Genetic Code, Translation, gene expression regulation, HGP by Nidhi gupta on Scribd

genetic code, translation,regulation of gene expression, Human genome Project

Genetics- Experiments proving DNA as genetic material by Nidhi gupta on Scribd

Molecular Basis of Inheritance- DNA structure and packaging by Nidhi gupta on Scribd

Holiday homework assignment

DAV Public School, Kailash Hills

Holiday Homework (2017-18)

                                                               Class XII (Biology)

HOTS

 1. If a branch “dasheri mango” is grafted on a tree producing “desi mangoes” what type

  of mangoes will be borne on grafted branch& other branches of the plant?                             1

       

2. Most sugarcane varieties cultivated today are aneuploids and are sterile. But they grow

  and perform extremely well. Sterility in sugarcane is not of any disadvantage. Why?            1

3. Why do organisms like algae and fungi which normally adopt asexual reproduction

   switch over to sexual method of reproduction just before the onset of adverse conditions?   1

4. If a certain plant when introduced into a new environment neither produces seeds nor it

  responds to vegetative propagation. How can more plants be produced?                                2

5. Even though each pollen grain has two male gametes. Why are at least 10 pollen grains and         

   not 5 pollen grains required to fertilise 10 ovules present in a particular carpel?                   2

6. “Apomictic genes are trying to be inserted in hybrid varieties” –Explain                         3

7. a) “Dehydration of seed increases their shelf life” – Explain                                            2

   b) Cleistogamous flowers are strictly self pollinating,” Explain. What is the disadvantage                 

      of this phenomenon?                                                                                                        2

   c) Even after killing the generative cell with a laser beam, the pollen grain of a flowering           

        plant germinates and produces normal pollen tube. How does it happen?                    1

8. Suppose the acrosome of mammalian spermatozoa does not function normally, how would              

   it affect fertilization? Give reasons.                                                                                    2                                                     

9. Fill the blank spaces a, b, c, and d given in the following table.

               S. No.        Organism                   Organ                    Gamete

                 (i)                 a                            Testes                 Spermatozoa                            2

                 (ii)         Human female                 b                         Ovum

                 (iii)      Plant (Angiosperm)           c                     Pollen grains

                 (iv)      Plant (pteridophytes)    antheridium                d

10. a) In which part of human female reproductive system do the following events take place?    1x5

   i. Release of 1st polar body

  ii. Release of 2nd polar body

  iii. Fertilization

  iv. Implantation

  b) From where do the signals for parturition originate and what does maternal pituitary release

  for simulating uterine contraction for child birth?

11. A woman who was pregnant (8 weeks), on clinical examination was found to have conceived

     a defective foetus with a serious genetic defect.

   1) With what test would the doctor have confirmed the genetic defect.

   2) What suggestive measure would you recommend?                                                                            2

12. Study the following diagram and answer the following questions:

                                   

                           

a) Label the parts A,B,C,D,E and F                                                                                                             3

b) How does D differ from F?                                                                                                                     1

            

13. State which law of Mendelian inheritance is expressed in the following

      diagram?

                      To different gamete        To different gamete                         1

14. Assume that no new mutations have arisen in the family.                                                   2

   Answer each question with either ‘Yes’ or ‘No’

i) Could this be inherited as recessive trait?

ii) Could this be inherited as dominant trait?

15. The map distance between A & B genes is 18 unit; between B & C is 20                         2

   unit and C & A is 2 unit.(a)What is the order of genes on a linkage group?(b)                               

   Write the unit of map distance.

16 . Colour blindness is a recessive trait. A couple with normal vision has two sons,             2

    one colour blind and one with normal vision. If the couple also has daughters what

    proportion of them will have normal vision?

18. From the given monohybrid ratio identify the type of inheritance and give one               3

     example each.

      i) Both phenotypic and genotypic ratio is 1:2:1

      ii) Phenotypic ratio is 3:1 and genotypic ratio is 1:2:1

17. Mention the steps involved in the following Pea plant cross                                               3

    

     Removal of anthers---------------------- A

              

   Transfer of Pollen------------------------ B

 

   Raising the next generation-------------C

19. Mention whether the male individuals of the following organisms are homozygous/  

    heterozygous.                                                                                                                   1x5

   i) Human = XY-XX

   ii) Hen = ZW-ZZ

   iii) Drosophila = XY-XX

   iv) Grasshopper = XO-XX

   v) Birds = ZZ-ZW

20. Mention the type of error in the following diseases:

   1. Sickle cell anaemia

   2. Haemophilia

   3. Phenylketonuria

   4. Down’s syndrome

   5. Klinefelter’s syndrome

Chapter 2: Reproduction in plants- Gametogenesis ( Male & Female)

Microsporogenesis and pollen grain formation

                                        

Megasporogenesis and embryo sac formation

Winter break homework

• Prepare a time schedule and revise well for your board exams.
• Break your syllabus and prepare chapters unit wise (referring to previous year questions).
•  Prepare the sample viva questions .
• Must submit properly covered practical files with completed index after winter break 

Happy new year and Best wishes for your bright future...
Work hard to achieve all your dreams.. Give your best and you will get the best....

DAV Public School, Kailash Hills

XII Practicals( 2016-17)

Sample Viva questions

1.       How many pairs of salivary glands are found in human beings?

2.       What are enzymes? Give two most important characteristics of enzymes.

3.       Why are enzymes referred to as biocatalyst?

4.       Why is NaCl added in the starch solution while testing salivary amylase activity?

5.       What are the end products of salivary amylase activity?

6.       What is achromic point?

7.       Did all three sets of tubes reach achromic point (while studying effect of pH and temperature)? If not , why so?

8.       What do you mean by optimum temperature, pH, and denaturation of enzyme?

9.       Why do we add NaCl while extracting DNA?

10.   Why is liquid soap added to the solution for extracting DNA out of cells?

11.   Why is chilled ethanol added while separating DNA fibres from the solution?

12.   Name the various types of soil.

13.   On what basis are various types of soils classified?

14.   Which component of soil is responsible for retention of water?

15.   Why is soil water important?

16.   Name the soil which can retain maximum and minimum amount of water.

17.   Which type of soil is ideal for plant growth?

18.   How is the study of soil structure important for selecting crops to be grown?

19.   How is pH of soil important and how is humus important for soil?

20.   Why is mitosis termed as equational division and meiosis as reductional division?

21.   What do you mean by term karyokinesis and cytokinesis?

22.   At what stage of cell division does nuclear membrane reappear?

23.   In which stage of cell division chromosomes are seen best?

24.   What are the main events occurring during different phases of mitosis and meiosis?

25.   What are the advantages of working with pea plant in dihybrid and monohybrid cross?

26.   What is the Law of Dominance, Law of segregation and Law of Independent Assortment?

27.   What are pedigree charts and how are they useful in genetical studies?

28.   What is colour blindness? Mention its genetical basis.

29.   What is haemophilia? Mention its genetical basis

30.   What is parasite? What do you understand by primary and secondary host?

31.   What causes Amoebic dysentery, malaria, Ascariasis?  Mention the symptoms and mode of infection?

32.   Name the ecological problems faced in dry xerophytic conditions.

33.   Name a few adaptations found in xerophytic plants to prevent loss of water.

34.   Name a few adaptations to manage minimum loss of water in desert animals..

35.   Name ecological problems in aquatic mode of life.

36.   Name ecological adaptations in aquatic mode of life.

37.   What is full form of BOD? What is DO and COD?

38.   What is significance of BOD in an aquatic ecosystem?

39.   What is the relationship between DO and BOD?