RAWALPINDI BOARD 2012
BIOLOGY
PART-II
Time: 20 Min.
(Objective Part)
Marks: I7
Note: Four answer arc given against each question in columns A,B,C and D Select the right answer and on the separate. Answer Sheet, fill the circle A,B,C or D with pen or marker in front of that question number.

• The stage that lasts for days, weaks or even years is:

(a) leptotene
(b) zygotene
(c) pachytene
(d) diplotene

• Secretors have dominant  secretor gene "Sc" on chromosome:

(a) 18
(b) 19
(c) 20
(d) 21

• Meristem is:

(a) virus free
(b) bacteria free
(c) fungi free
(d) pathogen free

• Eustachian, tubes connect throat with:

(a) eyes
(b) middle ear
(c) nose
(d) tongue

• Over grazing may lead to:

(a) Tundra
(b) Taiga
(c) Grassland
(d) Desert

• Layering is a characteristic of:

(a) Tundra
(b) Grassland
(c) Taiga
(d) Desert

• The upper layer of earth crust is:

(a) rock
(b) sand
(c) soil
(d) clay

• Which one or the following is excretophore?

(a) stem
(b) root
(c) bark
(d) leaves

• The arginine is split by arginase to form urea and the precursor:

(a) ornithine
(b) citruline
(c) Alanine
(d) glycinc

• The living cells of cartilage are called:

(a) osteoblast
(b) osteocyte
(c) chondrocyte
(d) ostcoclast

• The collenchyma cells have protoplast and usually lack:

(a) secondary wall
(b) primary wall
(c) cell membrane
(d) vacuole

• Abscisic acid can be sprayed on tree crops to regulate:

(a) leaf drop
(b) shoot drop
(e) cone drop
(d) fruit drop

• Gastrin stimulates the secretion of:

(a) saliva
(b) intestinal juice
(c) gastric juice
(d) pancreatic juice

• Lutenizing harmone induces:

(a) flowering
(b) ovulation
(c) vernalization
(d) menopause

• Plant hormone florigen is produced in:

(a) flower
(b) root
(c) stem
(d) leaves

• Temperature influences rate of growth within a range from:

(a) 5-10°C
(b) 25-30°C
(c) 0-35°C
(d) 35-40°C

• The gene causing the white eye trait in drosophila resides only on the:

(a) Autosome 3
(b) Autosome 7
(c) y-chromosome
(d) x-chromosome

Time: 2:40 Hours
(Subjective Part)
Marks: 68
SECTION-I

2. Write short answer any Eight Parts. 16

• Define homeostasis and anhydrobiosis.
  
• Differentiate between metanephridium and protonephridium.
  
• Define counter-current multiplier.
  
• Give the cause of cramp.
  
• Give three disadvantages of exoshelaton.
  
• Define nastic movement. Name its types.
  
• What arc neurotransmitters? Give its examples.
  
• Give three main actions of nicotine on coordination.
  
• What is kinesis? Give an example.
  
• Differentiate between oogenesis and spermatogeesis.
  
• Define oestrous cycle.
  
• Define apomixes.

3. Write short answer any Eight Parts. 16

• Define genie system and give its one example.
  
• What is monochromy?
  
• What is meant by discontinuous variations?
  
• Define hydrothermal vents.
  
• Define modern synthesis.
  
• Name the species declared extinct in Pakistan.
  
• Differentiate between autecology and synecology.
  
• Define food chain with an example.
  
• Enlist two roles played by soil.
  
• Differentiate between primary and secondary succession. (xi) Define hydroelectric power.
  
• Define geo-thermal energy.

4. Write short answer any Six Parts. 12

• What is morula?
  
• How does mesoderm form coelom in developing embryo? (iii) What is karyotype?
  
• Differentiate between heterochromatin and euchromatin. (v) What i sphosphodiester bond?
  
• How does cytokinesis occur in plants?
  
• What are restriction endonuclease?
  
• What is climate?
  
• Give various features of profundal zone.

SECTION-II 

Answer any three questions from the following.

5. (a) Describe excretion in plants in detail. 04
(b) Elaborate chromosomal theory of heredity. 04

6. (a) Explain about significance of secondary growth in plants. 04
(b) What are reasons to use Drosophila as an experimental organism. 04

7. (a) Explain the mechanism of transmission of impulse through a synapse. 04
(b) Discus fossil record in favour of evolution. 04

8. (a) Describe human female reproductive cycle. 04
(b) Discuss flow of energy in an ecosystem. 04

9. (a) How does metaphase differ from anaphase of mitosis. 04
(b) Write a note green house effect. 04