bacillus thuringiensis in which it produces a protein toxin which kills insects. The gene encoding Cry protein is called cry gene.

2Thank You

ANSWER

What is central dogma process

Posted by Aravind Kumar 7 years, 3 months ago

CBSE > Class 12 > Biology

1 answers

Gaurav Seth 7 years, 3 months ago

Central dogma of life states the sequential transfer of the information present in the genetic material to be expressed as a character of an individual.

It follows the path shown:

DNA------------------->RNA-------------------->Proteins

The genetic information in the form of DNA is converted into RNA by the process of transcription. The information transcribed on to RNA is expressed as proteins by the process of translation.By following the central dogma of life, a character in the form of gene is expressed in an individual.

0Thank You

ANSWER

What is apiculture

Posted by Varsha Rajput Rajput 7 years, 3 months ago

CBSE > Class 12 > Biology

1 answers

Varsha Rajput Rajput 7 years, 3 months ago

Apiculture is a practice for bee- keeping of the production of various products such as bee , honey,wax ,etc. Honey is highly nutrition food source and it is used an indegenous system of medicine. It is use for making cosmetic, polish ,etc

1Thank You

ANSWER

Why is making cells competent essential for biotechnology experimernts?

Posted by Aman Preet 7 years, 3 months ago

CBSE > Class 12 > Biology

1 answers

Deepa Singh 7 years, 3 months ago

As DNA is a hydrophyllic molecule it cannot pass through the cell membrane of the recipient cell(host cell) so it is essential to make the host competent to take up the recombinant DNA.

1Thank You

ANSWER

Give eg of communalism interaction in plants

Posted by Nargish Pater 7 years, 3 months ago

CBSE > Class 12 > Biology

1 answers

Sunder Singh 7 years, 3 months ago

An orchid growing as an epiphyte on a mango branch but mango tree derives no benefit

2Thank You

ANSWER

Explain the impact of removing of thymus gland on the immune system of human body

Posted by Dipsmita Chattopadhyay 7 years, 3 months ago

CBSE > Class 12 > Biology

1 answers

Sunder Singh 7 years, 3 months ago

It provide micro environment for developement and maturation of t lymphocytes . If we remove thymus than t lymphocytes not mature and not produce immune response.And the receptors present on it not be able to recognize the antigen

0Thank You

ANSWER

What are recipient cells?

Posted by Nargish Pater 7 years, 3 months ago

CBSE > Class 12 > Biology

0 answers

ANSWER

What is the base pairing pattern of DNA ?

Posted by Arti Vishwakarma 7 years, 3 months ago

CBSE > Class 12 > Biology

1 answers

Nargish Pater 7 years, 3 months ago

In dna adenine is joined with thymine through 2 hydrogen bond and guanine is with cytosine through 3 hydrogen bond

1Thank You

ANSWER

What is apomixis? What are it's importance?

Posted by Ammar Khan 7 years, 3 months ago

CBSE > Class 12 > Biology

1 answers

Ankit Soun 7 years, 3 months ago

Apomixis is the process of asexual production of seed without fertilisation. It is cast effective method for producing seed .it has great use for plant breeding when specific trait of a plant have to be preserved

3Thank You

ANSWER

What is sporollien

Posted by Shivam Maurya 7 years, 3 months ago

CBSE > Class 12 > Biology

2 answers

Komal Joshi 7 years, 3 months ago

Sporopollenin is the most resistive element known to us and it is secreted by tapetum which helps in the formation of Exine layer of pollen grain

1Thank You

Adarsh Srivastav 7 years, 3 months ago

Sporopollenin are formed by ubiscbody and it is responsible for formation of outer layer of pollengrain

0Thank You

ANSWER

Define phenotypic adaptation

Posted by Gourav Jhariya 7 years, 3 months ago

CBSE > Class 12 > Biology

1 answers

Yogita Ingle 7 years, 3 months ago

Phenotypic adaptation involves changes in the body of an organism in response to genetic mutation or certain environmental changes. These responsive adjustments occur in an organism in order to cope with environmental conditions present in their natural habitats. For example, desert plants have thick cuticles and sunken stomata on the surface of their leaves to prevent transpiration. Similarly, elephants have long ears that act as thermoregulators.

