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

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

Ask Question

Offspring formed due to sexual reproduction have better chances of survival.why?

Posted by Mahek Patel 4 years, 5 months ago

1 answers

Gaurav Bagga 4 years, 5 months ago

Because it results into variations in the genome of the offsprings which helps them for better adaptation in the changing environment.

0Thank You

ANSWER

What is the difference between in vitro fertilisation and in vitro studies?

Posted by John Rose Nesamony 4 years, 2 months ago

CBSE > Class 12 > Biology

0 answers

ANSWER

Give reason why Marchantia is considered dioecious.

Posted by Diwakar Khandelwal 4 years, 5 months ago

CBSE > Class 12 > Biology

1 answers

Hey Kriti 4 years, 5 months ago

Marchantia is considered dioecious because Both *** organs in the separate individuals.

0Thank You

ANSWER

Give reason why bamboo plants are considered to have unusual flowering response.

Posted by Diwakar Khandelwal 4 years, 5 months ago

CBSE > Class 12 > Biology

1 answers

Hey Kriti 4 years, 5 months ago

Flowering in Bamboo plant is considered a unique flowering process because this type of flowering is very rare and unique in plant kingdom. Bamboo plant produces spectacular flowers once every 60 to 130 years, depending upon the species. Similarly, a plant of Neela kuranagi exhibit flowers once in 12 years.

0Thank You

ANSWER

Define cleistogamous ...

Posted by Jinu ??? 4 years, 5 months ago

CBSE > Class 12 > Biology

3 answers

Jass . 4 years, 5 months ago

Cleistogamous flowers are closed flowers. They have anther and stigma within the closed flower. In them self pollination take place. They do not require pollinating agencies. Examples- viola , peanut , pea

2Thank You

Nupur Sengar 4 years, 5 months ago

Flower that do not open.

1Thank You

Hey Kriti 4 years, 5 months ago

Flowers which are open are called cleistogamous.

1Thank You

ANSWER

Give reason why water hyacinth is called as invasive weed.

Posted by Diwakar Khandelwal 4 years, 5 months ago

CBSE > Class 12 > Biology

1 answers

Hey Kriti 4 years, 5 months ago

Water hyacinth reproduces vegetatively by off sets. It propagate, vegetatively, at an enormous and alarming rate. Therefore it spreads all over the water body and fully covers it within a short period of time. Thus, it has become the most invasive aquatic weed.

1Thank You

ANSWER

Give reason why mammals living in natural wild condition are seasonal breeders.

Posted by Diwakar Khandelwal 4 years, 5 months ago

CBSE > Class 12 > Biology

1 answers

Hey Kriti 4 years, 5 months ago

Many mammals, especially those living in natural wild conditions exhibit reproductive cycles only during favourable seasons in their reproductive phase and are therefore called seasonal breeders.

0Thank You

ANSWER

Give reason why rotifers are called as parthenocarpic organism.

Posted by Diwakar Khandelwal 4 years, 5 months ago

CBSE > Class 12 > Biology

2 answers

Prachi Prachi 4 years, 3 months ago

The question is about parthenocarpic not parthenogenesis so tell Answer according to question?

1Thank You

Shagun Sharma 4 years, 3 months ago

the phenomenon in which the egg or ovum develops into an embryo and then into a new organism without the act of fertilization is called parthenogenesies e.g. male honeybee rotifers and green algae like ulothrix.

0Thank You

ANSWER

How is sexuality of papaya plant different from a maize plant?

Posted by Diwakar Khandelwal 4 years, 5 months ago

CBSE > Class 12 > Biology

1 answers

Hey Kriti 4 years, 5 months ago

The sexuality is different because the sexes in the papaya plant are found on different trees , the male is on a different tree while the female is in a different tree while the sexes of the maize plant are found on the same plant.

1Thank You

ANSWER

Differentiate between pre fertilization and post fertilization.

Posted by Diwakar Khandelwal 4 years, 5 months ago

CBSE > Class 12 > Biology

0 answers

ANSWER

What is gel electrophoresis?

Posted by Isha Antil 4 years, 5 months ago

CBSE > Class 12 > Biology

1 answers

Hey Kriti 4 years, 5 months ago

It is a technique used to separate DNA fragments.

