Previous Year Paper year:2009 : ICSE-X-Biology

Home Learn Fast select Course

Change Unit Change Subject Last Menu

ICSE-X-Biology

Previous Year Paper year:2009

with Solutions - page 3

#1-e-iii
Applying sudden brakes when a dog crosses your path.
Ans : Conditioned Reflex

#1-e-iv
Blinking of the eyelids on exposure to light.
Ans : Simple Reflex

#1-e-v
Tying one.s shoe lace.
Ans : Conditioned Reflex.

#1-f [5]
The diagram given below is that of a developing human foetus in the womb. Study the
same and then answer the questions which follow:

#1-f-i
Name the part labelled 1.
Ans : Umbilical cord.

#1-f-ii
Mention any two functions of the part labelled 2.
Ans : Part labelled 2 is placenta. Its two functions are as follows :
1. Provides diffusion for respiratory gases between mother and foetus.
2. Removes urea produced by foetus.

#1-f-iii
Explain the role played by the part labelled 3.
Ans : Part labelled 3 is amniotic fluid. Its function is that it acts as a shock absorber and protects the developing embryo from mechanical injuries.

#1-f-iv
What is the normal gestation period (in days) of the developing foetus?
Ans : 280 days.

#1-g [5]
Explain the following terms:

#1-g-i
Natality
Ans : Natality: The number of children bom per person in the population per unit time is termed as birth rate or natality.

#1-g-ii
Photolysis in photosynthesis
Ans : Photolysis in Photosynthesis: The splitting of water molecules into its two component ions in the'presence of light energy is called photolysis of water.

#1-g-iii
Antibiotic
Ans : Antibiotics: These are the chemical substances derived from microbes (like bacteria, yeast, moulds) which kill or prevent the growth of other microbes or pathogens. For eg. Penicillin is an antibiotic.

#1-g-iv
Root pressure
Ans : Root Pressure: Root pressure is the pressure generated by the cortical cells of the root, which pushes the water and minerals into the xylem of the root for the upward conduction.

#1-g-v
Parturition
Ans : Parturition: The delivery of the foetus or the child, birth is technically called as parturition.

#1-h [5]
Given below are five statements or questions followed by four choices. Select and
rewrite the correct answer to the given statements from the four choices given
below each statement: