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How can the scientific understanding of the menstrual cycle of human females help as a contraceptive measure?

Posted by Akhil Akku 6 years, 11 months ago

1 answers

Dev Joshi 6 years, 11 months ago

As the ovulation takes place in the mid of the menstrual cycle i.e. on 14th day. So the partners should avoid coitus in b/w 10-17th days of menstrual cycle. So with this scientific knowledge MC help as a Cont measure

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Drow a sectional view of human ovary and leable the different follicular stages. Ovum and corpus luteum.

Posted by Chaudhary Pankaj 6 years, 11 months ago

CBSE > Class 12 > Biology

1 answers

Navya Singh 6 years, 11 months ago

Refer to ncert

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In human female menstruation can be deferred by the administration of ?

Posted by Navneet Kumar 6 years, 11 months ago

CBSE > Class 12 > Biology

1 answers

Ishan Rana 6 years, 11 months ago

IUDs

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Cut pices of bryophyllum leves when put into wet soil produce new plant how?

Posted by Saurabh Bhandary 6 years, 11 months ago

CBSE > Class 12 > Biology

1 answers

Yogita Ingle 6 years, 11 months ago

In Bryophyllum, the leaf allows the development of many shoot buds. These buds form roots at their base. When these plantlets break and fall from the parent leaf on the ground, a new plant is formed. It is a type of vegetative propagation.

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How is oogenesis markedly different from spermatogenesis with respect to the growth till puberty in the humans?

Posted by Chaudhary Pankaj 6 years, 11 months ago

CBSE > Class 12 > Biology

1 answers

Harisha Goothy 6 years, 11 months ago

Oogenesis-this process stsrts at birth when millions of oogonia are formed and no more are formed after birth. Spermatogenesis-this process starts at puberty

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Assuming human genome as 3×10 to the power 9 bp , in how many base sequence would there be differences

Posted by Pushprajni Arya 6 years, 11 months ago

CBSE > Class 12 > Biology

1 answers

Prasu Biswas 4 years, 10 months ago

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Explain linkage and recombibation

Posted by Sriram Nivas 6 years, 11 months ago

CBSE > Class 12 > Biology

2 answers

Lakhan Bairwa 6 years, 11 months ago

And the occurance of progeny having cobination of traits different from the combination seen in the parents due to crossing over is called Recombination

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Lakhan Bairwa 5 years, 8 months ago

Linkage is the physical association of closely linked genes on a same chromosome. Linkage is inversely oriportional to cross over. When linkage increase cross over decrease and vice versa.

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What is Open and closed type lac operon?

Posted by Ritwik Talukdar 6 years, 11 months ago

CBSE > Class 12 > Biology

1 answers

Rohit Gupta 6 years, 11 months ago

on page 116 search the NCERT

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Name the hormones and their function which are secreted during different stages in female

Posted by Niharika Srivastav 6 years, 11 months ago

CBSE > Class 12 > Biology

1 answers

Ishan Rana 6 years, 11 months ago

O/estrogen(lh), progesterone(fsh),hcg,hpl,cortisol,relaxin,oxytocin

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Explain the different step involve in the secondary treatment of sewage

Posted by Naman Ghanshala 6 years, 11 months ago

CBSE > Class 12 > Biology

1 answers

Yogita Ingle 6 years, 11 months ago

Municipal sewage treatment involves the following steps:

1. Primary treatment/Physical treatment: It involves the removal of large and small particles from sewage. The floating debris is first removed by sequential filtration through wire mesh screens. Then, soil and smaller particles are removed by sedimentation in the settling tank. The sediment is called primary sludge and the supernatant is called effluent. The effluent is then sent for secondary treatment.

2. Secondary treatment/Biological treatment: Primary effluent is passed through large aeration tanks with constant mechanical agitation and air supply. Useful aerobic microbes grow rapidly and form flocs. The growing microbes consume organic matter and thereby, reduce the BOD of the effluent. After this, the effluent is passed into the settling tank. The bacterial flocs settle down and the sediment is now called activated sludge. A small part of the sludge is used as an inoculum in the aeration tank and the remaining part is passed into large tanks called anaerobic sludge digestors. In the digestors, heterotrophic microbes anaerobically digest bacteria and fungi in the sludge producing a mixture of gases such as methane, hydrogen sulphide and CO2 which form biogas.

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Define the fungi

Posted by Deepanshu Jaiswal 6 years, 11 months ago

CBSE > Class 12 > Biology

1 answers

Gaurav Seth 6 years, 11 months ago

Fungi (singular: fungus) are a group of eukaryotic living organisms that belong to the Kingdom Fungi. They are also known as the “death eater” because they consume dead and decaying matter. Fungi can be a single cellular organism like yeast or a multicellular organism such as mushrooms.

