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Because in summer the temperature of body increase fastly that leads to dehydration to complete the need of body's water requrment and maintaining the body temperature and protecting from dehydration we drink more water in summer.

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In ambryogenesis development of zygote or ambryo

Posted by Vaibhav Gupta 6 years, 8 months ago

CBSE > Class 12 > Biology

2 answers

Ruchi Harariya 6 years, 8 months ago

Abously embryo

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Kartik Sharma 6 years, 8 months ago

Embryogenesis is the process in which the fully developed zygote is starterd getting devlope in embryo

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Describe the development of embryo sac?

Posted by Mega Cloud 6 years, 8 months ago

CBSE > Class 12 > Biology

1 answers

Raghav Patidar 6 years, 8 months ago

Development of embryosac (also known as monosporic development) archegonial cell present in the nucellus divides periclinally to form outer primary parietal cell and inner primary sporogenous cell . With time parietal cell denerates and sporonenous tissue behaves as megaspore mother cell. Meosis in MMC results in production of 4 haploid cell. With time 3 cells of micropyler end get denerates and 1cell at chalazal end remain functional and called functional megaspore . Functinal megaspore turn over 3 mitosis results in 8 haploid cells 4 at micropyler end and 4 at chalazal end Now 1 cell from each end comes in center to form secondary nucleus and remaning 3 cells of micropyler end form egg appratus and remaining 3 cells of chalazal end form antipodals Egg apparatus consists of two haploid synergid and 1 egg This is the development of embryosac

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What is called appomix?what are it's advantages and disadvantages

Posted by Reena Ghorpade 6 years, 8 months ago

CBSE > Class 12 > Biology

1 answers

Manika Gupta 6 years, 8 months ago

The development of seed without fertilisstion is called apomix. It is a asexual reproduction that mimics sexual reproduction. ADVANTAGES → Development of seed is without fertilisation thus one can grow these plants in habitat where no pollinating agents are present i.e, does not depend on pollinating agents... DISADVANTAGE →Since the seed develop without fertilisation thus no variations will create.... →Continuity of undesirable characters →Seed generate from apomixis have less adaptability as compare due seed develop by fertilisation

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In any year pedigree related question ask in board examination

Posted by Saloni Maurya 6 years, 8 months ago

CBSE > Class 12 > Biology

1 answers

Yash Sharma 6 years, 8 months ago

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Ovary

Posted by Rishabh Yadav 6 years, 8 months ago

CBSE > Class 12 > Biology

2 answers

Aditya Dubey 6 years, 8 months ago

Overy is a female reproductive part which fuise with sperm to form zygote

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Pooja Thakur 6 years, 8 months ago

overy is a female reproductive part

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Which book is good for NEET ?

Posted by Veeresh Chinniu 6 years, 8 months ago

CBSE > Class 12 > Biology

4 answers

Ruchi Harariya 6 years, 8 months ago

I think pradeep and ncert both

0Thank You

Aditya Dubey 6 years, 8 months ago

You should read NCERT first

1Thank You

Kritika Dhingra 6 years, 8 months ago

Ncert and trueman's elementary

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∂Αяѕнαиαα ყα∂Αѵ ??? 6 years, 8 months ago

NCERT and pradeep

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What is the definition of parthenogenines

Posted by Shourya Yadav 6 years, 8 months ago

CBSE > Class 12 > Biology

0 answers

ANSWER

Similarity and difference between Apomixis and Parthenocarpy

Posted by Durgesh Kumar Yadav 6 years, 8 months ago

CBSE > Class 12 > Biology

1 answers

Lily ☺ 6 years, 8 months ago

Apomixis is seed formed without fertilisation. Parthenocarpy is fruit formed without fertilisation.

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ANSWER

What Is Coloustram

Posted by Ujjawal Yadav 6 years, 8 months ago

CBSE > Class 12 > Biology

3 answers

Ujjawal Yadav 6 years, 7 months ago

????thanks

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Aishwarya S 6 years, 8 months ago

It is the milk produced during first few days of lactation and is rich in immunoglobinA.

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Aakash Panchal 6 years, 8 months ago

It is a yellow colour fluid that contain IgA antibody it secrete during the period of lactation

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Function of calyxs and petals

Posted by Avinash Kumar Kumar 6 years, 8 months ago

CBSE > Class 12 > Biology

2 answers

Ranjna Tasshu 6 years, 8 months ago

They provide support to the flower

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Yogita Ingle 6 years, 8 months ago

Calyx: The calyx is the outermost whorl of the flower and is called sepals. Sepals looks like green leaves that are seen underneath the flower. Calyx may be gamosepalous (sepals united) or polysepalous (sepals free).

Petals: This layer lies just above the sepal layer. They are often bright in colour as their main function is to attract pollinators such as insects, butterflies etc to the flower.

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What does this statement means??briefly explain. "A typical angiosperm embryo sac,at maturity,though 8 nucleate is 7 celled."

Posted by Lavi Baliyan 6 years, 8 months ago

CBSE > Class 12 > Biology

1 answers

Mrutyunjay Khatua 6 years, 8 months ago

The embryo sac consist of 7cells...3 antipodal cell each with one nucleus in the chalazal end,one central cell with two nucleus called polar nucleus and two synergids each with one nucleus in the micropylar end and another egg cell with one nucleus.....This constitute 7cells and 8 nucleate stage.

