Posts from the ‘Miscellaneous’ Category

CLASS XII -UNIT TEST 2- BIOLOGY-QUESTION PAPER

KENDRIYA VIDYALAYA B.S.F DABLA

CLASS XII SC.    II-TERM UNIT TEST

Duration : 90 Mins                     Sub: Biology                 Max Marks : 40

General Instructions:

(i) All questions are compulsory.

(ii) The question paper consists of two sections A and B. Section A contains 6 questions of 5Marks each and Section B is of 10 questions of 1mark each.

Section  A

  1. a) Explain the observations of Meselson and Stahl when :-

(i) they cultured E. coli in a medium containing  15NH4Cl  for a few generations and centrifuged the content.

(ii) they transferred one such bacterium to the normal medium of  NH4Cl.

(b) What does the above experiment prove?

(c) Which is the first genetic material identified?

  1. (i) How and at what stage does Plasmodium enter into a human body?

(ii) With the help of a flow-chart, only show the stages of asexual reproduction in the life cycle of the parasite in the infected human.

(iii) Why does the victim show symptoms of high fever?

  1. Explain Hershey-Chase experiment. What was proved through this experiment?
  2. (a) A true breeding pea plant, homozygous for inflated green pods is crossed with another pea plant with constricted yellow pods (ffgg). What would be the phenotype and genotype of F1 and F2 generations? Give the phenotype ratio of F2 generation.

(b) State the generalisation proposed by Mendel on the basis of the above mentioned cross.

  1. (a)One of the codons on mRNA is AUG. Draw the structure of tRNA adapter molecule for this codon. Explain the uniqueness of this tRNA.

(b) Explain the process of charging of tRNA. Why is it essential in translation?

  1. Study the given pedigree chart and answer the questions that follow:

DIAGRAM IS NOT AVAILABLE

(a) Is the trait recessive or dominant?

(b) Is the trait sex-linked or autosomal?

(c) Give the genotypes of the parents shown in generation I and their third child shown in generation II and the first grandchild shown in generation III.

Section  B

  1. Name the two types of cells in which the HIV multiplies after gaining entry into the human body.
  2. Why do sports persons often fall victim to cocaine addiction?
  3. What is the economic value of Spirulina?
  4. What was the speciality of the milk produced by the transgenic cow Rosie?
  5. How do neutrophils act as a cellular barrier to pathogens in humans?
  6. Suggest any two techniques which can help in early detection of bacterial viral infections much before the symptoms appear in the body.
  7. Name the type of immunity that is present at the time of birth in humans.
  8. Which of the following is the semi-dwarf wheat that is high yielding and disease resistant?

Pusa Shubra,    Kalyan Sona,     Ratna.

  1. Why are the plants produced by rnicropropagation called somaclones?
  2. Name the technique by which healthy plants can be recovered from the diseased plants.
Advertisements

Happeeeeeeeeee Earth Day…………

HappyEarthDay

Service to Others

Source of Inspiration

a1e9eed6bb4b559055d7a7a6a1bea68d

Helping others
can be a trap.
It can make us feel
superior
in control
self-righteous

Paradox, for helping
others also is a path
of Light to help us
grow, to learn compassion,
how to give love
without expectation.

Step carefully, Dear Ones,
that your acts of kindness
are of the purest intention.
Let our Creator
guide you in all you do.

View original post

Knock! Knock!

With Kisses And Hugs, Mom

wLSLCfg

Dear Gretel,

Yesterday morning, you were “sick“.

You coughed and coughed and sneezed and coughed some more.

You did this whole whiny-grouchy-sicky thing…

and Daddy and I agreed you should stay home from school.

Well…

at around 11 AM, I received a text from Daddy which read:

This girl is NOT sick.”

I replied: “Why do you say that?”

He writes back:

SHE TOLD ME SHE JUST NEEDED A BREAK!

You, my dear, are a genius!

&&

To add insult to injury, the Internet Search History reveals a Google search for

HOW NOT TO GO TO SCHOOL.

I wonder WHO looked that up!?

Well played, Gretel. Well played.

But, allow me to share a lesson of wisdom with you…

Fool me ONCE, shame on you.

Fool me TWICE, shame on me.

You WILL be to school with the sniffles and the coughies…

View original post 22 more words

India to get 200 low-cost airports by 2020

IndianEagle.com

India aviation news, India airline news, India aviation 2014 airshow, 200 lowcost airports in India

With 200 low-cost airports on the agenda of the Government, Indian aviation is all set to rise meteorically. Recently, the Ministry of Civil Aviation, India, declared the plan to build 200 low-cost airports in tier II and III cities across the country in the next 20 years, in order to expand the air travel network and improve air connectivity countrywide. Ashok Kumar, Joint Secretary, Ministry of Civil Aviation, addressed the media on the first day of India Aviation 2014 in Hyderabad.

Operations costs and service fees at the metro airports are immensely high, which the people of smaller towns cannot afford. It pushed the Civil Aviation Ministry to take the initiative to set up no-frill airports with basic infrastructure like that of major railway stations. Air traffic of the non-metro airports in India is expected to rise from 30% to 45% in the coming few years. The Airport Authority…

View original post 188 more words

Let me tell you

devilsadvocate23

Let me tell you a little bit about you. You have insecurities. You have fears. You have things that scare the shit out of you. That’s ok. So do I. Now all you need is to find your voice. Because here’s what I don’t have.. the empathy to hold your hand all the way, the patience to ask if you’re okay over and over, the ability to withstand your passive-aggressive behavior.. I choose not to. So do not project your issues onto me. They aren’t mine, I have my own. If you have a problem, convey that. If you don’t understand, ask your questions. If you don’t want something, don’t take it. Its simple. Do not force your problems onto me. I don’t know of your problems, I did not hear your questions and I did not see any refusal.. because you are mute. Your voice makes no sound. You…

View original post 67 more words

Class XI biology paper