1Thank You

ANSWER

New pattern biology sample paper are not here

Posted by Tilak Chawla 7 years, 3 months ago

CBSE > Class 12 > Biology

0 answers

ANSWER

What is True breeding line ?

Posted by Arti Vishwakarma 7 years, 3 months ago

CBSE > Class 12 > Biology

1 answers

Deepa Singh 7 years, 3 months ago

A true breeding line is that which have undergone saveral times selfpollination and show stable trait inheritance and expressions for several generation.

1Thank You

ANSWER

Central dogma of life

Posted by Nimal Jrk 7 years, 3 months ago

CBSE > Class 12 > Biology

1 answers

Gaurav Seth 7 years, 3 months ago

Central dogma of life states the sequential transfer of the information present in the genetic material to be expressed as a character of an individual.It follows the path shown:

DNA------------------->RNA-------------------->Proteins

3Thank You

ANSWER

Metabolic activities

Posted by Anushka Gupta 7 years, 3 months ago

CBSE > Class 12 > Biology

1 answers

Gaurav Seth 7 years, 3 months ago

Metabolic activity is the part of metabolism which takes place in the body of an organism. Metabolism is the phenomenon which includes set of chemical reactions which are essential for a living organism to maintain its life. These are also known as metabolic processes. Metabolism can be divided into two processes namely anabolic processes or anabolism and catabolic processes or catabolism

1Thank You

ANSWER

What is codomaince

Posted by Gulshan Kumar 7 years, 3 months ago

CBSE > Class 12 > Biology

1 answers

Deepa Singh 7 years, 3 months ago

Codominance is a type of inheritance in which the offsprings in the F1 generation had a phenotype that resembled both the parents .

1Thank You

ANSWER

Is use of contraceptive method justified give reason .

Posted by Arti Vishwakarma 7 years, 3 months ago

CBSE > Class 12 > Biology

1 answers

Devyanshi Khandelwal 7 years, 3 months ago

Plz clear ur question

0Thank You

ANSWER

What is respiratory system

Posted by Arjun Sing 7 years, 3 months ago

CBSE > Class 12 > Biology

0 answers

ANSWER

Who is the father of taxonomy

Posted by Moni Sharma 7 years, 3 months ago

CBSE > Class 12 > Biology

2 answers

Yogita Ingle 7 years, 3 months ago

Carolus Linnaeus is the father of taxonomy, which is the system of classifying and naming organisms. One of his contributions was the development of a hierarchical system of classification of nature. Today, this system includes eight taxa: domain, kingdom, phylum, class, order, family, genus, and species.

0Thank You

Kirti Singh 7 years, 3 months ago

Carolus Linnaeus

0Thank You

ANSWER

Hey guys how i learn easly definations of bio please ????

Posted by Shobha??? Kumari 7 years, 3 months ago

CBSE > Class 12 > Biology

2 answers

Sunder Singh 7 years, 3 months ago

By break words in definition.

1Thank You

Devyanshi Khandelwal 7 years, 3 months ago

Just by understanding them???

1Thank You

ANSWER

Define back cross with example?

Posted by Harsh Sinha 7 years, 3 months ago

CBSE > Class 12 > Biology

1 answers

Yogita Ingle 7 years, 3 months ago

Back cross is a cross of a hybrid with one of its parents or any individual genetically similar to its parent in order to achieve offspring with genetic identity closer to that of the parent whereas a test cross is a type of back cross between the recessive homozygote and F1 generation.
If the individual being tested produces any recessive offspring its genotype is heterozygous and if all the offspring are phenotypically dominant, its genotype is homozygous.

0Thank You

ANSWER

What is the unit of dna

Posted by Ehteshamul Haque 7 years, 3 months ago

CBSE > Class 12 > Biology

1 answers

Yogita Ingle 7 years, 3 months ago

DNA was discovered by two scientists- Watson and Crick and their model of the structure of DNA are called the Watson and Crick model.The structure of DNA is said to be a double- helical structure with two strands of DNA that are wound around each other. Each strand of DNA is made up of a sequence of nucleotide monomers. Each nucleotide is made up of: