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If two sperm fuses ovum at the same time, then what is the result?

Posted by Shris - 6 years, 7 months ago

5 answers

Gursharn Kaur 6 years, 7 months ago

When 1 sperm enters the ovum. The acrosomal end proceeds some reactions. These reactions doesn't allow the another sperm to fuse and fertilise the ovum

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Sudarshan Sharma 6 years, 7 months ago

May be conjoint twins are formed

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Rishabh Soni 6 years, 7 months ago

Two sperm can't fuse on same time

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Souromi Chatterjee 6 years, 7 months ago

Two sperms do not fuses ovum at one time.. only one sperm enters the ovum amd cortical and acrosomal reactions after one sperm enters the ovum ensures monospermy and prevents polyspermy

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Divyansh Mishra 6 years, 7 months ago

twins are formed which are not identical

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in single celled organism there is no natural death why?

Posted by Himanshu Raj 6 years, 7 months ago

CBSE > Class 12 > Biology

5 answers

Rafi Zamir 6 years, 7 months ago

Because they are immortal

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Adarsh Suresh 6 years, 7 months ago

Because of. Clone. Genetically. And morphology similar

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Antriksh Bohara 6 years, 7 months ago

it is due the fact that they divide and continue to live as thier daughter cells

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Sia Mourya 6 years, 7 months ago

I think u should study NCERT first.

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Ujjawal Yadav 6 years, 7 months ago

Bcoz they Will Divide And Form An Other Individuals

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briefly explain the structure of a typical dicotyledons enbryo

Posted by Preethi Preethi 6 years, 7 months ago

CBSE > Class 12 > Biology

1 answers

Meghna Thapar 5 years, 5 months ago

Parts of typical dicot embryo includes- Plumule, cotyledons, hypocotyl, radical and root cap.

A typical dicotyledonous embryo, consists of an embryonal axis and two cotyledons.
The portion of embryonal axis above the level of cotyledons is the epicotyl, which terminates with the plumule or stem tip.
The cylindrical portion below the level of cotyledons is hypocotyl that terminates at its lower end in the radical or root tip.
The root tip is covered with a root cap.

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what is Phenocopy

Posted by Avinash Singh 6 years, 7 months ago

CBSE > Class 12 > Biology

4 answers

Rafi Zamir 6 years, 7 months ago

Partnenocarpy is the method of developing an fruit without fertilisation

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Adarsh Suresh 6 years, 7 months ago

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Gayatri Devi 6 years, 7 months ago

Can you tell me this question is from which chapter

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Avinash Singh 6 years, 7 months ago

The nonheriditary phenotype features caused by environment is called phenocopy

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Natural dye litmus is obtained from which species of roccella?

Posted by Monika Thakur 6 years, 7 months ago

CBSE > Class 12 > Biology

2 answers

Monika Thakur 6 years, 7 months ago

From Rocella monotegnia can we obtain litmus?

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Gaurav Seth 6 years, 7 months ago

Roccella tinctoria is a lichenised species of fungus in the genus Roccella

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Fertilization of animals

Posted by Sivnath Yasav 6 years, 7 months ago

CBSE > Class 12 > Biology

0 answers

ANSWER

A plant having genotype rrYy produce 2000gamates then how many gamates are of genotype rY

Posted by Sataybir Sataybir 6 years, 7 months ago

CBSE > Class 12 > Biology

0 answers

ANSWER

A plant with genotype RrYy produce 2000 gamates then how many gamates are of genotype rY.

Posted by Sataybir Sataybir 6 years, 7 months ago

CBSE > Class 12 > Biology

0 answers

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What will be the total number of gamates produced by a plant with genotype AaBbCcDd?

Posted by Sataybir Sataybir 6 years, 7 months ago

CBSE > Class 12 > Biology

0 answers

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What will be the dihybrid ratio for a cross between HHTT with hhtt

Posted by Sataybir Sataybir 6 years, 7 months ago

CBSE > Class 12 > Biology

1 answers

Sinchana Malagond 6 years, 7 months ago

Same as roundyellow and green wrinkled seeds 9:3:3:1

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In a cross between a pure round yellow seeded plant, how many plants are produced in F2 out of 16 which are homozygous for another?

