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Why r prokaryotes not given any number regarding threir biodiversity

Posted by Mohit Sepat 7 years, 2 months ago

CBSE > Class 12 > Biology

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Why are exonuclease not useful in genetic engineering

Posted by Mohit Sepat 7 years, 2 months ago

CBSE > Class 12 > Biology

1 answers

Priyanka Singh 7 years, 2 months ago

Since exonuclease can cut the DNA from the ends only therefore it is not useful

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Mention any two aspects of primary productivity

Posted by Mohit Sepat 7 years, 2 months ago

CBSE > Class 12 > Biology

1 answers

Yogita Ingle 7 years, 2 months ago

The primary productivity has two aspects as discussed below:
Gross Primary Productivity (GPP) : It is the rate of production of organic matter during photosynthesis. A considerable amount of GPP is utilised by plants in respiration. .
Net Primary Productivity (NPP): It is the available biomass for the consumption by heterotrophs (herbivores and decomposers). It is actually the amount of energy left in the producers after utilisation of some energy during respiration. Thus, Gross Primary Productivity minus the Respiration Losses gives the Net Primary Productivity.
GPP - R = NPP
where, R = Respiration losses.

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Mention any three phenomenon that prevent autogamy and geinotogamy but endure xenogamy

Posted by Mohit Sepat 7 years, 2 months ago

CBSE > Class 12 > Biology

1 answers

Priyanka Singh 7 years, 2 months ago

● Production of unisexual flowers (dioecy) ● Self incompatibility ● Bagging ● Emasculation

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How is innate immunuty different from immunity acqiired through vaccination ??

Posted by Mohit Sepat 7 years, 2 months ago

CBSE > Class 12 > Biology

1 answers

Priyanka Singh 7 years, 2 months ago

Innate immunity is present inside a human life long wheras acquired immunity through vaccination is present for a short period of time.

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Advise any project for biology

Posted by Ajay Raj 7 years, 2 months ago

CBSE > Class 12 > Biology

1 answers

Komal Dhingra 7 years, 2 months ago

1 DNA 2 applications of biotechnology 3 reproductive health

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What type of fertility occur in tapeworm and earthworm?

Posted by Ammu Gill 7 years, 2 months ago

CBSE > Class 12 > Biology

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What type of fertilization occurs in tapeworm and earthworm ?

Posted by Agrit Garg 7 years, 2 months ago

CBSE > Class 12 > Biology

0 answers

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what is spearmiogenesis?

Posted by Ritwik Talukdar 7 years, 2 months ago

CBSE > Class 12 > Biology

1 answers

Yogita Ingle 7 years, 2 months ago

Spermiogenesis-

The spermatids are transformed into sperms, also called as spermatozoa by the process called spermiogenesis.
After spermiogenesis, sperm heads become embedded in the Sertoli cells and are released from the seminiferous tubules by the process called spermiation

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Difference between spermatogenesis and ogenesis

Posted by Manish Kumar 7 years, 2 months ago

CBSE > Class 12 > Biology

1 answers

Tikishree Menaka Murmu 7 years, 2 months ago

Spermatogenesis occurs in male and ogenesis occurs in females reproductive system.

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What is multifactorial inheritance?

Posted by Shivani .. 7 years, 2 months ago

CBSE > Class 12 > Biology

1 answers

Yogita Ingle 7 years, 2 months ago

Multifactorial inheritance means that many factors (multifactorial) are involved in causing a birth defect. The factors are usually both genetic and environmental where a combination of genes from both parents, in addition to unknown environmental factors, produce the trait or condition.

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Explain PCR technique

Posted by Pushpanjali Kumari 7 years, 2 months ago

CBSE > Class 12 > Biology

1 answers

Harish Chhillar 7 years, 2 months ago

Multiple copies of gene or dna chemically synthesized invitro

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Difference between VNTR and probe

Posted by Mehul Sharma 7 years, 2 months ago

CBSE > Class 12 > Biology

1 answers

Surabhi Tiwari 7 years, 2 months ago

VNTR:- ( variable number tandem repeat) is a short nucleotide sequence located in 5he genome and organized as the tandem repeat on that location. Probe:- It is a short sequence of DNA and RNA of variable length which is used to detect the presence of particular nucleotide sequence in DNA or RNA samples that is complementary to the sequence.

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Role of PCR in molecular diagnosis

Posted by Sazzad Yusuf 7 years, 2 months ago

CBSE > Class 12 > Biology

2 answers

Krishna Garg 7 years, 2 months ago

Sorry its pathogen not patogen

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Krishna Garg 7 years, 2 months ago

PCR molecules helps in amplification of nucleic acid of patogen by PCR for its detection. Ex. Used for detection of HIV in suspected AIDS patients.

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Diapause

Posted by Harish Chhillar 7 years, 2 months ago

CBSE > Class 12 > Biology

3 answers

Sanu Singh 7 years, 2 months ago

In diapause, the metabolic rate of the organism exteamly slows down to manage with the stressfull conditions.

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Arushi Dogra 7 years, 2 months ago

Suspended development of an organism during unfavourable condition....eg monarch butterfly and zooplankton.

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Vishali Raina 7 years, 2 months ago

Diapause is a state of suspended development to cope up with unfavourable conditions.

