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Difference between viroid and bacteria

Posted by Priyanka Mishra 4 years, 6 months ago

1 answers

Sia ? 4 years, 6 months ago

Virus	Viroid
It is a nucleoprotein particle.	It is an RNA Particle.
Nucleic Acid can be DNA or RNA.	Viroid is formed of only RNA.
A protein covering of coat is present.	A protein coat is absent.
Virus has a larger size.	Viroid has a smaller size.
Virus infects all types of organisms.	Viroid infects only plants.

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Method of radioactive disposal is meeting stiff opposition from the public.why?

Posted by Priya Singh 7 years, 4 months ago

CBSE > Class 12 > Biology

2 answers

Ritu Singh 7 years, 4 months ago

Because the likage of radioactive substances can cause genetic disorders and in severe cases ,it can cause death of the population

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Lipak Mohapatra 7 years, 4 months ago

Radioactive disposal is meeting opposition due following reasons -It has worse impact on all speres on the environment. _ This includes environmental degradation in the form of biological manipulation, pollution etc _ Disposal of radioactive substances degrades the soil fertility which results in decrease in crop land. _it is affecting the food chain as it is responsible for the killing of several species of organisms. _it is responsible for genetic disorder in many organisms.

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How does dna finger printing helps in tracing evolutionary traces?

Posted by Lipak Mohapatra 7 years, 4 months ago

CBSE > Class 12 > Biology

0 answers

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What is shrews In brief account of evolution

Posted by Saumya Agrawal 7 years, 4 months ago

CBSE > Class 12 > Biology

1 answers

Hassanain Akram 7 years, 4 months ago

Shrew is the first mammal and very small animal.

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Who is the host of ascarise

Posted by Jasmine Singh 7 years, 4 months ago

CBSE > Class 12 > Biology

1 answers

Azmat Ali 7 years, 4 months ago

Small intestine

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Why children in slum areas having more immunity than childrens living in metro cities

Posted by Isha Ahuja 7 years, 4 months ago

CBSE > Class 12 > Biology

2 answers

Isha Ahuja 7 years, 4 months ago

Thnku☺

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Muskan Verma 7 years, 4 months ago

Children living in slum areas are more immunized against diseases because due to living in bad condition they r more liable to infect by diseases so their anti bodies formation takes place at that time and hence they resist by infection next timealso but in case of children living in metro cities their body is not habitual of any kind of infection so their immune system is not soo strong n thereby anti bodies does not respond against infections so that is the reason

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I need someones contact no

Posted by Shruti Mishra 7 years, 4 months ago

CBSE > Class 12 > Biology

1 answers

Shruti Mishra 7 years, 4 months ago

Plz

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What is the mechanism of the colpa moths in pollination?

Posted by Deven Bansal 7 years, 4 months ago

CBSE > Class 12 > Biology

0 answers

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trisomy has chromosome complement of

Posted by Rohit Pawar 7 years, 4 months ago

CBSE > Class 12 > Biology

0 answers

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Is ' pedigree analysis ' topic in board syllabus for session 2018-19 ?

Posted by Unknown Student 7 years, 4 months ago

CBSE > Class 12 > Biology

1 answers

Deven Bansal 7 years, 4 months ago

Yes

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Higher organisms have resorted to sexual reproduction in spite of its complexity. Why?

Posted by Unnati Verma. Unnati Verma. 7 years, 4 months ago

CBSE > Class 12 > Biology

1 answers

Kamal Maurya 7 years, 4 months ago

Due to variations and geen pool occur in sexual reproduction

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Why are offspring of oviparous animals at a greater risk as compared to offspring of viviparous animals?

Posted by Unnati Verma. Unnati Verma. 7 years, 4 months ago

CBSE > Class 12 > Biology

1 answers

Sakshee Kumari 7 years, 4 months ago

Because of predators threatning their survival upto adulthood

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Describe the post- fertilization changes in a flower.

Posted by Unnati Verma. Unnati Verma. 7 years, 4 months ago

CBSE > Class 12 > Biology

2 answers

Vishali Raina 7 years, 4 months ago

After fertilization ovary is converted into fruit ,ovules changes into seeds and other floral parts degenerate and fall off.

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Sweety Sweety 7 years, 4 months ago

Sepal ,petal fall down

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Define senescent phase.

Posted by Unnati Verma. Unnati Verma. 7 years, 4 months ago

CBSE > Class 12 > Biology

1 answers

Sakshee Kumari 7 years, 4 months ago

The time period from end of reproductive phase till death of an organism is known as senescent phase

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Define juvenile phase.