Posted by Sataybir Sataybir 6 years, 7 months ago

CBSE > Class 12 > Biology

1 answers

Sinchana Malagond 6 years, 7 months ago

Only 4 i.e., 2 parental types and 2 recombinants are homozygous for each other kindly refer ncert textbook pg no. 79

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Which type of paper pattern is coming in the 2019 -2020 board exam

Posted by Nikita Singh 6 years, 7 months ago

CBSE > Class 12 > Biology

1 answers

Souromi Chatterjee 6 years, 7 months ago

Dont know about the full paper.. but as reported by some of my tuition teachers nd school teachers 20 short answers will come for 20 marks... this is applicable for all subjects

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Mention any two conditions that enhance the change of syngamy in organisms exhibiting external fertilization?

Posted by Chungpi Thangzom 6 years, 7 months ago

CBSE > Class 12 > Biology

0 answers

ANSWER

A woman with b blood group married a man with a blood group , they had 2 sons nd both had o group show the possibility of such inheritance list allels that involved in determining the blood group?

Posted by Arman Sidhu 6 years, 7 months ago

CBSE > Class 12 > Biology

0 answers

ANSWER

Explain the monohybrid cross between tall and dwarf plant

Posted by Himani Dange 6 years, 7 months ago

CBSE > Class 12 > Biology

1 answers

G R 6 years, 7 months ago

TT ×tt Tt - selfing. F1 TT, Tt ,Tt , tt- F2

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Can you suggest some good books for Neet preparation 2020 for biology n other subjects

Posted by Sinchana Malagond 6 years, 7 months ago

CBSE > Class 12 > Biology

4 answers

Mayank Aggarwal 6 years, 7 months ago

NCERT BIOLOGY. (IMPORTANT) PRADEEP BIOLOGY ELEMENTRY BIOLOGY NCERT PHYSICS SL ARORA PHYSICS NCERT CHEMISTRY PRADEEP CHEMISTRY DINESH COMPANION CHEMISTRY

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Souromi Chatterjee 6 years, 7 months ago

U can opt arihant NEET series for physics chemitry nd bio... its available in two volumes one for 11 and other for 12.. truemans series can also be followed.. and even mtg dinesh comprehensive can help

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Sinchana Malagond 6 years, 7 months ago

Books ka naam bataao

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Rds 4141 6 years, 7 months ago

You may go to a good book shop to buy books and otherwise you can subscribe claderig yt

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Ifi got written in cbse result that ft in bio and ft in chemistry so in which i have to prepare for compartment exam

Posted by Manish Kumar 6 years, 7 months ago

CBSE > Class 12 > Biology

0 answers

ANSWER

How to study for compartment exam for pass in ncrt

Posted by Manish Kumar 6 years, 7 months ago

CBSE > Class 12 > Biology

0 answers

ANSWER

Name the cell and explain the process it undergoes to develop into an embryo sac

Posted by Sanjeev Ahlawat 6 years, 7 months ago

CBSE > Class 12 > Biology

0 answers

ANSWER

how does penicillium reproduce sexually

Posted by Lrojo Longman 6 years, 7 months ago

CBSE > Class 12 > Biology

2 answers

Jagritee Jaiswal 6 years, 7 months ago

Penicillium cant reproduce sexually because doesnt involve gamates .

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Gaurav Seth 6 years, 7 months ago

Penicillum reproduces asexually by spore formation, through conidiospores.

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What is PLEIOTROPY?

Posted by Vikash Rajput 6 years, 7 months ago

CBSE > Class 12 > Biology

2 answers

Siddhartha Rastogi 6 years, 7 months ago

One Gene multiple effects

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Sinchana Malagond 6 years, 7 months ago

It's a condition in which a single gene is responsible for multiple phenotype expression in an organism example phenylketonuria

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a child has blood group O. if the father has blood group A and mother has blood group B. workout the genotype of the parents and genotype of the offspring.