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What is gene therapy

Posted by Gaurav Kumar 6 years, 11 months ago

CBSE > Class 12 > Biology

1 answers

Pragya Gupta 6 years, 11 months ago

It is exprimental technique in which gene are tranferr to cure any desieas instead of drung use by doctor it help to curi problem of haemophilia and cyst fibrosis gene get inserted into the cell whre it neccesary

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Name any two vertebrate body part that homologous to human forelimbs

Posted by Deepak Kushwah 6 years, 11 months ago

CBSE > Class 12 > Biology

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Difference btw template and coding strand

Posted by Vishal Sharma 6 years, 11 months ago

CBSE > Class 12 > Biology

1 answers

Suresh Kumar Awasthi 6 years, 11 months ago

Template sequence 3'-5' .& coding sequence 5'-3'

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Metion any two significant role predation plays in nature

Posted by Deepak Kushwah 6 years, 11 months ago

CBSE > Class 12 > Biology

1 answers

Priyanka Singh 6 years, 11 months ago

● Maintains the food chain ● Keeps the organisms around it in discipline

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Difference between rape and coitus

Posted by Albert Richard 6 years, 11 months ago

CBSE > Class 12 > Biology

1 answers

Jayant Tehlan 6 years, 11 months ago

Every rape is coitus but every coitus is not rape

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difference between normal cells and cancer cells table

Posted by Zuha Hasan 6 years, 11 months ago

CBSE > Class 12 > Biology

1 answers

Shaina Khan 6 years, 11 months ago

Normal cell don't show metastatis but cancer cells show Normal cells have property of cell differentiation but cancer cells don't have Normal cells show contact inhibition but Cancer cell don't

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adaptive radiation is an example of covergent type or divergent type of evolution??

Posted by Ashwini Kumar Mohanty 6 years, 11 months ago

CBSE > Class 12 > Biology

1 answers

Dev Joshi 6 years, 11 months ago

Divergent

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What is evolution?

Posted by Saurabh Yaduvansi 6 years, 11 months ago

CBSE > Class 12 > Biology

2 answers

Dev Joshi 6 years, 11 months ago

Changes which occur in organism in along time on the basis of which habitat it is living and according to physical changes in that environment.

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Shaikh Umar 6 years, 11 months ago

Change which occur at very longer time is called evolution

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Cut piece of bryophyllum leaves when put into wet soil produce new plant how?

Posted by Yogesh Kumar 6 years, 11 months ago

CBSE > Class 12 > Biology

2 answers

Dev Joshi 6 years, 11 months ago

As leaves are vegetative propagules of bryophyllum

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Harisha Goothy 6 years, 11 months ago

Vegetative propagation...the cut piece acts like a propagule

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What Pest resistance plant

Posted by Gajendra Gangwar 6 years, 11 months ago

CBSE > Class 12 > Biology

1 answers

Mehak Gupta 6 years, 11 months ago

Pest resistant crops section Pest resistant GM crops (primarily cotton and maize), have been genetically modified so they are toxic to certain insects. They are often called Bt crops because the introduced genes were originally identified in a bacterial species called Bacillus thuringiensis. These bacteria produce a group of toxins called Cry toxins.

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Explaination on faraday law

Posted by Ayushi Prakash 6 years, 11 months ago

CBSE > Class 12 > Biology

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What is difference between asexual and sexual reproduction

Posted by Rohit Chandravnshi 6 years, 11 months ago

CBSE > Class 12 > Biology

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Difference Between monocot and dicot embryo?

Posted by Purusottam Singh 4 years, 6 months ago

CBSE > Class 12 > Biology

1 answers

Sia ? 4 years, 6 months ago

<div dir="ltr" style="text-align: left;" trbidi="on"> <div align="justify">Monocot Embryo</div> 1. Only one cotyledon attached to the embryonal axis.
2. Plumule is latral.
3. A single cotyledon occupies terminal position.
4. The envelope of plumule is called coleoptile.
5. Coleorrhiza is a protective sheath of radicle.
6. Suspensor comparatively larger.
7. A single cotyledon called scutellum is present.
Dicot Embryo
1. There are two cotyledons attached to an embryonal axis.
2. Plumule occur distally.
3. Cotyledons occur laterally.
4. Coleoptile absent.
5. Coleorrhiza absent.
6. Suspensor large.
7. Scutellum absent.</div>

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What is there in plants that forms spindle fibres at the time of cell division ?

Posted by Nenshu Nakrani 6 years, 11 months ago

CBSE > Class 12 > Biology

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When and how does placenta develop in human female

Posted by Imran Usmani 6 years, 11 months ago

CBSE > Class 12 > Biology

1 answers

Jayant Tehlan 6 years, 11 months ago

NCERT page-53 3.6

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In most of angiosperm pollen grains are shed in the two celled stage name the cell. Why are the cells different in size

Posted by Suresh Kumar Awasthi 6 years, 11 months ago

CBSE > Class 12 > Biology

1 answers

Isha Ahuja 6 years, 11 months ago

Vegetative cell and generative cell....vegetative cell is large and it has large irregular shaped nucleus while the generative cell is small and float in the cytoplasm of vegetative cell

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What is Amnicentesis?

Posted by Mohd Nasir Ansari Hussain 6 years, 11 months ago

CBSE > Class 12 > Biology