Posted by Unnati Verma. Unnati Verma. 7 years, 4 months ago

CBSE > Class 12 > Biology

1 answers

Sakshee Kumari 7 years, 4 months ago

Every organism has to reach a certain stage of growth and maturity before they can reproduce sexually. This period of growth and development is known as juvenile phase/vegetative phase.

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Define the external fertilization?

Posted by Unnati Verma. Unnati Verma. 7 years, 4 months ago

CBSE > Class 12 > Biology

1 answers

Hassanain Akram 7 years, 4 months ago

The fertilisation occur outside the body.

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Which is a better mode of reproduction: sexual or asexual? Why??

Posted by Unnati Verma. Unnati Verma. 7 years, 4 months ago

CBSE > Class 12 > Biology

1 answers

Hassanain Akram 7 years, 4 months ago

Sexual reproduction is better mode of reproduction bcz it brings variation which helps to survive in changing environment.

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What is vector

Posted by Bhupendar Ggy 7 years, 4 months ago

CBSE > Class 12 > Biology

2 answers

Lipak Mohapatra 7 years, 4 months ago

In biology vector is the agent that pathogen from infected to the host.

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Unnati Verma. Unnati Verma. 7 years, 4 months ago

Vector is a quantity having a direction as well as magnitude.

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Write the parasitic food chain

Posted by Ravi Yadav 7 years, 4 months ago

CBSE > Class 12 > Biology

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What are prions???

Posted by Aryan Rajput 7 years, 4 months ago

CBSE > Class 12 > Biology

1 answers

Unnati Verma. Unnati Verma. 7 years, 4 months ago

The word prion derived from proteinaceous infectious particle, it composed a prion protein are hypothesized as the cause of transmissible spongiform. It is also known as mad cow disease.

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Linkage and recombination

Posted by Mayank Kumar 7 years, 4 months ago

CBSE > Class 12 > Biology

3 answers

Sakshi Yadav 7 years, 4 months ago

Linkage is inversely proportional to recombination

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Pratibha Ydv 7 years, 4 months ago

Recombination= When two genes independently combines OR the combination of non- parental genes.

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Pratibha Ydv 7 years, 4 months ago

The physical association of two gene is known as linkage.

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why we use Cscl as a medium for centrifugation in experiment for semiconservative DNA replication

Posted by Dinesh Chandra 7 years, 4 months ago

CBSE > Class 12 > Biology

0 answers

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What is trait

Posted by Rajdeep Yadav 7 years, 4 months ago

CBSE > Class 12 > Biology

1 answers

Kiara Khurrana 7 years, 4 months ago

character

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From where does the bacteria for fermentation come???

Posted by Aryan Rajput 7 years, 4 months ago

CBSE > Class 12 > Biology

0 answers

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Which is a better mode of reproduction, sexual or asexual? why

Posted by Mohd Zain 7 years, 4 months ago

CBSE > Class 12 > Biology

3 answers

Hassanain Akram 7 years, 4 months ago

Sexual reproduction is btter bcz it brings variation which helps to survive in changing environment.

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Pratibha Ydv 7 years, 4 months ago

And in sexual reproduction variations occurs.which are necessary for evolution.

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Sakshi Yadav 7 years, 4 months ago

For evolution :- sexual reproduction which make an organism fit and help for survival as it is accepted by the nature

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How many types of heterozygous

Posted by Mojammil Alam 7 years, 4 months ago

CBSE > Class 12 > Biology

1 answers

Hassanain Akram 7 years, 4 months ago

Refers to the diploid organism when it contains two different alleles .

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Choli

Posted by Rahul Kumar 7 years, 4 months ago

CBSE > Class 12 > Biology

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What is the work FH hormone ?

Posted by Mohit Kunar 7 years, 4 months ago

CBSE > Class 12 > Biology

2 answers

Kavita Sharma 7 years, 4 months ago

And, in men fh acts on the sertoli cells of the testes to stimulate sperm production

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Kavita Sharma 7 years, 4 months ago

Fh hormone stimulate the growth of ovarian follicles in the ovary in women

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How does geitenogamy differ from xenogamy?

Posted by Monisha Raj Raj 7 years, 4 months ago

CBSE > Class 12 > Biology

2 answers

Siddharth Tripathi 7 years, 4 months ago

In geitenogamy pollen transfer from male to female flower on same plant.It is genetically self pollination but technically cross pollination. But xenogamy is technically and genetically cross pollination,beacuse pollen transfer from male flower of one plant to female flower another plant.

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Kiara Khurrana 7 years, 4 months ago

it is .......

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Which plant bears flower once in twelve years?

Posted by Siddharth Tripathi 7 years, 4 months ago

CBSE > Class 12 > Biology