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What is linkage and combination

Posted by Rahul Yadav 6 years, 8 months ago

CBSE > Class 12 > Biology

1 answers

Vinay Verma 6 years, 8 months ago

Capacity to link and combinate with other

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ANSWER

Incomplete dominance

Posted by Rahul Yadav 6 years, 8 months ago

CBSE > Class 12 > Biology

1 answers

∂Αяѕнαиαα ყα∂Αѵ ??? 6 years, 8 months ago

Incomplete dominance is the phenomenon of neither of the two alleles being dominant so that expression in the hybrid is a fine mixture or intermediate between the expressions of two alleles.

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Tassels of corn cob are?

Posted by Vashnavi Walia 6 years, 8 months ago

CBSE > Class 12 > Biology

1 answers

Sheetal Hooda 6 years, 8 months ago

Tassels of corn cob are the stigma and style which wave in wind to trap the pollen grains.

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Law of independent assortments

Posted by Rahul Yadav 6 years, 8 months ago

CBSE > Class 12 > Biology

1 answers

∂Αяѕнαиαα ყα∂Αѵ ??? 6 years, 8 months ago

The law states that when two pairs of traits are combined in a hybrid, segregation of one pair of characters is independent of the other pair of characters.

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Sperm release

Posted by Neeraj Thakur 5 years, 8 months ago

CBSE > Class 12 > Biology

1 answers

Lily ☺ 6 years, 8 months ago

Insemination

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Life spans of different animals?

Posted by Shaani Mathur 6 years, 8 months ago

CBSE > Class 12 > Biology

2 answers

Lily ☺ 6 years, 8 months ago

Elephant60-90 yrs Dog10-13yrs Cow20-25yrs horse60yrs

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Lavi Baliyan 6 years, 8 months ago

The period from birth to the natural death of an organism without any abnormalities k/as life span. It is different for different species.Examples are:Parrot(140yrs),Butterfly(1-2weeks),Dog(8yrs),etc.

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ANSWER

Name the enzyme present in Acrosome which helps in perination of ovum

Posted by Nirvana Sanyal 6 years, 8 months ago

CBSE > Class 12 > Biology

2 answers

Sunidhi Asthana 6 years, 8 months ago

Hydrolytic enzymes

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Yogita Ingle 6 years, 8 months ago

Acrosome is a cap-like structure present in the anterior part of the head of the sperm. It contains hyaluronidase enzyme, which hydrolyses the outer membrane of the egg, thereby helping the sperm to penetrate the egg at the time of fertilization.

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What is plasmotomy ? Give examples.

Posted by Prakriti Rao 6 years, 8 months ago

CBSE > Class 12 > Biology

1 answers

Yogita Ingle 6 years, 8 months ago

Plasmotomy : Plasmotomy is the division of a multinucleate protozoan into several small, multinucleate daughters without nuclear division. The daughters grow and regain the normal number of nuclei by nuclear divisions. It takes place in Opalina and Pelomyxa.

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What is implantation.. With suitable answer ??????

Posted by Anushka Sen?? 6 years, 8 months ago

CBSE > Class 12 > Biology

1 answers

Yogita Ingle 6 years, 8 months ago

The process of attachment of the blastocyst on the endometrium of the uterus is called implantation. Though the implantation may occur at any period between 6th and 10th day after the fertilization but generally it occurs on seventh day after fertilization.

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What are the diffrence between zoospores and zygote

Posted by Pratik Barasker 6 years, 8 months ago

CBSE > Class 12 > Biology

1 answers

Yogita Ingle 6 years, 8 months ago

Zoospore	Zygote
1.	A zoospore is a motile asexual spore that utilizes the flagella for movement.	A zygote is a non-motile diploid cell formed as a result of fertilization.
2.	It is an asexual reproductive structure.	It is formed as a result of sexual reproduction.

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Which mode of reproduction is facilitated by environment and why?

Posted by Niharika Kumari 6 years, 8 months ago

CBSE > Class 12 > Biology

2 answers

Niharika Kumari 6 years, 7 months ago

Ya i know it. But why

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Aakash Panchal 6 years, 8 months ago

Asexual reproduction

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Hello.... How sre pollen grains suored in pillen banks? State the purpose of storing pollen grains in these banks.

Posted by Lavanya ❤️? 6 years, 8 months ago

CBSE > Class 12 > Biology

2 answers

Lavanya ❤️? 6 years, 8 months ago

Thank u

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Aditya Raj 6 years, 8 months ago

Pollen grains stored in pollen banks in liquid nitrogen at -196'C . the purpose of storing is very helpful in later use in plant breeding programs.

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Hii guys......?? Both nucellus and endosperm have abundant reserve food material. How is their food reservior utilised in angiosperms?

Posted by Lavanya ❤️? 6 years, 8 months ago

CBSE > Class 12 > Biology

1 answers

Aditya Raj 6 years, 8 months ago

Nucellua give food to developing Embryosac. and Endosperm give food to developing Zygote.

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ANSWER

State the purposr for carrying emasculation in breeding experiments

Posted by Lavanya ❤️? 6 years, 8 months ago

CBSE > Class 12 > Biology

2 answers

Lavanya ❤️? 6 years, 8 months ago

Thank u

1Thank You

Harsh Pahuja 6 years, 8 months ago

In order to prevent stigma from self pollination and to reduce the chances of inbreeding depression or so that the stigma could be dusted by desired pollen

2Thank You

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