1Thank You

ANSWER

In megasporogenesis the nucleus are divided from same origin so why after dividing their functions are different (Ch 2)

Posted by # Bharat 4 years, 5 months ago

CBSE > Class 12 > Biology

1 answers

# Bharat 4 years, 5 months ago

Thanks

1Thank You

ANSWER

Characteristics of life span

Posted by Anjali Kumari 4 years, 5 months ago

CBSE > Class 12 > Biology

1 answers

Sia ? 4 years, 5 months ago

Key characteristics of life-span development

Development is multidirectional.
Development is plastic.
Development is dependent on history and context.
Development is multidisciplinary.
Development is contextual.
Development Involves Growth, Maintenance, and Regulation of Loss.
Theme 2.
Biological Processes.

1Thank You

ANSWER

Which of the following structures are found in fallopian tube? Morula, secondary oocyte, primary oocyte, secondary follicle, ovum, zygote, blastula, gastrula.

Posted by Shivam Agrawal 4 years, 5 months ago

CBSE > Class 12 > Biology

3 answers

Shivam Agrawal 4 years, 5 months ago

Secondary oocyte, ovum, zygote, morula

2Thank You

Hey Kriti 4 years, 5 months ago

Zygote

0Thank You

Hey Kriti 4 years, 5 months ago

Secondary oocyte, primary oocyte, secondary follicle, ovum

0Thank You

ANSWER

Name the functions of Corpus luteum endometrium acrosome of sperm tail fimbria

Posted by Jai Yadav 4 years, 5 months ago

CBSE > Class 12 > Biology

2 answers

Devil ? 4 years, 5 months ago

Corpus luteum release the hormone called progesterone... acrosome contains hyluronidiand acrosin.. sperm tail help in the movement of sperm... Fimbrae help in catching of egg from the ovary endometrium has been implantation of zygote

0Thank You

Kavya S 4 years, 5 months ago

Corpus luteum- for synthesis of progesterone, endometrium- implantation of zygote,acrosome- energy for sperms, fimbria- collection of ova

0Thank You

ANSWER

What are difference between meiotic and meiosis division?

Posted by Ashutosh Bind 4 years, 5 months ago

CBSE > Class 12 > Biology

2 answers

Hey Kriti 4 years, 5 months ago

Meiosis is a type of cell division that results in the formation of four daughter cells each with half the number of chromosomes as the parent cell. Mitosis is the type of cell division that results in the formation of two daughter cells each with the same number and kind of chromosomes as the parent cell.

2Thank You

Kavya S 4 years, 5 months ago

I think so both are same

1Thank You

ANSWER

Compare in any three ways the chromosomal theory of inheritance

Posted by Omish Garg 4 years, 5 months ago

CBSE > Class 12 > Biology

0 answers

ANSWER

Hai guys ! My friend was Ill and not completed study for board exams still now.Pls say some ideas and tips for her to get 450+ in exams . She is school topper in 10th class got 475 + marks in board

Posted by Kavya S 4 years, 5 months ago

CBSE > Class 12 > Biology

2 answers

Kavya S 4 years, 5 months ago

Thank u for ur wishes divyashree ? Same too u?

5Thank You

Dhivyasree Mohan 4 years, 5 months ago

There is no shortcut for success kavya..so she should give her utmost effort to get succeded in her aim..this yr qn.ppr will also be ec..so ask her not to worry.. wishing u and ur friend a very all the best --??

4Thank You

ANSWER

What is the explanations of microbes and its uses

Posted by Aniket Singh 4 years, 5 months ago

CBSE > Class 12 > Biology

1 answers

Hey Kriti 4 years, 5 months ago

* Microbes are diverse-protozoa, bacteria, fungi and microscopic plants viruses, viroid and also prions that are proteinacious infectious agents. * They are found everywhere on earth ranging from soil, air water and some inhabitable places. * Bacteria and fungi can be grown on nutritive media to form colonies, which can be seen by necked eyes and very useful in study of microorganisms. *Microbes cause many diseases in human beings, plants and animals. Several microorganisms are useful to man in diverse ways.