Posted by Dikshita Baruah 6 years, 7 months ago

CBSE > Class 12 > Biology

1 answers

Shagun Mehan 6 years, 7 months ago

Sooo easy Father : A,O Mother : B,O Child : O,O

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How long does you it take

Posted by Madhvi Rana 6 years, 7 months ago

CBSE > Class 12 > Biology

0 answers

ANSWER

What is sporogenesia

Posted by Madhvi Rana 6 years, 7 months ago

CBSE > Class 12 > Biology

1 answers

Puneet And Lovish Biology Tutorials 6 years, 7 months ago

It is the process by which differentiated male germ cells called primary spermacytes undergo mieotic division to forms sperms by undergoing sequential steps is called sporogenesis

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What is ploidy

Posted by Gagan Verma 6 years, 7 months ago

CBSE > Class 12 > Biology

2 answers

Jagritee Jaiswal 6 years, 7 months ago

Ploidy is defined as the organism is diploid or haploid nature .

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Avantika Tayal 6 years, 7 months ago

Ploigy is basucally a feature of organism of its cells.it includes whethrer the organism is diploid that is 2n no. Of chromozomes of haploid i.e n no.of chromozomes.

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What is blastocyst

Posted by Ashish Kumar 6 years, 7 months ago

CBSE > Class 12 > Biology

2 answers

Yogita Ingle 6 years, 7 months ago

Blastocyst is formed after 4 to 5 days of fertilisation. A cavity is formed within the ball of cells of morula stage. Now blastocyst comprises of outer layer of cells and an inner mass of cells separated by fluid filled cavity called as blastocoel. Outer layer of cells is called as trophoblast and gives rise to placenta whereas inner cell mass gives rise to head, body and important structures of the foetus.

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Sinchana Malagond 6 years, 7 months ago

blastocyst in structure form in the early stages of mammals which further gives rise to gastrula kindly refer NCERT textbook

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Name and explain the role of inner and middle walls of human uterus?

Posted by Kiran Gautam 6 years, 7 months ago

CBSE > Class 12 > Biology

2 answers

Jagritee Jaiswal 6 years, 7 months ago

Inner wall-endometrium wall is help cyclic changes as menstrual cycle foetus growth amd help in implantation . Middle -myometrium wall hepl contraction during parturation .

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Gaurav Seth 6 years, 7 months ago

Inner- Endometrium supports foetal growth, helps in placenta formation after implantation.
Middle- Myometrium exhibits strong contraction during delivery of baby.

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A,B,D are 3 independing assorting gene their recessive alleles a,b,d respe tively A cross was made btwen them as Aa,bb,Dd genotype ,with aa,bb,dd.find out the genotype of offsprings produced

Posted by Tripti Kukreti 6 years, 7 months ago

CBSE > Class 12 > Biology

0 answers

ANSWER

what is pollunation

Posted by Kishan Kumar 6 years, 7 months ago

CBSE > Class 12 > Biology

2 answers

Aysha Enami 6 years, 7 months ago

Transfer pollengrain from anther to stigma is called pollination. The medium through which pollination occurs are called agents of pollination. For example water, wind, Insects

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Ashish Kumar 6 years, 7 months ago

The releasing of pollen grains in air and water to the anther is called pollination.

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Where does the sporopollenin present ? Mention its function.

Posted by Aditi Pandey 6 years, 7 months ago

CBSE > Class 12 > Biology

3 answers

Aysha Enami 6 years, 7 months ago

The exine of pollengrain is covered by sporollenin it is hardest substance. It protect pollengrain from harsh environment.

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Sunidhi Asthana 6 years, 7 months ago

The exine of pollen grain is made of sporopollenin it is very tough and hard layer.it prevent the pollen grain from the outside foreign materials which may be harmful for it..

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Shivam Jaiswal 6 years, 7 months ago

Pollen grain Protection Fossils of pollemgrain also contain sporopolenin

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