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What would be the molar concentration of human DNA in a human cell?

Posted by K@Łp@N@ $Øđh!?? 6 years, 6 months ago

CBSE > Class 12 > Biology

1 answers

Yogita Ingle 6 years, 5 months ago

The molar concentration of human DNA in a human diploid cell is as follows:

⇒ Total number of chromosomes × 6.023 × 10²³

⇒ 46 × 6.023 × 10²³

⇒ 2.77 ×10¹⁸ Moles

Hence, the molar concentration of DNA in each diploid cell in humans is 2.77 × 10²³ moles.

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Chapter 13 Self concentration of the sea measured in parts per thousand is Option (A) 10-15 optio(B) 30-70 Option(C) 0-5 Option(D) 30-35

Posted by Anita Lohiya 6 years, 6 months ago

CBSE > Class 12 > Biology

1 answers

Anita Lohiya 6 years, 6 months ago

Option(D)

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What is linkage?

Posted by Parul Singh 6 years, 6 months ago

CBSE > Class 12 > Biology

2 answers

Nishu Goyal 6 years, 6 months ago

Linkage is the tendency of genes to stay together and don't form recombination

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K@Łp@N@ $Øđh!?? 6 years, 6 months ago

Genetic linkage is the tendency of DNA sequences that are close together on a chromosome to be inherited together during the meiosis phase of sexual reproduction. Two genetic markers that are physically near to each other are unlikely to be separated onto different chromatids during chromosomal crossover, and are therefore said to be more linked than markers that are far apart. In other words, the nearer two genes are on a chromosome, the lower the chance of recombination between them, and the more likely they are to be inherited together. Markers on different chromosomes are perfectly unlinked. Genetic linkage is the most prominent exception to Gregor Mendel's Law of Independent Assortment. The first experiment to demonstrate linkage was carried out in 1905. At the time, the reason why certain traits tend to be inherited together was unknown. Later work revealed that genes are physical structures related by physical distance. The typical unit of genetic linkage is the centimorgan (cM). A distance of 1 cM between two markers means that the markers are separated to different chromosomes on average once per 100 meiotic product, thus once per 50 meioses.

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Wht is germ.cell

Posted by Priya Rani 6 years, 6 months ago

CBSE > Class 12 > Biology

2 answers

Naman Jain 6 years, 6 months ago

Germ cells are the reproductive cells which contains the half the number of chromosome..for example in case of male they are sperms and in case of females they are ovum or egg..

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Parul Singh 6 years, 6 months ago

Germ cell contains half number of chromosome of somantic cell. Germ cells are reproductive cell, egg cells in female and sperm cells in male.

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Sertoli cells are regulated by the pituitary hormone known as

Posted by Rr Rr 6 years, 6 months ago

CBSE > Class 12 > Biology

1 answers

Parul Singh 6 years, 6 months ago

FSH, because they line the seminiferous tubules in the testis and they protect spermatids and give nutrients to the developing mature spermatozoa.

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Types of questions related to the chapter EVOLUTION.

Posted by Rimali Das 6 years, 6 months ago

CBSE > Class 12 > Biology

1 answers

Arpita Tiwari 6 years, 6 months ago

There are several types of questions are.there like ..how ones theories are dissproved by other and questions telated to geological periods of plsnt snd vertebrates ..and thete are many more

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Which diagrams imp in inheritence chapter

Posted by Md Zubair Khan 6 years, 6 months ago

CBSE > Class 12 > Biology

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Sporogenous tissue

Posted by Saloni Narang 6 years, 6 months ago

CBSE > Class 12 > Biology

1 answers

K@Łp@N@ $Øđh!?? 6 years, 6 months ago

Sporogenous cells are those cells which are capable of undergoing meiotic divisions. These cells combine with each other to form a sporogenous tissue.

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Can anyone help me in making the investigatory project of biology on topic evolution..pleasee

Posted by Alisha Jajodia 6 years, 6 months ago

CBSE > Class 12 > Biology

3 answers

Alisha Jajodia 6 years, 3 months ago

Whole topic

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Alisha Jajodia 6 years, 6 months ago

Whole topic evolution

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Parul Singh 6 years, 6 months ago

Do u have a particular topic in evolution or u have taken the whole evolution??

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How many true breading varieties of garden pea did Mendel selected for starting his genetic experiment

Posted by Anisha Rai 6 years, 6 months ago

CBSE > Class 12 > Biology

3 answers

Vyshnavi T P 6 years, 6 months ago

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Vivek Kumar 6 years, 6 months ago

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Anisha Rai 6 years, 6 months ago

Answer

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What is Agrobacterium mediated genetic transformation described as natural genetic engineer in plants

Posted by Tannu Prajapati 6 years, 6 months ago

CBSE > Class 12 > Biology

1 answers

Nishu Goyal 6 years, 6 months ago

Because of its ability to transfer gene without human interfare so it is called natural genetic engineer

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What is saltation in de vries??