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Draw suture of pBR322?

Posted by Khelan (Khellu) 7 years, 2 months ago

CBSE > Class 12 > Biology

1 answers

Vishali Raina 7 years, 2 months ago

Refer ncert pg no.199

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How does virus infected cells provide innate immunity to healthy cells?

Posted by Vishali Raina 7 years, 2 months ago

CBSE > Class 12 > Biology

1 answers

Harish Chhillar 7 years, 2 months ago

By proteins called interferons

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Describe BOD?

Posted by Radhey Patel 7 years, 2 months ago

CBSE > Class 12 > Biology

1 answers

Yogita Ingle 7 years, 2 months ago

BOD refers to the amount of oxygen that would be consumed if all the organic matter in one litre of water were oxidised by bacteria. The microbes biodegrade the major part of the organic matter in the effluent by using the dissolved oxygen. It reduces the BOD of the effluent. When the BOD of sewage is reduced significantly the effluent is passed into a settling tank where the bacterial floes are allowed to sediment forming the activated sludge. Thus, higher the value of BOD, more is the water polluted and more is the amount of biodegradable matter.

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Ectopic pregnancies

Posted by Ritik Kataria 7 years, 2 months ago

CBSE > Class 12 > Biology

2 answers

Arushi Dogra 7 years, 2 months ago

Implantation of embryo in the reproductive system other than uterus.

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Pallavi Choubey 7 years, 2 months ago

A pregnancy in which fertilised egg implants outside the uterus.

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Why reproduction is essential

Posted by Lalan Kumar 7 years, 2 months ago

CBSE > Class 12 > Biology

2 answers

Krishna Garg 7 years, 2 months ago

1. Reproduction is necessary for the cotinuity of the species. 2. Sexual repreduction is responsible for variation in a plpulation and its inheritance to future generation

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Tikishree Menaka Murmu 7 years, 2 months ago

Reproduction is fundamental features of all living organisms. And it is also a biological process by which living organisms produces new offspring similar to them. And ensures continuity of various species of earth ?............ So it is essential.

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We know 99.9% of dena sequence is same in human . If we hv 3×10^9 bp then what ll be that different 0.1%bp

Posted by Nitesh Jangra 7 years, 2 months ago

CBSE > Class 12 > Biology

0 answers

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Mention the chemicals released from mast cells during an allergic reaction ?

Posted by Pooja Choudhary 7 years, 2 months ago

CBSE > Class 12 > Biology

2 answers

Kumud Seth 7 years, 2 months ago

Histamine and serotonin

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Sanjay Dahiya 7 years, 2 months ago

May be antihistamine

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What is the role of C-peptide in human insulin?

Posted by Rahul Vishwakarma 7 years, 2 months ago

CBSE > Class 12 > Biology

2 answers

Arushi Dogra 7 years, 2 months ago

C peptide is an extra stretch....that inactivates the insulin...called as pro insulin

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Tikishree Menaka Murmu 7 years, 2 months ago

The C-peptide of proinsulin is important for biosynthesis of insulin.

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What is cytoplasm?

Posted by Kanhaiya Singh 7 years, 2 months ago

CBSE > Class 12 > Biology

1 answers

Rishabh Goyal 7 years, 2 months ago

the material that a cell is made of, except for the nucleus

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What happen if corpous luteum is not degenerated

Posted by Anurag Malik 7 years, 2 months ago

CBSE > Class 12 > Biology

1 answers

Yogita Ingle 7 years, 2 months ago

The corpus luteum is a temporary endocrine structure in female ovaries that is involved in the production of relatively high levels of progesterone and moderate levels of estradiol and inhibin A.its function The corpus luteum is essential for establishing and maintaining pregnancy in females. The corpus luteum secretes progesterone, which is a steroid hormone responsible for the decidualization of the endometrium (its development) and maintenance, respectively.

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what are alpha beta and gamma biodiversity??

Posted by Shaima Ameen 7 years, 2 months ago

CBSE > Class 12 > Biology

1 answers

Yogita Ingle 7 years, 2 months ago

Alpha diversity refers to the average species diversity in a habitat or specific area. Alpha diversity is a local measure.

Beta diversity refers to the ratio between local or alpha diversity and regional diversity. This is the diversity of species between two habitats or regions. It is calculated by the following equation:

Gamma diversity is the total diversity of a landscape and is a combination of both alpha and beta diversity.

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Difference between test cross and back cross ?

Posted by Amreen Fatma 7 years, 2 months ago

CBSE > Class 12 > Biology

1 answers

Yogita Ingle 7 years, 2 months ago

Backcross is a cross of a hybrid (F1) with any one of its parents, in order to achieve offspring with a genetic identity which is closer to that of the parent. It is used in horticulture, animal breeding and in production of gene knockout organisms.

Test cross is a cross between an organism whose genotype for a certain trait is unknown and an organism that is homozygous recessive for that trait so the unknown genotype can be determined from that of the offspring. This cross is used to determine whether the individual in question is heterozygous or homozygous for a certain allele. It can also used as a method to test for linkage, i.e. to estimate recombination fraction.

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Topoisomerase second name?

Posted by Radhey Patel 7 years, 2 months ago

CBSE > Class 12 > Biology