0Thank You

ANSWER

What is red list? Give two uses of red list

Posted by Afreen Hossain 4 years, 5 months ago

CBSE > Class 12 > Biology

1 answers

Kavya S 4 years, 5 months ago

The Red List tells us which species are most in danger and which to conserve first. It is also a powerful tool for persuading governments to protect threatened species, and for most of the plant and animal species worldwide, it is vital

0Thank You

ANSWER

Name the category of virus that carries reverse transcriptase? What is the purpose of this enzyme. 22. Give the technical terms for the following:

Posted by Afreen Hossain 4 years, 5 months ago

CBSE > Class 12 > Biology

2 answers

Hey Kriti 4 years, 5 months ago

Retrovirus carries reverse transcriptase. Reverse transcriptase converts RNA into DNA.

1Thank You

Kavya S 4 years, 5 months ago

Retrovirus

1Thank You

ANSWER

What is Klinefelter's syndrome ?

Posted by Dhruv Garg 4 years, 5 months ago

CBSE > Class 12 > Biology

2 answers

Sia ? 4 years, 5 months ago

Klinefelter syndrome is one of the genetic disorders in males. It occurs when a male baby is born with more than required or extra X chromosomes. Many males consist of one X and one Y chromosome and an extra chromosome can cost a male with physical traits which are inappropriate for males.

0Thank You

Hey Kriti 4 years, 5 months ago

Klinefelter's syndrome is due to the presence of an extra copy of x-chromosomes in males like 44+xxy, 44+xxxy, etc. The affected individuals are phenotypically males. Symptoms - underdeveloped testes, presence of breaat-like structure, little growth of hair on face and body, no sperm formation, etc.

0Thank You

ANSWER

Body content

Posted by Ankita Channewar 4 years, 5 months ago

CBSE > Class 12 > Biology

0 answers

ANSWER

Why Transcription and Translation are coupled in prokaryotes

Posted by Omkar Padhy 4 years, 5 months ago

CBSE > Class 12 > Biology

2 answers

Dhruv Garg 4 years, 5 months ago

This is because there is no nucleus in prokaryotes that separates the transcription and translation process. Therefore, when bacterial genes are transcribed then transcripts begin to translate immediately. Prokaryotic transcription occurs in the cytoplasm alongside translation and both processes occur simultaneously.

0Thank You

Vaibhav Kumar 4 years, 5 months ago

I don't know

1Thank You

ANSWER

What is sporangenesis

Posted by Abhay Rajpoot 4 years, 5 months ago

CBSE > Class 12 > Biology

3 answers

Dhruv Garg 4 years, 5 months ago

Google it out

0Thank You

Vignesh.S Vicky 4 years, 5 months ago

The process of transfer of spermatids into sperm is known as Spermiogenesis

1Thank You

Aditya Mishra 4 years, 5 months ago

The answer is hidden in the word...genesis means formation ...so it is simply the process of formation of spores

2Thank You

ANSWER

What is mitosis and meiosis

Posted by Anushka Singh 4 years, 5 months ago

CBSE > Class 12 > Biology

0 answers

ANSWER

How a bt cotton made to attain resistance against ballworm?

Posted by Rupali Soni 4 years, 5 months ago

CBSE > Class 12 > Biology

1 answers

Kavya S 4 years, 5 months ago

Specific Bt toxin genes were isolated from bacillus thuringlensis and incorporated into the several crop plants such as cotton. The choice of genes depends upon the crop and the targeted pest, as most Bt toxins are insect group specific. 2. The toxin is coded by a gene name cry. There a number of them, for example, the proteins encoded by the genes cryIAc and cryIIAb control the cotton bollworms, and that of cryIAb controls corn borer.,

0Thank You

ANSWER

Class 12 ke jo?‍??‍??‍??‍? stidents biology mai sample paper? lena chah rahe hai mai unhe XAMIDEA? chapterwise suggest kar rhi hu Kyuki ,,,sample paper Accha hai uske saare chapter ke concept acche hai And this will more helps in your exam preparation ???✌✌✌✌✌ ■☺☺BEST OF LUCK ??■

Posted by Aahana ❄❄ 4 years, 5 months ago

CBSE > Class 12 > Biology