Posted by Alisha Jajodia 6 years, 6 months ago

CBSE > Class 12 > Biology

3 answers

Shudhanshu Ranjan 6 years, 6 months ago

Single cell large mutation

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Arpita Tiwari 6 years, 6 months ago

Mutation cause speciation that is known as saltation

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Sneh Deswal 6 years, 6 months ago

It is sudden and large mutational change from one gen. to the next gen

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What is Immune system

Posted by Priyanshi Yadav 6 years, 6 months ago

CBSE > Class 12 > Biology

2 answers

Arpita Tiwari 6 years, 6 months ago

the ability of a body to fight against disease causing agentsare called immune system

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Sneh Deswal 6 years, 6 months ago

Immune system is the defense mechanism of the body against disease causing pathogens or any foreign invader entering the body

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Organic farmers prefer biological control of diseases and pests to the use of chemicals for the same purpose. Justify

Posted by Vishal Desai 6 years, 6 months ago

CBSE > Class 12 > Biology

1 answers

Nishu Goyal 6 years, 6 months ago

Because organic farming is friendly to environment. It protect plants ,soil,water bodies from contamination and also have good effect on human health

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Name the genes of the crops imported to India . Which crop varieties were produced as a result of anther culture at different places of the world?

Posted by Sidhu Sukhmander 6 years, 6 months ago

CBSE > Class 12 > Biology

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What is typhoid

Posted by Vishun Dayal 6 years, 6 months ago

CBSE > Class 12 > Biology

5 answers

Arpita Tiwari 6 years, 6 months ago

Typhoid is a pathogenic bacterium disease

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K@Łp@N@ $Øđh!?? 6 years, 6 months ago

OVERVIEW SYMPTOMS TREATMENTS SPECIALISTS 1 of 4 Typhoid fever is an infection that spreads through contaminated food and water. Vaccines are recommended in areas where typhoid fever is common. Very rare Fewer than 100 thousand cases per year (India) Partly preventable by vaccine Treatable by a medical professional Spreads through contaminated food or water Requires a medical diagnosis Lab tests or imaging often required Short-term: resolves within days to weeks HOW IT SPREADS Through contaminated food or water.

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Aarushi Singh 6 years, 6 months ago

Typhoid is a disease that affects the body especially it's virus attacks the small intestine and it's symptoms include constant high fever, stomach pain. It's virus name is salmonella typhi. It was first discovered by a cook named Mary Mallon... Hope it helps you.....??

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Sneh Deswal 6 years, 6 months ago

Typhoid is a disease having symptoms like constant grade fever , etc caused by a bacteria ( Salmonella typhi) and spread through contaiminated food and water

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Alisha Jajodia 6 years, 6 months ago

Typhoid is an infectious disease which is caused by salmonella typhi.

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What is dna and how it is formed

Posted by Dheeraj Prajapati 6 years, 6 months ago

CBSE > Class 12 > Biology

2 answers

K@Łp@N@ $Øđh!?? 6 years, 6 months ago

DNA is made up of molecules called nucleotides. ... Another type of nucleic acid, ribonucleic acid, or RNA, translates genetic information from DNA into proteins. Nucleotides are attached together to form two long strands that spiral to create a structure called a double helix.

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Aarushi Singh 6 years, 6 months ago

DNA(Deoxy ribo nucleic acid ) is a genetic material that is inherited from parents and it is called helix model. It is made of Nucleic acids, phosphate group and ribose sugar.

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Why do we dream??

Posted by Rajput Boy 6 years, 6 months ago

CBSE > Class 12 > Biology

2 answers

Rajput Boy 6 years, 6 months ago

What is the reason or purpose?

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Arpita Tiwari 6 years, 6 months ago

Becoz of activeness of sub conscious mind

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What is working of salt briadge

Posted by Sahil Srivastava 6 years, 6 months ago

CBSE > Class 12 > Biology

2 answers

Nishu Goyal 6 years, 6 months ago

Complete the circut so that flow of electron and current can take place it also provide neutrality to circut so that it can work continuously.

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Sanjay Choudary 6 years, 6 months ago

Conductance of electrons...

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2009 question solutions of cbse board

Posted by Prabhat Sahu 6 years, 6 months ago

CBSE > Class 12 > Biology

0 answers

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What is term mathu

Posted by Ashiq Ashiq 6 years, 6 months ago

CBSE > Class 12 > Biology

0 answers

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Breathing nd exchange of gases

Posted by Komal Puri 6 years, 6 months ago

CBSE > Class 12 > Biology

1 answers

Meghna Thapar 5 years, 8 months ago

The mechanism by which an organism obtains oxygen from the air and releases carbon dioxide is called breathing.

The respiration takes place inside the cells of the body so it is known as cellular respiration. The energy released during cellular respiration is immediately used to synthesize a molecule called ATP which is used to fuel all other activities in the cell. In these processes, ATP is broken down giving rise to a fixed amount of energy which can drive the endothermic reactions taking place in the cell.

Diffusion is insufficient to meet the oxygen requirements of large multicellular organisms like humans because the volume of the human body is so big that the oxygen cannot diffuse into all the cells of the human body quickly and oxygen will have to travel large distances to reach each and every cell of the body.

Large organisms contain a respiratory pigment called haemoglobin which carries the oxygen from the lungs to all the body cells very efficiently.
A terrestrial animal has an advantage over an aquatic animal in regard to obtaining oxygen for respiration that it is surrounded by an oxygen rich atmosphere from where it can take any amount of oxygen.

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Is ch 5 in biology important ?or not..

Posted by Sakshi Kaur ? 6 years, 6 months ago

CBSE > Class 12 > Biology